JRC MARS Bulletin : crop monitoring in Europe. Vol. 29 No 5, May 2021.
Date: 2021-07-26
Institutions: Joint Research Centre
Subjects: agricultural situation, atmospheric conditions, crop production, crop yield, meteorology, serial publication

Issued: 25  May 2021 

JRC MARS Bulletin Vol. 29 No  5 

JRC MARS Bulletin 
Crop monitoring in Europe 
May 2021 

Cautiously positive yield outlook for winter crops 

At EU level, the yield forecasts for winter crops have been 

revised  slightly  upwards,  mainly  because  the  improved 

outlook  for  France,  Romania,  Bulgaria,  Hungary  and 

several  other  southern-central  European  countries 

outweighed  the  slight  downward  revisions  for  several 

more northerly countries, as well as for Greece. 

During  the  period  of  review,  large  parts  of  Europe  were 

affected  by  severe  cold  spells.  The  most  distinct  events 

that  occurred  after  the  reporting  period  of  the  April 

Bulletin (20 April) mostly affected north-western, central, 

eastern and northern Europe. The main impact of the cold 

events  on  winter  crops  has  been  a  delay  in  growth  and 

phenological  development,  and  some  reversible  damage 

to flowering  rapeseed stands, with no  major impacts on 

yield potential. In the case of spring cereals and summer 

crops, emergence and canopy development are delayed in 

the regions affected.  

Rain deficits that occurred in several EU regions had little 

or  no  negative  impact  on  yield  potential,  as,  in  most 

regions, soil water contents remained at adequate levels 

and  evaporative  demand  was  relatively 

low.  Rain 

surpluses in other parts of Europe mostly benefited crops 

by restoring soil water levels. 

Contents: 

1.
2.
3.
4.
5.
6.
7.

Agrometeorological overview
Remote sensing – observed canopy conditions
Pastures in Europe – regional monitoring
Sowing conditions
Country analysis
Crop yield forecasts
Atlas

Covers the period from 1 April until 15 May

JRC MARS Bulletin Vol. 29 No 5 –  25 May 2021 

1.  Agrometeorological overview 

1.1.  Areas of concern 

cereals  and  summer  crops,  emergence  and  canopy 

development  are  delayed  in  the  regions  affected.  Such 

delays imply an increased risk of the crops being exposed 

to possible heatwaves during sensitive stages in summer, 

but  fair  to  good  yields  are  still  possible  if  adequate 

conditions prevail during the remainder of the season.  

A  positive  aspect  of  the  colder-than-usual  conditions,  is 

that crop-water demand has also been lower than usual. 

As a consequence, the impacts on crops of rain deficits in 

these  regions,  as  shown  on  the  map,  were  very  limited; 

this  is  also  the  case  for  Italy,  southern  France,  and 

Romania,  where  temperatures  were  slightly  below 

average.  In some areas, spring sowing was delayed due 

to dry top  soils, thus adding  to the delay  caused by the 

cold weather.  

Recent lack of rainfall in Greece and Cyprus raises some 

concern. In Turkey, the pronounced rain deficit has led to 

increased use of irrigation to sustain winter crops. There 

are concerns for the summer crop season throughout the 

country, due to the low levels of irrigation reservoirs. Dry 

and  warm  conditions  in  the  Maghreb  region  further 

deteriorated the yield outlook for  cereal crops in  Algeria 

but had no negative impact on the end of the very positive 

growing season in Morocco. 

Intense rainfall in Poland, at the beginning of May, caused 

some  damage  to  crops,  and  some  sugar  beet  stands 

required re-sowing. In eastern France, rainy weather at the 

beginning of May is expected to have had some negative 

impact on flowering winter barley and durum wheat. The 

rain surplus observed in Czechia, northern Italy, Lithuania, 

the  Iberian  Peninsula,  Lithuania,  western  Russia  and 

eastern  Ukraine  benefited  crops  by  restoring  soil  water 

levels.  

Large parts of Europe were affected by severe cold spells 

during the period of review. The map above only reflects 

the  most  distinct  events  (in  terms  of  duration  and/or 

severity)  that  occurred  after  the  reporting  period  of  the 

April  Bulletin  (20  April),  which  mostly  affected  north-

western, 

central,  eastern  and  northern  Europe. 

Temperature anomalies reached -8°C (compared with the 

long-term average, LTA) in several parts of Germany and 

Denmark  during  this  period.  However,  in  most  cropland 

regions, minimum temperatures did not drop below -5°C 

in the last dekad of April, nor below -3°C in the first dekad 

of May. 

Similar to what was reported in the April Bulletin, the main 

impact of the cold events on winter crops has been a delay 

in  growth  and  phenological  development,  and  some 

reversible damage to flowering rapeseed stands, with no 

major  impacts  on  yield  potential.  In  the  case  of  spring 

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1.2.  Meteorological review (1 April until 15 May 2021) 

Colder-than-usual conditions were observed in a wide 
north-west/south-east  belt  extending  from  the  United 

Kingdom  to  Romania,  with  daily  mean  temperature 

anomalies  (with  respect  to  the  LTA)  from  -4°C  to  -2°C. 
Slightly  colder-than-usual  conditions  (with  daily 
mean  temperature  anomalies  ranging  from  -2°C  to  -

areas  of  France,  central  Mediterranean  and  Scotland 
record-breaking minimum temperatures (among the 
first three) were reached. 
Slightly warmer- and warmer-than-usual conditions 
were observed in Turkey and European Russia. Daily mean 

temperature  anomalies  were  less  than  2°C  in  most  of 

0.5°C) were recorded in the rest of Europe, except for the 

Turkey, except for its eastern part where higher values (up 

Iberian Peninsula, Finland, Greece and European Russia. In 

to  4°C)  were  recorded.  The  same  holds  for  European 

most of the above-mentioned areas, an exceptionally high 

Russia, which presents an eastward gradient of increasing 

number (above 100% of the LTA) of cold days (i.e. days 

with daily minimum temperature less or equal to 0°C) was 

observed.  

These  unusual  weather  conditions  were  caused  by  a 
sequence  of  three  severe  cold  spells  that  hit  Europe, 
respectively, at the beginning, mid and at the end of April. 

The  first  cold  spell  mostly  affected  central  and  south-

eastern  Europe;  the  second  one  hit  western,  central  and 

south-eastern Europe. While the third one mostly affected 

central, eastern and northern Europe. As a consequence, in 
large parts of central Europe April 2021 was among the 
three coldest (by looking at our historical archive, since 
1979) in terms of mean daily temperature. While, in many 

anomalies, up to 6°C.  
Wetter-than-usual conditions were observed in large 
areas  of  central-eastern  Europe,  south-eastern  France, 

Sweden, Finland and European Russia. Anomalies of total 

precipitation  were  mainly  from  50%  to  80%,  although 

higher values (up to 150%) were recorded in a meridional 

belt extending over European Russia.  
Drier-than-usual  conditions  were  mainly  observed  in 
large regions of eastern Italy, south-eastern Europe and 

Turkey.  While  in  most  of  these  areas  the  anomalies  of 

total  precipitation  were  mostly  from  -50%  to  -30%,  in 

large areas of Turkey and Greece values reaching -80% 

(and also -100%) were observed.  

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New Long-Term-Average (LTA) 

All Long-Term-Averages (LTAs) used to define anomalies in 

the  analyses  have  been  updated.  Following 

the 

recommendation of the World Meteorological Organization, 

considering the higher availability and quality of stations in 

the  last  decades,  and  to  have  LTA  values  closer  to  what 

people  perceive  as  being  “normal”  conditions,  the  new 

reference period is 1991-2020. As shown in the map below, 

differences are not too pronounced and  mostly  point to  a 

new warmer LTA. 

Differences between the new and the previous annual mean 

temperature LTA.  

Although this change does not modify trend and ranking, it 
affects the anomalies used and described in the Bulletins.  
As an example of such differences, the maps on the right 
show  the  anomalies  of  2020  annual  mean  temperature 
derived by using the previous LTA and the new 1991-2020 
LTA. 

2020  annual  mean  temperature  anomalies  w.r.t.  the 

previous (upper panel) and the new (lower panel) LTA.  

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1.3.  Weather forecast (22-28 May) 

Weather  conditions  will  be  mainly  determined  by  a  trough  evolving  over  the  North  Sea,  a  cyclonic  system  over  the 

eastern Mediterranean, and small scale disturbances affecting the western Euro-Mediterranean region. This atmospheric 

pattern will trigger atmospheric instabilities, rainfall and colder flow in the affected regions. 

