Contacts: Molly Woloszyn (mollyw@illinois.edu)

 Samantha Borisoff (samantha.borisoff@cornell.edu)

Great Lakes Region Quarterly Climate Impacts and Outlook / June 2013 (experimental)

 www.drought.gov/drought/content/resources/reports

Quarterly Climate Impacts 

and Outlook

Great Lakes Region

June 2013 (Experimental)

Great Lakes Significant Events - for March - May 2013

Precipitation and Temperature Great Lakes Water Levels

Regional Climate Overview - for March - May 2013

The 2013 spring season was wet and cool across 

the Great Lakes region. However, despite above 

average spring precipitation and subsequent water 

level rise, water levels on lakes Superior, Michigan, 

and Huron remain below average. Water levels on 

lakes Erie and Ontario remain at or near their longterm average.

Cooler spring temperatures caused ice-out on 

lakes to occur several weeks later than normal in 

Minnesota and other portions of the region, coming just one year after ice-outs that were among 

the earliest on record in 2012. 

A noteworthy ice shove event occurred this spring 

on Mille Lacs Lake in Minnesota on May 11th, 

where strong winds pushed partially melted ice 

onshore from the lake surface. Ice piled 1.5 to 9 m 

high (5 to 30 ft), which caused extensive damage to 

several homes along the shoreline.

Due to a strong storm system that brought heavy 

precipitation through the region on April 17th19th, severe localized flooding and record-breaking 

river flooding occurred across portions of Wisconsin, Illinois, lower Michigan, northern Indiana, and the Muskoka region of Ontario (central 

Ontario). Storm event severity ranged from a 1 in 25 year event to 1 in 100 year event in some locations.

Despite above average precipitation this 

spring, water levels remain below average 

on lakes Superior, Michigan, and Huron. Even 

though Lake Michigan-Huron water levels rose 

by 24 cm (9.5 in.) in April and another 13 cm 

(5 in.) in May, Lake Michigan-Huron remains 

the lowest of the lakes relative to its long-term 

average around 50 cm (20 in.) below at the end 

of May. Lake Superior had the second largest 

May rise on record of 24 cm (9.5 in.), but at the 

end of May, still remained about 18 cm (7 in.) 

below its long-term average. 

The Great Lakes U.S. basin received 267.5 

mm (10.53 in.) of precipitation, 124% of 

normal, making it the 9th wettest spring on 

record. Twenty of the 25 climate divisions 

were wetter than normal with 11 ranking 

spring 2013 among their top 10 wettest. 

In fact, with 169% of normal precipitation, 

central lower Michigan reported its wettest 

spring on record. The Canadian side of 

the Great Lakes received above normal 

precipitation as well. The north side averaged 

250-300 mm (9.8-11.8 in.), which is 115-

150% of normal.

With an average temperature of 5.2°C 

(41.4°F), it was 1.3°C (2.4°F) below normal on 

the southern side of the Great Lakes basin. 

Of the 25 climate divisions that make up the 

southern side, 22 were cooler than normal 

with four ranking this spring among their top 

10 coolest. On the northern side of the basin, 

temperatures varied with Southern Ontario 

averaging 5-10°C (41-50°F) and areas north of 

Lake Superior averaging -2-0°C (28.4-32°F).

U.S. normals based on 1981-2010 and 

Canadian normals based on 1971-2000.

Total Precipitation

3/1/2013-5/31/2013

Average Temperature

3/1/2013-5/31/2013

Grand Traverse Bay, MI (1/11/13)