Colder-than-usual  conditions  are forecast in most of 
north-western, central, eastern, and northern Europe with 

between  10  mm  and  40  mm;  locally  up  to  80  mm)  are 

expected  in  most  of  Europe,  except  in  south-eastern 

daily  mean  temperature  anomalies  (with  respect  to  the 

LTA) mainly from -6 °C to -2 °C.  
Warmer-than-usual conditions are expected in south-
eastern  Europe,  southern  Italy,  Turkey,  eastern  Ukraine, 

regions,  large  areas  of  the  Iberian  Peninsula,  Italy,  and 
Turkey, where dry conditions are forecast.  
Long-range  weather  forecast  for  June,  July,  August 
points to likely to occur warmer-than-usual conditions in 

and European Russia. Daily mean temperature anomalies 

the  Euro-Mediterranean  region  (extremely  likely  over 

in  these  regions  will  mainly  range  from  2  °C  to  6  °C. 
Slightly warmer-than-usual conditions are forecast in 
large parts of Spain and Ukraine.   
Wet  conditions  (with  accumulated  precipitation  mainly 

Turkey).  Likely  to  occur  drier-than-usual  conditions  are 

forecast in large parts of eastern Europe, Turkey, and the 

central Mediterranean region. 

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2.  Remote sensing – observed canopy conditions 

Fresh spring temperatures slowed biomass accumulation 

The map displays the differences between the Normalized Difference Vegetation Index (NDVI) cumulated from 1 April 

to 10 May 2021 and the medium-term average (MTA, 2011-2020) for the same period. Positive anomalies (in green) 

reflect above-average canopy density and/or early crop development, while negative anomalies (in red) reflect below-

average biomass accumulation and/or late crop development. 

The  map  above  displays  predominately  winter  crop 

conditions,  as  the  summer  crop  season  has  just  started 

Italy,  colder-than-usual  weather  slowed  down  crop 
development. Crop conditions are fair to slightly weak and 

and contributes little to NDVI values. Average to slightly 

winter  cereals  have  reached  flowering  with  around  10 

delayed  crop  stages  are  predominantly  observed  in 

days of delay with respect to the average, (e.g. Basilicata). 

southern and western regions, with the exception of the 

In  northern  regions,  favourable  biomass  accumulation 

Iberian  Peninsula,  where  early  and  favourable  crop 

development still prevails. Cold spring temperatures have 

further  increased  the  negative  anomalies  in  central 

Europe. Conversely, a favourable biomass accumulation is 

observed in Romania and southern Ukraine, thanks to the 

overall  mild 

spring 

temperatures  and  sufficient 

precipitation.  
Spain shows a slowdown in crop development due to cold 
temperatures,  slightly  lower  than  the  average.  Crops  in 

was  sustained  by  abundant  precipitation  that  occurred 
from the second half of April onwards. In France, despite 
the dry conditions observed in April, biomass accumulation 
is  proceeding  in  line  with  the  average  (e.g.  Centre).  The 
impact of the dry conditions on biomass accumulation was 

mitigated  by  cold  temperatures  that  reduced  water 
demand  and  evaporation.  In  northern  Germany  and 
Poland,  the  low  temperatures  registered  in  April  have 
caused  a  slight  slowdown  in  crop  growth,  but  crop 

southern regions are in early flowering, while in northern 

development  as  observed  by  the  NDVI  remains  slightly 

regions  green  biomass  accumulation  is  still  ongoing, 
supported by the rainfall that arrived in April. In southern 

anticipated and biomass accumulation is still sustained by 

the  well-distributed  precipitation  in  early  spring  (e.g. 

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Sachsen-Anhalt, Lódzkie). The map displays a large area 
with  negative  anomalies  (red  colours)  covering  central 
Europe 
(including  Slovakia,  the  Czech  Republic, 
Austria, Hungary and southern regions of Germany and 
Poland).  In  these  regions,  a  crop  development  delay  of 

more  than  10  days  is  registered  with  respect  to  the 
average (e.g. Niederösterreich). This signifies an increased 

risk of heat stress later in the season, as yield formation 

stages might now coincide with the hotter periods during 
summer.  In  the  Baltic  countries,  the  positive  anomaly 
highlighted on the map reflects a strong advancement of 
the season due to mild spring temperatures. In Romania 
and Bulgaria, crops continue to benefit from favourable 
weather  conditions  characterised  by  slightly  below 

average  temperatures  and  persistent  rainfall.  These 

almost no impact on crops in Romania (e.g. Macroregiunea 
Patru). In Greece, crop biomass accumulation is average 
to  fair  while  crop  development,  already  delayed  since 

early  spring,  was  further  hampered  by  a  cold  spell 

recorded in April (e.g. Central Macedonia). Mixed conditions 
are  observed  in  Ukraine.  Southern  regions,  with  a 
prevalence of winter crops, are experiencing a positive and 

advanced  start  of  the  season,  while  eastern  regions 
(including  European  Russia),  are  characterised  by  a 
delayed  season.  However,  in  these  regions,  good  crop 

biomass  accumulation  is  expected  thanks  to  abundant 

precipitation and temperatures close or just slightly higher 
than the average (e.g. Rostovskaya Oblast). In the United 
Kingdom, conditions similar to those described for France 
occurred. The biomass accumulation shows values in line 

regions also faced a drop in temperatures in April, which 

with or slightly below the average, but more rain is needed 

slowed  down  crop  development in  Bulgaria,  while it had 

to restore soil moisture and sustain crop growth. 

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3.  Pastures in Europe – regional monitoring 

Cold weather conditions limited pasture productivity 

Observations are mixed, as canopy conditions have been under cold stress in the northern, central and eastern regions, 
but also under water stress in several places. The return of rain has alleviated the water stress, but the cold has had a 
delaying effect on biomass growth. 

Austria,  Germany,  Poland,  Czechia,  Slovakia, 
Slovenia, Croatia, Hungary, Bulgaria, Romania, Italy, 
the  Benelux  countries,  Ireland,  Finland,  Denmark, 
Sweden and the Baltic countries had much colder-than-
usual  weather  conditions  throughout  April  and  the  first 

low. While a substantial rain deficit, 50% below the LTA, 

was  observed,  the  water  demand  was  relatively  low 

thanks to the cold temperatures, thus limiting the impact 

of  water  stress.  Substantial  rainfall  has  been  observed 

since  the  beginning  of  May.  The  pasture  productivity, 

week of May. This generated a slow growth of pastures. 

considering the meteorological conditions, is expected to 

Even  though  rainfall  in  several  of  these  regions  – 

be  below  average,  with  some  areas  impacted  locally  by 

especially in April –  was substantially less than usual (e.g. 

southern  Ireland,  Austria,  Hungary,  central  Romania), 

water  supply  was  mostly  adequate  because  of  the 

water stress. Similarly, the colder-than-usual conditions in 
southern  Italy  could  be  regarded  as  beneficial  to 
pastures, which were receiving less rainfall. Even though 

reduced  evaporative  demand.  Some  pasture  areas  in 
western Poland were negatively impacted by inundation 
due to intense rainfall events at the beginning of May.  
In  France  (as  well  as  in  south-western  parts  of  the 
Benelux), a substantial rain deficit was observed in April 
in all regions except Rhone-Alpes and PACA. Radiation was 

growth was reduced, no water stress is observed thanks 

to the reduced evapotranspiration demand. 
In a large part of southern Greece and the South Aegean 
islands, Crete in particular, pastures are under moderate 

stress  due  to  slightly  warmer-than-usual  temperatures, 

mostly at the end of April and the beginning of May, and 

well above the LTA but temperatures were exceptionally 

dry  spells  since  the  end  of  April.  In  northern  parts  of 

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JRC MARS Bulletin Vol. 29 No 5 –  25 May 2021 

Greece  (Northern  Aegean  islands,  Epirus  and  Eastern 

Macedonia)  pasture  productivity  is  either  in  line  with  or 

Spain  and  Portugal  experienced  well-distributed  close-
to-average precipitation since the beginning of April. 

slightly below the seasonal average. 

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4.  Sowing conditions 

Spring barley 
Cold weather delays emergence in most European countries 

Sowing  progressed  well  in  northern  and  eastern  Europe, 

conditions, but improved soil moisture conditions since the 

but  lower  than  usual  temperatures  delayed  germination 

end  of  April  ensured  good  progress,  and  higher 

and early growth in most of these countries. 

temperatures at the beginning of May favoured adequate 

In  most  European  countries 

(e.g.  France,  Benelux, 

Denmark,  Germany,  Poland,  Ireland,  UK),  sowing  was 

mainly  concluded  in  April.  Emergence  and  early  growth 

has  generally  been  slow  due  to  continued  cold  weather 

that, combined with dry conditions, resulted in uneven crop 

establishment  in  some  regions  (e.g.  southern  Ireland, 

south-eastern  United  Kingdom,  south-western  Benelux). 

However, weather conditions improved at the beginning of 

May and are likely to promote growth in the coming weeks. 

In  Hungary,  Czechia,  Slovakia  and  Croatia,  the  sowing 

campaign  started  with  a  delay  due  to  cold  and  dry 

Sugar beet and potatoes 
Slow start to the season 

germination  and  uniform  establishment.  In  Romania, 

where the sowing campaign progressed well in April, cold 

temperatures delayed germination and crop emergence. 

In  the  Baltic  countries  and  Sweden,  spring  sowings  are 

progressing well within the normal window, although the 

cold  weather  slowed  seed  germination.  In  southern 

Finland, the sowing of spring cereals started at the end of 

April despite the cold and rainy weather, whereas in the 

rest of the country sowing is expected to be in full swing 

in mid-May, which is a normal time for this country. 

Colder-than-usual  weather  conditions  slowed  down 

Notwithstanding  frequent  cold  snaps  in  many  regions, 

germination and early development of sugar beet across 

frost  damages  were  generally  minor,  with  the  notable 

western and central Europe. 

Despite some delays with the onset of sugar beet sowing 

due  to  low  temperatures  and  a  slower  pace  of  field 

operations at the  beginning  of April (as  described in the 

previous  bulletin),  the  sugar  beet  sowing  campaign  was 

finalised within a normal time window, i.e. by the end of 

April  in  Germany,  Poland  and  Benelux.  The  beginning  of 

the season was generally not favourable for sugar beet in 

the main producing regions of western and central Europe 

due  to  colder-than-usual  weather  conditions.  Below-

average daily temperatures and frost events delayed the 

emergence  and  early  development  of  seedlings. 

exception  of  France  where  approximately  10%  of  the 

sown  area  required  re-sowing  after  a  cold  spell  at  the 

beginning of April. The conditions for the re-sown plants 

were not favourable throughout April due to cold and dry 

topsoils,  but  improved  in  May.  Additionally,  in  Poland, 

damage  to  sugar  beet  stands  was  reported  due  to 

torrential rains at the beginning of May.  

Potatoes,  of  which  the  main  production  regions  coincide 

with those of sugar beet, faced similar challenges. Most 

plantings of the main crop started in the second half of 

April  and  were  finalised  mid-May,  but  emergence  and 

early development (if emergence already occurred) have 

been very slow.  

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Maize 
Cold weather delaying maize germination 

Favourable  weather  conditions  have  generally  been 

substantial  rainfall  occurred  during  the  usual  sowing 

observed to complete the maize sowing campaign, which 

window.  

is  currently  coming  to  an  end  in  the  main  producing 

While sowings are almost completed, weather conditions 

regions.  Nonetheless,  substantially  colder-than-usual 

have not been particularly beneficial for crop emergence 

temperatures  since  April  have  been  slowing  down  crop 

considering the colder-than-usual temperatures observed 

emergence. 

In  France,  the  sowing  campaign  completed  10  days  in 

advance compared to an average year, as the soil was dry 

and  allowed  farmers  to  proceed  quickly  with  the  field 

work. In Germany, the sowing campaign is completed and 

conditions  have  been  generally 

favourable.  No 

unfavourable  weather  conditions  have  been  hampering 

the  sowing  campaign  in  Italy,  Serbia,  Romania,  Greece, 

Bulgaria  where  the  sowing  is  completed,  while  it  is 

currently coming to an end in Austria and Hungary. Some 

delays  have  been  observed  in  Poland,  Czechia  and 

Slovakia  where,  in  addition  to  the  colder-than-usual 

temperatures  observed  since  the  beginning  of  April, 

in  all  the  previously  cited  countries.  April  2021  is  the 

coldest April recorded in large parts of Europe since 1979. 

Soil  temperatures  were  sub-optimal  to  ensure  quick 

germination. In France, adding to the cold temperatures, a 

substantial  rainfall  deficit  (<50%  than  the  LTA  in  April) 

further contributed to an unfavourable start to the season. 

Since the beginning of May, substantial rainfall has been 

observed, alleviating the concern of a possible prolonged 

water stress for grain maize while the season is only just 

starting.  

Only  Spain  was  not  exposed  to  the  colder-than-usual 

weather: Temperatures have been warmer than usual and 

rainfall  close  to  the  LTA  since  the  beginning  of  April, 

ensuring a good start to the season. 

Sunflowers 
Cold temperatures delay the sowing campaign 

The  sowing  of  sunflower  progressed  well  after  the  low 

to recover and ensure a good establishment. 

temperatures  of  April  that  delayed  the  beginning  of  the 

In France, the sowing campaign is slightly delayed and still 

campaign.  Emergence  has  been  generally  slow,  but  the 

ongoing, but the rainfall at the beginning of May created 

increasing temperatures  at  the end of the period should 

beneficial conditions for emergence. 

promote 

initial  growth  and  ensure  a  good  crop 

In  Spain  and  Portugal,  a  favourable  rainfall  distribution 

establishment. 

In  Hungary  and  Croatia,  the  sowing  campaign  started 

delayed due to cold and dry conditions, but improved soil 

moisture since the end of April has ensured good progress, 

an adequate germination and uniform establishment.  

In Romania and Bulgaria, the sowing campaign progressed 

well  in  April,  but  emergence  was  delayed  by  cold 

conditions.  Similar  delays  in  emergence  have  been 

reported in Slovakia, Czechia, Austria and Germany. 

In Greece, the sowing of sunflower progressed well after 

a  slight  delay  in  April.  Cold  conditions  slowed  down 

emergence, but the improved weather at the end of April 

with some rainfall and warmer temperatures helped crops 

resulted  in  good  conditions  for  sunflower  sowing,  which 

has now been mostly concluded. In these countries, after 

a slight  delay in emergence, crops are  currently in good 

condition. 

In Italy, while the first sowings were delayed, later in April 

soil  and  weather  conditions  have  been  favourable  for 

sunflower sowing and germination. 

In  Ukraine,  sowings  started  slightly  delayed  in  April,  but 

are  now  progressing  well,  being  about  halfway  through 

planting.  Temperatures  and  soil  moisture  since  the 

beginning  of  May  have  been  adequate  for  sowing 

completion and crop emergence. 

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5.  Country analysis 

5.1.  European Union 

France 
Unusually cold and dry weather had limited impacts on the main arable crops 

A rain deficit was observed in April, with limited impacts 

on  crops,  because  of  the  exceptionally  cold  weather 

observed  during  the  period  under  review  which  limited 

water demand. The rain has returned since the beginning 

of  May.  Winter  crop  conditions  are  generally  favourable, 

but  summer  crops  are  facing  a  very  slow  start  to  the 

season in the northern half. 

The  period  under  review  has  been  one  of  the  coldest 
recorded since 1979, with the exception of south-western 
regions.  A  rain  deficit  was  observed  in  April,  with 
cumulative  rainfall  50%  below  the  LTA  in  most  of  the 
country  (except  the  south-east);  it  was  particularly 
pronounced  in  Poitou-Charentes  and  Pays-de-la-Loire, 
where April rainfall was locally less than 20% of the LTA. 
Since the beginning of May, rainy weather has prevailed. 
While winter cereals were exposed to the cold spell in the 
beginning of April, the impacts on soft wheat are expected 
to be very limited. Winter barley and durum wheat yield 
potentials are expected to have been negatively affected 

due  to  some  frost  damage  on  the  ears,  and  the  rainy 
weather  during  the  flowering  period,  beginning  of  May. 
Rapeseed  was  also  impacted  by  the  cold  spell,  in  early 
April,  but  the  radiation  surplus  during  the  period  under 
review  was  favourable  to  flowering.  While  the  forecasts 
for  soft  wheat  and  rapeseed  yields  have  been  revised 
upward,  the  forecast  for  durum  wheat  has  been 
maintained  below  the  5-year  average  and  winter  barley 
revised downward.  
Sugar  beet  and  spring  barley  had  a  difficult  start, 
impacted by the frost and exposed to the rain deficit. The 
rainy  weather  observed  since  the  beginning  of  May  has 
been beneficial and improved the crop conditions. 
While  the  dry  weather  was  beneficial  for  the  sowing  of 
summer crops, the cold temperatures slowed emergence 
and early development, with the exception of the south-
western 
in  early 
regions.  The  delays  observed 
development are exposing the newly sown crops to birds, 
and insect pests. The yield forecast remains on trend as 
this is only the start of the season. 