Photo: Michigan Sea Grant

Water level statistics based on the 1918-2012 

period of record.
Regional Impacts - for March - May 2013

Regional Outlook - for Summer 2013 Great Lakes Region Partners

Environment Canada

www.ec.gc.ca

Agriculture and Agri-Food Canada

www.agr.gc.ca 

Midwestern Regional Climate Center

www.mrcc.isws.illinois.edu

Northeast Regional Climate Center

www.nrcc.cornell.edu

Great Lakes Region State Climatologists

www.stateclimate.org

National Oceanic and Atmospheric Administration

www.noaa.gov

National Climatic Data Center

www.ncdc.noaa.gov

National Ocean Service

www.oceanservice.noaa.gov

National Operational Hydrologic Remote Sensing Center

www.nohrsc.nws.gov

Great Lakes Environmental Research Laboratory

www.glerl.noaa.gov

NOAA Great Lakes Sea Grant Network 

www.seagrant.noaa.gov

North Central River Forecast Center

www.crh.noaa.gov/ncrfc

NOAA’s Great Lakes Regional Collaboration Teams

www.regions.noaa.gov

Climate Prediction Center

www.cpc.noaa.gov

Great Lakes Integrated Sciences & Assessments 

Center

www.glisa.umich.edu

US Army Corps of Engineers

www.usace.army.mil

National Integrated Drought Information System 

www.drought.gov

Great Lakes Water Level Dashboard

www.glerl.noaa.gov/data/now/wlevels/dbd/

#regionalclimateoutlooks

Contacts: Molly Woloszyn (mollyw@illinois.edu)

 Samantha Borisoff (samantha.borisoff@cornell.edu)

Great Lakes Region Quarterly Climate Impacts and Outlook / June 2013 (experimental)

 www.drought.gov/drought/content/resources/reports

Lake Level Outlook Harmful Algal Blooms 

Outlook 

Great Lakes water levels, with the exception 

of Lake Ontario, are expected to remain 

below average throughout summer 2013 

(JJA), with the level of Lake Michigan-Huron 

expected to remain 39 to 59 cm (15 to 23 

in.) below its long-term average. Anticipated 

impacts of prolonged low water levels include 

undercutting of shore protection, increased 

dredging, and navigational hazards.

Increased 

precipitation, 

as what was 

experienced 

this April, could 

lead to more 

persistent and 

widespread 

harmful algal 

blooms in 

Lake Erie 

this summer. 

Recently, a potential algal bloom in Lake 

Superior was also discovered. The presence 

of algal blooms in the Great Lakes could 

have an immediate impact on tourism and 

local economies as algae is aesthetically 

unappealing to recreationists and there are 

foul odors associated with algal blooms and 

mats in the nearshore.

Agriculture

Wet and cool conditions in April and early May delayed the start of 

the planting season for farmers in the region. The cool spring also 

led to some delays in development of tree fruit in Michigan. More 

favorable conditions in May allowed planting to rapidly progress 

and warmer temperatures also helped tree fruit develop to normal 

growth stages for this time of year.

A late May frost in Ontario resulted in damage to 4.5% of corn acres, 

4% of soybean acres, 2% of tobacco, and 8% of tomato according 

to Agri-corp (www.agricorp.com). It is difficult to say how much the 

frost could cost, but it has been a rough spring so far in Ontario for 

vegetation. 

Transportation

The low water levels continue to have an impact on transportation 

across the Great Lakes, specifically the shipping industry. Large 

vessels are having to reduce their cargo loads because of the low 

water levels, therefore reducing 

potential revenue. In Ontario, the 

start of the Chi-Cheemaun ferry 

season, which is the main source of 

transportation between Bruce Peninsula 

and Manitoulin Island, was delayed by 

two weeks from its typical May 3rd start 

as low water on Lake Huron caused 

docking problems for the ferry. 

Recreation and Tourism

Record late ice-outs on lakes across the upper Great Lakes has had 

an impact on fishing season openers, reducing the revenue typically 

generated this time of year from recreation and tourism. The Lake 

Superior fishing season opener had record low attendance this year 

because of lingering ice, extremely cold water temperatures, and 

high winds, all of 

which also became 

safety hazards. 

Outlook from the US Army Corps of Engineers 

and Environment Canada (Summer 2013) 

Left: Lake Bemidji (MN) 

on May 8th; Photo courtesy of Tom Robertson/

MN Public Radio

Left: Corn showing steady growth 

in northern Indiana in early June 

2013; Photo courtesy of Justin 

Leighty (In the Field)

Temperature & Precipitation Outlook 

In Ontario, outlooks from Environment Canada (EC) indicate that above normal temperatures 

are anticipated in portions of central Ontario, with near normal elsewhere. EC forecasts above 

normal precipitation throughout Ontario this summer. In the U.S., the Climate Prediction Center 

(CPC) outlooks indicate no appreciable chances for above or below normal temperatures or 

precipitation throughout the summer.

Above: The Chi-Cheemaun ferry