15

 
 
 
 
 
JRC MARS Bulletin Vol. 29 No 5 –  25 May 2021 

Germany 
Good yield potential for winter cereals is kept

The 

unsteady  weather  with 

lower-than-average 

clear  rainfall  surplus  for  most  of  northern  and  eastern 

temperatures  and  sufficient  precipitation  amounts  –  as 

Germany and eastern Bayern. The previously identified dry 

described in the April Bulletin- continues for Germany and 

spots in Ober- and Niederbayern as well as in Schwaben 

results in a general slowdown of crop growth but overall 

received  sufficient  rainfall  to  further  sustain  crop  and 

good  conditions.  Forecasts  are  now  mostly  based  on 

pasture  growth.  Soil  moisture  conditions  are  good 

model  results  for  winter  cereals  and  rapeseed  and  are 

throughout  the  country  providing  some  buffer  for  the 

generally well above the 5-year average. 

weeks to come as more rain is forecast.  

April  as  a  whole  presents  itself  with  a  lower  than  usual 

Winter  cereals  are  at  heading  stage  with  the  model 

temperature regime. For some of the regions (e.g. Hessen), 

indicating a delay of around 10 days. Biomass gains have 

the average April temperatures are the lowest we have on 

slowed  down  now  considerably  in  Baden-Wuerttemberg 

record and the first half of May is clearly marked as colder 

and  Bayern,  whereas  we  see  steady  growth,  albeit 

than  average  too.  Numerous  frost  events  contributed  to 

delayed, in Niedersachsen and  Nordrhein-Westfalen. The 

these  low  average  temperatures.  The  last  night  frosts 

soft wheat yield forecast is slightly lower than last year 

occurred around 7 or 8 May and were followed by a steep 

and on the conservative side for the moment, but there is 

increase in temperatures, nearly reaching 30 degrees on 

certainly  room  for  a  higher  yield  to  materialize  in  the 

9  or  10  May.  These  are  stressful  conditions  for  crops, 

coming  week.  Winter  barley  is  already  set  clearly  above 

especially  for  the  flowering  rapeseed,  but  no  severe 

the yield of last year.  

damage  is  expected,  although  yield  potential  might  be 

Maize  and  potato  sowings  were  delayed  but  are 

diminished slightly.  

completed by now, sugar beet sowing is still ongoing. 

Rainfall cumulates during the period of review vary mostly 

Yield forecasts are either using our crop model results or 

between 50 and 100 mm with the higher amounts close 

are based on historical trends, the latter specifically when 

to the Nordic Sea and the Alps. These cumulates mean a 

it concerns summer crops. 

16

 
 
 
 
 
JRC MARS Bulletin Vol. 29 No 5 –  25 May 2021 

Poland 
Cold and wet conditions delayed crop development and hampered spring field 
operations 

Temperatures  in  April  and  the  beginning  of  May  were 

in April, the phenological development of winter and spring 

substantially  below  the  average,  which  slowed  the 

crops  became  noticeably  delayed  as  compared  to  an 

development  of  winter  and  spring  crops.  Cold  and  wet 

average year.  Nonetheless,  winter crops are  generally in 

conditions  delayed the sowing of maize and  spring-time 

good condition. Rapeseed generally did not suffer serious 

field  operations.  The  start  of  the  season  was  not 

damage  due  to  late  April  cold  spells,  as  flowering  was 

favourable for sugar beet due to the low temperatures and 

delayed  with  respect  to  previous  years  (and  is  about  to 

intense rains in May.  

Substantially 

colder-than-usual 

temperatures  were 

recorded  in  April  and  in  the  beginning  of  May.  Frequent 

frost events occurred, with temperature minima  below -

6°C  at  the  end  of  April.  Cumulative  precipitation  was 

considerably  above  the  average,  except  for  the  NW 

regions that remained drier than usual. The beginning of 

May  brought  intense  precipitation  events,  exceeding 

40mm/day  in  some  regions.  Cumulative  global  radiation 

was below average.  

As a consequence of the predominantly low temperatures 

begin).  Sowing  of  maize  started  late  (2-3  weeks  later 

compared to last year) due to the cold and wet conditions 

and is still ongoing in some regions. The sugar beet sowing 

campaign  was  finalised  at  the  end  of  April.  Low 

temperatures  delayed 

the  emergence  and  early 

development  of  seedlings,  but  no  serious  frost  damage 

was noted. However, some sugar beet stands required re-

sowing after the torrential May rains. Currently crops are 

mostly  forecast  around  average  historical 

trends. 

However, adequate thermal conditions are needed in the 

following  weeks  to  sustain  these  average  forecasts  for 

summer and spring crops. 

17

 
 
 
 
 
 
JRC MARS Bulletin Vol. 29 No 5 –  25 May 2021 

Ireland 
Positive yield outlook despite exceptionally cold conditions 

Cold weather slowed down crop development. The rainfall 

barley reached the flag leaf stage. Winter rapeseed is at 

at the beginning of May mitigated the soil moisture deficit 

flowering.  The  condition  of  crops  improved  after  the 

in the south. Winter crops are in good condition and with 

rainfall  at  the  beginning  of  May.  Simulated  leaf  area  is 

low disease pressure. The yield outlook remains positive 

close  to  the  LTA  for  winter  barley  and  rapeseed,  and 

for winter and spring crops. 

Cold temperatures prevailed during the period of review. 

Since  the  end  of  the  first  dekad  of  May,  temperatures 

returned  to  close  to  seasonal  values.  Rainfall  remained 

below average, but rain at the beginning of May improved 

topsoil  water  conditions  for  spring  crops.  Cumulative 

radiation was above average. 

Cold conditions slowed crop development. According to our 

models,  crop  development  of  winter  cereals  is  currently 

slightly delayed compared to an average season. Winter 

following the LTA with some delay for winter wheat and 

spring  barley.  The  dry  weather  of  April  allowed  the 

completion of spring sowing in mid-April but the continued 

cold  and  dry  weather  created  uneven  establishment  for 

later sown crops. However, winter and spring crops can still 

recover and the return of favourable weather conditions 

in  terms  of  warmer  temperatures  and  soil  moisture 

conditions is likely to boost growth in the coming weeks. 

Yield forecasts remain positive for winter and spring crops 

and above the 5-year average. 

18

 
 
 
 
 
 
 
JRC MARS Bulletin Vol. 29 No 5 –  25 May 2021 

Spain and Portugal 
Winter cereals and spring barley still at risk despite substantial rain 

Conditions  for  the  emergence  of  summer  crops  were 

water contents to above the near-critical levels mentioned 

favourable  as  well-distributed  rainfall  provided  optimal 

in  the  April  Bulletin.  Substantial  rainfall  in  the  coming 

soil moisture conditions. Rainfall was sufficient to sustain 

weeks  will  still  be  necessary  to  avoid  serious  water 

adequate  growth  and  development  of  winter  crops  and 

constraints which would lead to early senescence with a 

spring barley, but soil water contents remain very close to 

considerable yield penalty. 

critical  levels.  The  yield  outlook  remains  well  below  last 

Consequently,  the  yield  forecasts  for  winter  crops  and 

year’s level and close to the 5-year average. 

spring  barley  have  remained  unchanged  at  conservative 

During the period under review, rainfall was close to the 

LTA and evenly  distributed over numerous  small events. 

Temperatures are following the LTA with some variations, 

leading to some warmer days in the northern regions and 

some  colder  days  in  south-western  regions,  such  as 

Alentejo in Portugal.  

The favourable temperatures and well-distributed rainfall 

allowed the growth of  winter crops and spring barley to 

continue  at  average  or  above-average  levels,  while 

phenological  development  is  slightly  advanced  in  both 

Portugal and Spain. However, while rainfall was sufficient 

to avoid stress conditions, it was insufficient to raise soil 

levels:  somewhat  above  the  5-year  average  for  winter 

cereals  and  below  the  5-year  average  for  spring  barley; 

whereas the forecast for rapeseed remains close to the 5-

year average. 

Sunflower  had  a  delayed  start  of  emergence  alongside 

slightly  weaker  stem  development,  due  to  a  dry  period 

after  emergence,  but  with  actual  overall  favourable 

conditions.  Maize  experienced  favourable  conditions  for 

emergence.  

Water reservoirs in Spain are estimated at 61% of their 

full capacity (www.embalses.net), close to the 2019 lower 

levels and well below the 69% 10-year average. 

19

 
 
 
 
 
 
 
 
JRC MARS Bulletin Vol. 29 No 5 –  25 May 2021 

Italy 
Steady crop growth but delayed 

Winter cereals are notably delayed  but predominantly in 

Along  the  Tirrenic  coast  (Toscana,  Lazio,  Campania)  and 

favourable conditions. Crop yield forecasts increased and 

Sicilia  the  weather  was  slightly  wetter  and  colder  than 

now are above the 5-year average. Summer crop forecasts 

usual. 

are still based on the historical trend. 

While  on  one  side  a  cold  spring  delayed  winter  crop 

In northern Italy, a dry spell that started in late February 

development, 

on 

the 

other 

side 

it 

reduced 

ended  around  10  April,  but  since  then  well  distributed 

evapotranspiration  and  prevented  a  significant  soil 

precipitation occurred in most of the regions. The overall 

moisture 

depletion. 

In 

addition,  well-distributed 

accumulated rainfall remains below the average, notably 

precipitation maintained crops in good shape. In southern 

in  Piemonte  and  Emilia  Romagna  (-30%).  Vegetation 

regions (Puglia, Basilicata) winter crops are flowering with 

growth  slowed  down  due  to  a  cold  spell  in  April,  while 

average  to  slightly  below  the  average  crop  biomass 

temperatures in May so far have been average. 

accumulation. 

Along  the  Adriatic  coast  (Marche,  Abruzzo,  Molise  and 

Summer crop sowings were generally delayed due to the 

Puglia) April and May were drier than usual resulting in a 

cold and dry periods. The early sown  maize (mid to late 

precipitation deficit between 25mm and 50mm (-30% to 

March) emerged up to one month later and could present 

-50%). A significant temperature variability was observed 

locally  uneven  growth,  mostly  in  Piemonte  and  Veneto. 

in  the  first  half  of  April,  before  leaving  the  pace  to  a 

Some  delays  occurred  for  the  sowings  of  soybean, 

generally  colder-than-usual  period  (15  April  –  1  May).  A 

sunflower and sugar beet. 

similar weather pattern was observed in the inland regions 

. 

of eastern Toscana, Umbria and Basilicata.  

20

 
 
 
 
 
 
 
JRC MARS Bulletin Vol. 29 No 5 –  25 May 2021 

Hungary 
Delayed crop development 

The development of winter crops was delayed due to cold 

temperatures  in  the  first  half  of  spring.  Several  rainfall 

events during this reporting period prevented water stress, 

the MTA. The negative impact of the dry  conditions was 
reduced thanks to this delay. Despite cold temperatures, 
no frost-kill events occurred after mid-April. We maintain 

but the still suboptimal soil moisture levels are concerning. 

forecasts close to the trends for winter cereals, as rain in 

Special  attention  will  have  to  be  paid  to  end-of-May 

May  plays  a  major  role  in  supporting  heading/flowering. 

rainfall. 

Average temperatures of the reporting period were among 

the lowest of our entire record.  April temperatures were 

the lowest recorded for the last 20 years. In the beginning 

of April, dry conditions were a source of concern for winter 

crop development. The cumulative precipitation since April 

(40  to  100  mm)  was  sufficient  to  recover  a  favourable 

topsoil layer water content. 

The  low  temperatures  of  the  past  weeks,  leading  to  a 

limited growing degree days accumulation, slowed down 

the  plant  development  of  winter  crops.  The  analysis  of 

satellite imagery confirmed a 1-week delay compared to 

For  rapeseed,  the  impacts  of  the  frost  event  in  the 

beginning of April are not yet established. To maintain a 

normal  yield  level,  favourable  weather  (warm  and  wet) 

would  be  needed  at  the  end  of  spring.  Following  this 

uncertainty,  the  yield  forecast  for  rapeseed  was  revised 

downward. 

Due to the cold and dry conditions in early April, the sowing 

of summer and spring crops has been slightly delayed. As 

of mid-May, the sowing campaign is mostly over since the 

conditions at the end of  April were favourable. The crop 

weather has been also favourable for good emergence. 

21

 
 
 
 
 
 
 
 
 
JRC MARS Bulletin Vol. 29 No 5 –  25 May 2021 

Romania 
Good crop yield outlook for winter cereals 

April  has  been  among  the  three  coldest  months  on  our 

remains  at  an  adequate  level  for  winter  cereals  and 

records  in  Romania,  slowing  down  the  phenological 

spring-sown  crops.  The  cold  weather  anomaly  slowed 

development  of  winter  crops.  Large  parts  of  the  country 

down the phenological development of winter crops, which 

recorded  a  rainfall  deficit;  however,  the  soil  moisture 

was  advanced  due  to  the  mild  winter  and  early  spring. 

remains at satisfactory levels. The crop yield outlook has 

Winter  soft  wheat  is  currently  in  heading  stage.  The 

been revised upwards for winter cereals.  

sowing  of  spring  crops  was  mainly  finished  in  April; 

After a substantially colder-than-usual April with average 

air temperatures between 2°C and 4°C below the LTA, the 

beginning of May was characterised by warmer weather 

conditions.  Rainfall  cumulates  were  mainly  between 

10%and 50% below the LTA, except in Nord-Vest region 

where  abundant  rainfall  (>100  mm)  was  recorded 

exceeding  the  LTA  by  more  than  50%.  Even  though  the 

rainfall  deficit  prevailed  during  the  period  of  review  in 

major  parts  of  the  country,  the  soil  moisture  generally 

however, emergence was delayed by cold conditions.  

Even  though  colder  weather  slowed  the  phenological 

development, winter cereals are progressing well. The crop 

yield  potential  of  soft  wheat  will  be  defined  in  the 

following weeks when the flowering stage will occur. Due 

to overall favourable conditions, we have revised our crop 

yield  outlook  for  winter  cereals  upwards.  The  crop  yield 

outlook  for  spring  crops  currently  remains  at  the  long-

term average.  

22

 
 
 
 
 
 
 
 
 
JRC MARS Bulletin Vol. 29 No 5 –  25 May 2021 

Bulgaria 
Positive crop yield outlook for winter cereals 

A  cold  start  to  April  was  followed  by  warmer  conditions 

period was characterised by drier conditions, especially in 

during  the  last  dekad  of  April  and  first  half  of  May.  The 

southern Bulgaria. Consequently, the soil moisture levels 

recent rainfall deficit in southern Bulgaria has started to 

for winter cereals remain at satisfactory level in northern 

deplete  the  upper  layer  soil  moisture  with,  however, 

Bulgaria,  while  they  are  decreasing  –  especially  in  the 

limited impact on crops so far. The crop yield outlook has 

upper soil layer – in southern Bulgaria. The cold weather 

been revised upwards for winter cereals. 

anomaly  in  April  slightly  slowed  down  the  phenological 

The colder-than-usual first half of April, during which an 

development of winter crops, which was advanced due to 

intensive cold spell event caused some local frost damage, 

mild  winter  conditions.  The  sowing  of  spring  crops  was 

was followed by warm weather during the second half of 

mainly finished in April.  

April  and  the  beginning  of  May.  A  rainfall  deficit  was 

In  general,  winter  cereals  are  currently  progressing  well 

recorded  especially  in  the  south-western  part  of  the 

despite the mild soil moisture deficit in southern Bulgaria; 

country,  while  a  rainfall  surplus  was  recorded  in  the 

our crop yield outlook has therefore been revised upwards. 

eastern part of Bulgaria. Overall, the rainfall events were 

The crop yield outlook for spring crops currently remains 

unevenly distributed, with a majority of rainfall recorded 

at the long-term average. 

during the first two dekads of April, while the subsequent 

23

 
 
 
 
 
 
 
 
JRC MARS Bulletin Vol. 29 No 5 –  25 May 2021 

Austria, Czechia, and Slovakia 
Average crop outlook despite very cold and dry spring 

Below-average  temperatures  in  April  and  begin  May 

slowed the development of winter and spring crops, and 

caused  delay  to  the  sowing  and  emergence  of  summer 

crops. May rains finally improved soil moisture conditions. 

The cold weather anomaly in April and the first dekad of 

May (with mean daily temperatures between 2°C and 3°C 

below  the  LTA)  was  followed  by  a  brief  warming  during 

the  second  dekad  of  May,  when  temperature  maxima 

exceeded  28°C.  Frequent  frost  events  occurred  in  April, 

with minimum temperatures dropping below -5°C during 

the first dekad of April. In most of Czechia, Austria, as well 

as in Western Slovakia, April was substantially drier than 

usual, causing soil moisture deficits to become even more 

pronounced after the very dry March. Precipitation events 

in  May  replenished  soil  moisture  levels  in  most  of  the 

regions. Global radiation was close to average. 

As  a  consequence  of  the  predominantly  below-average 
temperatures  in  April,  the  phenological  development  of 
winter crops became noticeably delayed as compared to 
an average year. Our model indicates that winter wheat is 
delayed in development by approximately 10 days (which 
is currently in stem elongation stage), and that  biomass 
accumulation  is  significantly  below  the  LTA.  In  addition, 
dry  and  cold  conditions  were  not  favourable  for  early 
development of spring crops, as well as for timely sowing 
of summer crops. Nevertheless, we maintain our previous 
forecast  for  winter  crops  (close  to  the  5-year  average). 
More  precipitation  and  adequate  thermal  conditions  are 
needed  in  the  weeks  to  come  to  allow  for  fair  yield 
formation  of  winter  cereals  and  to  sustain  the  forecast. 
Our outlook for spring and summer crops follows historical 
trends, under similar assumptions.

24

 
 
 
 
 
JRC MARS Bulletin Vol. 29 No 5 –  25 May 2021 

Denmark and Sweden 
Exceptionally cold period delays crop growth 

Colder  than  usual  conditions  slowed  down  growth  and 

good condition. Rainfall was particularly scarce during the 

development  of  winter  crops.  Spring  sowing  is  still 

last two dekads of April but increased above the average 

progressing  within  the  expected  window.  The  outlook  is 

totals at the beginning of May. 

positive despite the cold temperatures. 

According to our models, soil moisture levels are adequate 

The  period  was among the coldest of the last 30 years. 

Temperatures  dropped  below  average  and  were  lower 

than usual until the end of the first dekad of May. Frost 

conditions were frequent during the night. Due to the low 

temperatures, development of winter cereals, which was 

advanced  or  close  to  the  average  by  mid-April,  slowed 

down and currently is slightly below average expectations. 

Rapeseed  flowering  is  delayed  by  about  two  weeks. 

Similarly,  biomass  accumulation  of  winter  crops 

decreased  below  average  values.  However,  crops  are  in 

for  winter  crops  and  spring  cereals  benefitted  from  the 

rainfall at the beginning of May. 
In Denmark, the vast majority of spring barley and sugar 
beets  have  been  sown  before  mid-April  and  in  good 
seedbeds,  but  the  emergence  has  been  slow  due  to  the 
cold weather. Maize sowing started in May with variable 
progress across the country. In Sweden sowing is expected 
to be finished by the end of May, which is the usual time 
window  for  this  country.  The  yield  forecast  remains 
unchanged  with  respect  to  the  April  Bulletin  despite  the 
reduced crop growth that characterised the period.

25

 
 
 
 
 
JRC MARS Bulletin Vol. 29 No 5 –  25 May 2021 

Finland, Lithuania, Latvia and Estonia 
Sowings progress as usual despite cold weather 

Colder than usual temperatures slowed crop development, 

sugar  beets started at the end of April,  despite the cold 

but crops are in good conditions. Spring sowing activities 

and  rainy  weather.  In  the  rest  of  the  country  sowing  is 

progress  well  within  a  normal  window  despite  the  cold 

expected to be in full swing in mid-May, which is a normal 

weather. 

Cold 

temperatures  with 

frequent 

night 

frosts 

characterised  the  period,  although  unusually  warm 

weather occurred in April during the second dekad in the 

Baltic countries, and during the first two dekads in Finland. 

Since  10  May  warmer  than  usual  temperatures  have 

characterised all countries. Rainfall was slightly lower than 

the average in April and increased above average in May 

in the  Baltic countries; while  it was  higher than  usual in 

Finland. 

In  southern  Finland,  the  sowing  of  spring  cereals  and 

time  for  this  country.  In  the  Baltic  countries  sowings 

progress well, with limited interruptions in April, whereas 

the cold  weather slowed seed germination. Winter crops 

are  in  good  condition.  According  to  our  models,  crop 

development of winter cereals is currently slightly delayed 

despite  being  advanced  earlier.  Winter  rapeseed  is 

delayed by around 2 weeks. Crop growth indicators are in 

line with average values. Soil moisture levels are adequate 

for winter crops, and spring crops benefitted from the rain 

that fell at the beginning of May. 

Crop yield forecasts  remain  unchanged from last month 

and remain higher or close to the 5-year average.

26

 
 
 
 
 
JRC MARS Bulletin Vol. 29 No 5 –  25 May 2021 

Belgium, Luxembourg and the Netherlands 
Crops in fair condition despite continued cold weather

Colder-than-usual  weather 

conditions 

continued 

close to the LTA. 

throughout the period of review, causing crop growth and 

Winter crops are generally in fair condition, but growth and 

development  to  further  lag  behind.  Spring  sowing  was 

development  lagged  further  behind,  due  to  the  below 

completed within a suitable window but canopy formation 

average  temperatures.  Phenological  development  for 

has been slow. Soil-water conditions are adequate despite 

winter  cereals  is  about  one  week  delayed  and  biomass 

rain  deficit  in  Belgium.  Yield  forecasts  have  been 

accumulation is even further behind. On the positive side, 

essentially maintained. 

Below-average 

temperatures  continued 

to  prevail 

throughout  the  review  period,  making  this  the  coldest  1 

April to 15 May period in our records (since 1979) in most 

regions (in northern areas, the coldest since 1982). Only 

two days – 1  April and 9  May –  were  markedly warmer 

than usual. Frost events were common in the first half of 

April,  but  scarce  and  very  mild  since  then.  Rainfall  was 

below  average  in  April;  the  second  half  of  April  was 

practically  dry.  However,  above  average  rainfall  in  May 

resulted in rainfall totals that were close to the LTA for the 

period as a whole in most  parts of the  Netherlands, but 

with  a  deficit  (compared  with  the  LTA)  of  up  to  25  mm 

(locally  40  mm)  in  Luxembourg,  Belgium  and  the 

southernmost  parts  of  the  Netherlands.  Radiation  was 

as  rainfall  in  early  spring  was  high  and  crop  water 

demands have been low, soil water contents are currently 

above  average  in  all  regions  (even  in  the  south);  and 

current  mild  temperature  conditions  are  favourable  for 

crop  growth.  Spring  sowing  was  completed  within  a 

suitable  window,  but  emergence  and  early  development 

have been slow, which could result in a yield penalty for 

sugar beet. .Pest and disease pressure – which was very 

low  -  has  started  to  increase  due  to  the  current  mild 

temperatures  and  frequent  rain  events  since  the 

beginning of May. More settled weather will be welcomed 

by farmers to conduct phytosanitary measures. 

Our yield forecasts  have  been maintained at or close to 

the historical trend. 

27

 
 
 
 
 
 
 
JRC MARS Bulletin Vol. 29 No 5 –  25 May 2021 

Greece and Cyprus 
Yield forecasts for winter crops revised downwards

April’s  rainfall  in  Greece  favoured  a  gradual  recovery  of 

half  of  April,  while  well  distributed  episodes  of  rainfall, 

summer  crops,  but  the  positive  effects  on  winter  crops 

though scarce, characterised the first half of May. 

were insufficient to  compensate for the negative  effects 

The fairly favourable weather conditions in Greece during 

of earlier cold spells. Lack of rain in Cyprus hampered the 

the  current  review  period  have  been  insufficient  to 

yield expectations for barley.  

Predominantly  colder-than-usual  conditions  over  the 

major agricultural areas in northern Greece were observed 

in April. In the first ten days of May, daily temperatures 

sharply  increased  with  peaks  above  32⁰C  in  Thessaly, 

above 30⁰C in Macedonian regions on 2 May, and above 

32°C in Cyprus on 4 May. 

Precipitation totals during the period under review, from 1 

April to 15 May, were below the LTA in both countries. In 

Cyprus,  beneficial  and  well-distributed  rain  ceased  after 

10  April.  In  Greece,  specifically  in  Thessaly  and  the 

Macedonian regions, abundant rainfall fell in the second 

compensate for the damage caused to winter crops by the 

earlier cold wave episodes, which – on the basis of recent 

remote  sensing  observations  and  field  reports  from 

secondary  information  sources  -  appears  to  have  been 

more  serious  than  anticipated  in  the  April  Bulletin.  

Summer crops are gradually recovering. In Cyprus, remote 

sensing  observations  suggest  an  early  senescence  in 

barley, attributed to the lack of rain. 

Therefore,  our  forecasts  for  winter  crops  have  been 

lowered  for  both  countries,  while  our  forecasts  for 

summer  crops  (in  Greece)  still  follow  the  five-year 

average. 

28

 
 
 
 
 
 
JRC MARS Bulletin Vol. 29 No 5 –  25 May 2021 

Slovenia and Croatia 
Improved yield potential for winter cereals 

The intensive  cold  spell at the beginning of April caused 

crops, which is, after a favourably warm winter, currently 

substantial damage to flowering fruit trees and vineyards, 

close  to  the  long-term  average.  Above-average  rainfall 

but had only limited and localized impacts on winter crops. 

occurred 

in  Slovenia  and  Croatia 

in 

the  central 

Sufficient  soil  moisture  levels  are  supporting  good 

Kontinentalna Hrvatska and northern Jadranska Hrvatska 

progress of  winter  cereals,  allowing an  upwards revision 

regions. Sufficient soil moisture levels are supporting good 

of their crop yield outlook. 

The intensive cold spell bringing record-low temperatures 

during the first half of April caused considerable damage 

to flowering fruit trees and vineyards, as already reported 

in  the  April  Bulletin.  The  frost  damage  to  winter  cereals 

was  likely  limited  only  to  local  fields,  depending  on 

microclimatic  conditions.  Temperatures 

returned 

to 

normal  towards  the  end  of  April.  Colder  weather  during 

April slowed down the phenological development of winter 

progress  of  winter  cereals.  The  spring  crop  sowing 

campaign started delayed due to the cold conditions in the 

first  half  of  April.  Nevertheless,  improved  soil  moisture 

since  the  end  of  April  ensured  good  progress  of  spring 

crops, 

an 

adequate 

germination 

and 

uniform 

establishment. 

In conclusion, our crop yield outlook for winter cereals has 

been revised slightly upwards. The crop yield outlook for 

spring crops currently remains at the long-term average. 

29

 
 
 
 
 
 
JRC MARS Bulletin Vol. 29 No 5 –  25 May 2021 

5.2.  United Kingdom 

United Kingdom 
Exceptionally cold, dry, and wet 

Colder-than-usual  weather 

conditions 

continued 

Winter crops are generally in fair condition, but growth and 

throughout the period of review, whereas the exceptionally 

development lagged further behind, due to the continued 

dry April was followed by an extraordinarily wet first half 

below-average  temperatures.  Phenological  development 

of May. Crop growth and development have further lagged 

for winter cereals is about one week delayed and biomass 

behind.  In  our  assessment,  recovery  is  still  possible  and 

accumulation is even further behind. On the positive side, 

the  yield  forecasts  for  winter  cereals  and  spring  barley 

the April rain deficit did not impact winter crops; thanks to 

have been maintained. 

Below-average 

temperatures  continued 

to  prevail 

throughout  the  review  period,  making  this  the  coldest  1 

April to 15 May period in our records (since 1979). Only a 

few  days  -  most  markedly  9  May  –  were  warmer  than 

usual.  Frost  events  were  common  but  mild,  and  mostly 

confined to April. April was exceptionally dry, but the first 

half  of  May  was  exceptionally  wet,  resulting  in  rainfall 

totals that were close to the LTA for the period as a whole 

in most regions. Radiation was well-above the LTA in April 

and close to average in May. 

the  rain  in  May,  soil  water  contents  are  currently  above 

average  in  most  regions,  and  current  mild  temperature 

conditions are favourable for crop growth. The growth of 

spring  cereals  has  only  just  started  to  kick  off.  Some 

stands were negatively affected due to the frequent frost 

and dry top soils in April and may not fully recover. Pest 

and disease pressure – which was very low - has started 

to increase due to the mild temperatures and frequent rain 

events since the beginning of May. More settled weather 

will  be  welcomed  by  farmers  to  allow  them  to  conduct 

phytosanitary measures. 

30

 
 
 
 
JRC MARS Bulletin Vol. 29 No 5 –  25 May 2021 

5.3.  Black Sea Area 
Ukraine 
Cold weather not favourable for winter cereals 

The cold weather observed during the period under review 

observed last October. The yield forecast is slightly below 

was  not  particularly  favourable  for  winter  wheat  and 

the  historical  trend  considering  the  heterogeneous  crop 

spring  barley.  However,  since  the  beginning  of  May, 

conditions,  particularly  outside  of  the  main  producing 

conditions  have  been  favourable  for  summer  crops, 

regions. The cold weather observed in March and April is 

despite a slow start due to the cold temperatures. 

not favouring a good yield either, considering the average 

Cold  weather  prevailed  during  the  period  under  review, 

with temperatures between -1°C and -2°C below the LTA 

in most oblasts. While April was much colder than the LTA, 

temperatures returned to seasonal values in the beginning 

of May. Meanwhile rainfall was close to the LTA for the 

period  under  review,  with  a  slight  rain  deficit  in  eastern 

and  western  oblasts,  while  the  centre  received  slightly 

more rainfall than the LTA. 

Winter wheat is in good condition in eastern Oblasts and 

Odes’ka, while conditions are somewhat below average in 

other Oblasts, and particularly Vinnyts’ka, where emerging 

stands  were  negatively  impacted  by  the  heavy  rainfall 

temperatures  were  below  the  optimal  temperatures  for 

winter wheat. 

Winter barley is in good condition and the yield is expected 

to be close to the record-high level of 2019. Spring barley 

was sown relatively late and the cold temperatures since 

sowing have not been favourable to biomass formation.  

Grain  maize sowing is coming to an end, as well as the 

sowing  of  other  summer  crops;  considering 

that 

temperatures have been back at close to average levels 

since  the  beginning  of  May,  the  start  to  the  season  is 

beneficial.  

31

 
 
 
 
 
 
 
 
JRC MARS Bulletin Vol. 29 No 5 –  25 May 2021 

Turkey 
Crop growth delayed 

Winter  crops  forecast  remains  slightly  above  the  last  5-

May. From the beginning of May maximum temperatures 

year average, especially for soft wheat (+4%) and durum 

were  constantly  above  30°C,  while  precipitation  was 

wheat (+3%) due to a favourable season in south-eastern 

negligible  (<10  mm).  Irrigation  is  sustaining  winter  crop 

and  western-most  regions.  Summer  crops  season  just 

growth,  but  water  reservoirs  needed  for  the  summer 

started. 

season are already depleting. 

Since the beginning of April Anatolian agricultural regions 

have received 10 mm to 30 mm of rain, which is between 

50%  and  80%  below  the  usual  precipitation  amounts. 

Temperatures  increased  during  the  analysis  period  and 

moved  from  slightly  colder-than-usual  conditions  at  the 

beginning  of  April  to  above-average  temperatures  with 

anomalies  of  around  +4°C,  and  locally  up  to  +6°C, 

compared to the average. Ankara and Konya regions were 

among  the  driest  and  warmest,  increasing  irrigation 

demands. 

In south-eastern regions weather conditions were similar 

to in Anatolia, even though it was hotter with an average 

temperature  anomaly  of  +6°C  between  20  April  and  15 

In  central  and  western  regions  winter  crops  are  in 

contrasting  conditions:  weak  and  strongly  delayed  in 

Ankara  and  Konya,  while  favourable  in  Manisa  and 

Kiriklareli. 

In  eastern  Anatolian  regions  crops  are 

developing  well,  but  with  delayed  stages.  In  the  whole 

Anatolia region flowering is likely to occur later than usual 

in June, increasing the risk of heat stress at reproductive 

stages. 

In 

south-eastern 

regions 

irrigation 

is 

compensating  for  the  rain  deficit  while  the  high 

temperatures  could  have  a  minor  negative  effect  on 

reproductive  stages.  Concerns  for  the  summer  crop 

season are present throughout the whole country, due to 

the low level of irrigation reservoirs. 

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JRC MARS Bulletin Vol. 29 No 5 –  25 May 2021 

5.4.  European Russia and Belarus 

European Russia 
Improved conditions in south-western regions

Recent  abundant  precipitation  improved  the  condition  of 

okrugs  (Krasnodar,  Rostov,  Stavropol),  remote  sensing 

crops  in  south-western  parts  of  the  country,  but  did  not 

images indicate a significant improvement of the biomass 

bring any visible benefits to the crops grown in Central and 

accumulation in response to the overall positive conditions 

Volga okrugs. The spring sowing campaign is progressing 

of April, which allowed winter cereals to get back on track 

slowly.  

Most  areas  of  European  Russia  received  above-average 

precipitation in April, especially in the Southern and North 

Caucasian  okrugs,  which  received  more  than  80  mm 

(exceeding  the  LTA  by  25-40  mm).  This  allowed  soil 

moisture levels to restore from the record dry start to the 

season.  

Throughout  the  winter  wheat  belt,  temperatures  were 

close to the LTA during the period of review (1 April to 15 

May). Frost events were rare and mild.  

In the oblasts from the Southern and Northern Caucasian 

for  achieving  good  yields  if  weather  conditions  remain 

supportive. However, the images from the Central and the 

Volga okrugs did not show any visible improvement, which 

confirms the possible irreversible damage because of the 

bad  wintering  and  the  cold  spell  that  occurred  in  mid-

March.  

The  April  rains  also  benefited  the  emergence  of  spring 

crops that had already been sown. Dry and warm weather 

conditions  during  the  first  week  of  May  allowed  spring 

sowing  to  accelerate.  Nevertheless,  it  is  still  delayed 

compared to last year because of the wet soils.  

33

 
 
 
 
 
 
 
JRC MARS Bulletin Vol. 29 No 5 –  25 May 2021 

Belarus 
Good yield potential for winter cereals 

Below-average  temperatures  caused  a  slowdown  of 

soil moisture levels, while cumulative global radiation was 

winter 

crops’ 

development. 

Agro-meteorological 

slightly below the average.  

conditions  were  generally  favourable  for  sowing  spring 

Our model indicates some delays in the development and 

cereals  and  maize.  We  maintain  our  positive  yield 

biomass  accumulation  of  winter  wheat  due  to  colder-

expectations.  

Temperatures  oscillated  around  the  average  during  the 

first  two  dekads  of  April,  while  significantly  colder  than 

usual  conditions  dominated  at  the  end  of  April,  and  the 

first dekad of May. Frost events were frequent during the 

last  dekad  of  April,  but  temperature  minima  rarely 

dropped below -3°C. Total precipitation remained around 

the average in most of the country, allowing for adequate 

than-usual conditions during the third dekad of April and 

the first dekad of May. Nevertheless, currently there are 

no  concerns  for  winter  cereals.  While  sowing  of  spring 

cereals is close to being finalised, the sowing campaign of 

maize  started  during  the  third  decade  of  April,  under 

generally favourable agro-meteorological conditions. We 

maintain  our  positive  yield  outlook,  based  on  historical 

trends.  

34

 
 
 
 
JRC MARS Bulletin Vol. 29 No 5 –  25 May 2021 

5.5.  Maghreb 

Morocco, Algeria and Tunisia 
Negative outlook for cereals in central Maghreb, positive expectations in Morocco 

Favourable  precipitation  and  warm 
temperatures 
sustained cereal growth in Morocco, yield expectations for 
this  country  are  very  positive.  Dry  and  hot  conditions 
accelerated grain filling in the central-eastern regions of 
Algeria, deteriorating an already unfavourable campaign. 
Barley expectations continue to be negatively affected by 
the earlier drought for two inland regions of Tunisia. 

Winter cereals in Morocco are at the end of a very positive 
growing season. The current campaign started similarly to 
the  previous  (unfavourable)  season:  with  delays  in  the 
autumn 
rains  and  postponed  crop  sowings  and 
establishments.  But  unlike  the  previous  season,  January 
was rainier, with 90 mm of cumulated rain versus only 20 
mm  last  season  (average  for  the  cultivated  areas  at 
national  scale)  and  the  successive  February-May  period 
was  warm  and  characterised  by  frequent  and  evenly 
distributed rainfall events. Weather conditions supported 
crop  growth  and  development  along  the  vegetative, 
reproductive and grain filling phases. 
Crop conditions in Algeria further deteriorated during the 
period  under  review.  Temperature  sums  (Tbase  10°C) 

remained 20%-40% above the LTA in the most important 
agricultural areas and in addition, a rain deficit of 25 mm-
50  mm  was  observed  in  north-western  and  central 
regions, particularly in Relizane, Tissemsilt, Ain-Defla and 
Medea.  Analysis  of  remote  sensing  data  indicates  an 
acceleration  of  grain  filling  (e.g.  Sidi  Bel  Abbes,  Tiaret, 
Medea)  in  the  April-May  period.  This  occurred  at  the 
expense of the harvestable biomass. 
Winter  crop  conditions  in  Tunisia  remained  unchanged 
with  respect  to  the  previous  outlook.  Above-average 
rainfall  accumulation  and  daily  temperatures  1°C  -2°C 
above the LTA prevailed in the period under review. Crop 
biomass accumulation was in line with an average season 
in all the coastal and central regions, with the exception 
for  Kasserine  and  Kairouan  (20%  of  the  national 
production  of  barley)  where  below-average  biomass 
accumulation  has  been  observed  since  the  drought  in 
January and February. 
Our  forecasts  are  well  above  the  5-year  average  for 
Morocco, are revised downward in Algeria, and are around 
the last 5-year average for Tunisia 

35

 
 
 
 
 
 
JRC MARS Bulletin Vol. 29 No 5 –  25 May 2021 

6.  Crop yield forecast 

 
 
 
 
 
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JRC MARS Bulletin Vol. 29 No 5 –  25 May 2021 

 
 
 
 
 
 
 
 
 
JRC MARS Bulletin Vol. 29 No 5 –  25 May 2021 

7.  Atlas 

Temperature regime 

 
 
 
 
 
 
 
JRC MARS Bulletin Vol. 29 No 5 –  25 May 2021 

Precipitation 

 
 
 
 
 
 
 
JRC MARS Bulletin Vol. 29 No 5 –  25 May 2021 

 
 
 
 
 
 
 
JRC MARS Bulletin Vol. 29 No 5 –  25 May 2021 

Climatic water balance 

Crop development stages and precocity 

 
 
 
 
 
 
 
JRC MARS Bulletin Vol. 29 No 5 –  25 May 2021 

Relative soil moisture 

Maximum temperature around crop development 

 
 
 
 
 
 
 
JRC MARS Bulletin Vol. 29 No 5 –  25 May 2021 

Precipitation around crop development 

 
 
 
 
 
 
 
JRC MARS Bulletin Vol. 29 No 5 –  25 May 2021 

JRC MARS Bulletins 2021 

Date 

Publication 

25 Jan 
22 Feb 
15 Mar 

26 Apr 

25 May 

21 Jun 

26 Jul 

23 Aug 

20 Sep 

25 Oct 

22 Nov 

13 Dec 

Agromet analysis 
Agromet analysis 
Agromet analysis, yield 
forecast 
Agromet analysis, 
remote sensing, pasture 
analysis, sowing 
conditions, yield forecast 
Agromet analysis, 
remote sensing, pasture 
analysis, sowing update, 
yield forecast 
Agromet analysis, 
remote sensing, pasture 
analysis, rice analysis, 
yield forecast  
Agromet analysis, 
remote sensing, pasture 
analysis, harvesting 
conditions, yield forecast 
Agromet analysis, 
remote sensing, pasture 
update, harvesting 
update, yield forecast 
Agromet analysis, 
remote sensing, pasture 
analysis, rice analysis, 
harvesting update, yield 
forecast,  
Agromet analysis, 
pasture update, sowing 
conditions, harvesting 
update, yield forecast  
Agromet analysis, 
sowing update, 
harvesting update 
Agromet analysis 

Reference 

Vol. 29 No 1 
Vol. 29 No 2 
Vol. 29 No 3 

Vol. 29 No 4 

Vol. 29 No 5 

The JRC MARS Bulletin – Crop monitoring in Europe is a 
JRC–European Commission publication from 
MARS4CAST (JRC Unit D5 – Directorate for Sustainable 
Resources) 

JRC MARS Bulletins are available at 
https://ec.europa.eu/jrc/en/mars/bulletins 

JRC MARS Explorer for regularly updated maps and 
graphs https://agri4cast.jrc.ec.europa.eu 

Analysis and reports 
B. Baruth, S. Bassu, W. Ben Aoun, I. Biavetti, A. Ceglar, I. 
Cerrani,  Y.  Chemin,  M.  Claverie,  P.  De  Palma,  D. 
Fumagalli, R. Lecerf, G. Manfron, L. Nisini, L. Panarello, 
G. Ronchetti, L. Seguini, A. Toreti, M. van den Berg, M. van 
der Velde, Z. Zajac, A. Zucchini 

Vol. 29 No 6 

Reporting support  
SeproTec, I. Biavetti, G. Mulhern 

Vol. 29 No 7 

Vol. 29 No 8 

Vol. 29 No 9 

Vol. 29 No 10 

Vol. 29 No 11 

Edition  
M. van den Berg, B. Baruth, S. Niemeyer, M. van der Velde 

Data production 
MARS4CAST (JRC Unit D5), WENR (NL), MeteoGroup 
(NL), VITO (BE) 

Contact 
JRC D5/MARS4CAST  
JRCMARSBULLETIN@ec.europa.eu  

Legal notice 
Neither the European Commission nor any person acting on 
behalf of the Commission is responsible for the use, which 
might be made of this publication. 

Disclaimer 
The geographic borders are purely a graphical representation 
and are only intended to be indicative. The boundaries do not 
necessarily reflect the official European Commission position.   

Technical note  
The long-term average (LTA) used within this Bulletin as a 
reference is calculated on the basis of weather data from 
1991-2020.  

Pre-press version 
This is a pre-press version of the JRC MARS Bulletin, which, 
after final editing will be formally published by the 
Publications Office of the European Union.  

Vol. 29 No 12 

In terms of content, both versions are identical. 

Mission statement: As the science and knowledge service of 
the European Commission, the Joint Research Centre's mission 
is to support EU policies with independent evidence throughout 
the whole policy cycle.  

PDF: KJ-AW-21-005-EN-N ISSN 2443-8278 doi:10.2760/683215