UQIAĠVIK: Sep 28-30: US$10 

million damage from coastal 

erosion from Arctic storm

ALASKA and NORTHWESTERN CANADA 

Weather and Climate Highlights and Impacts, Sept - Nov 2017; Climate Outlook Jan 2018 - Mar 2018

1

FT. ST. JOHN: Record 

breaking snowfall of 55 cm 

(2.2”) in Fort St-John on 

Oct 24-25

DAWSON: Fifth wettest Sep-Nov 

on record: 130 mm (5.1”)

OLD CROW: 5th warmest Oct 

on record with an average 

temp of -5.2°C (22.6 °F)

BC/YUKON: Arctic outbreak 

began Nov 2. More than 30 

daily low temp records set

FAIRBANKS: Oct 09-10: 1.54” 

(39.1mm) pcpn is the max 24 hour 

pcpn of record in the autumn

BEAUFORT/CHUKCHI SEAS: Near to 

record low autumn sea ice extent

ANCHORAGE: Sep 13 

min temp 55°F (13°C) 

is the highest min so 

late in the season

HYDER: Sep 5 max temp 84°F (29°C) 

just one degree Fahrenheit shy of 

state record for month

SHISHMAREF: 

Severe erosion 

from storm 

Nov 11-12, 

disaster 

declared

ST. PAUL: 

Warmest Nov 

since 1926 with 

average temp 

39.4°F (4.1°C)
Temperature & Precipitation, Sept 2017 – Nov 2017

Source: NOAA and ECCC 2

Source: NOAA and ECCC 

A moist weather system overriding a cold airmass in the Peace region resulted in record-breaking

snowfall in Fort St. John. A total of 55cm of snow was recorded at the airport in less than 24 hours. The

event began the evening of October 24th and continued into the early hours of October 25th with

residents waking up to a winter wonderland as shown in the photograph. Photo credit – Julie Rogers

CBC.

Waves crash on the coast at Utqiaġvik on the morning of September 29th. Although the associated storm

system was only moderately strong, a virtually unlimited fetch of wind over the ice free Chukchi Sea to

the west of Utqiaġvik pushed water onshore and caused enough damage for the state to issue a disaster

declaration as a result of an estimated US$10 million damage. Photo credit: U. of Alaska.

Much of mainland Alaska, northern Yukon Territory and large swath of the western NWT was significantly

warmer than average for autumn 2017. Most of the remainder of the region had, on average, near normal

temperatures, except for a small swath from the central Yukon Territory south and eastward into the

northern Alaska Panhandle and northern British Columbia, where temperatures averaged significantly

below normal. Total precipitation was significantly above average over much of northern and western

sections and northeast British Columbia, but below normal along the Gulf of Alaska coast into northwest

British Columbia and parts of the Yukon and Northwest Territories.

Wet

Wet

Dry

Dry

Above

Normal

Above

Normal

Below

Normal

Near

Normal
Impact of weak to moderate La Niña to Pacific NW and Alaska 

Sharp warming in air temperature at Utqiaġvik flagged as artificial change

A typical La Niña winter pattern features high pressure across the Bering Sea that reduces the

numbers of storms tracking into the region and is favorable for the development of a colder than

normal airmass across northwest North America. This is in contrast to El Niño, when a storm

track into the northeast Pacific and Gulf of Alaska is favored, bringing milder air into northwest

North America, and near the coast increased precipitation. La Niña sometimes features large

swings in the week to week weather pattern, which again is in contrast to El Niño winters, where

the weather pattern is often very stable for long stretches of time.

Under a weak La Niña climate pattern, most of NW Canada may experience colder than average

temperatures, while the South Coast of BC may experience above-average precipitation.

These graphics show departures from the long term averages for January through March during eight winters between

1979 and 2016 when there was a weak to moderate La Niña. Most of North America west of the MacKenzie River

finished up cooler than average during late winter season. Western Alaska has averaged drier than average during

recent La Niña, while most of the remainder of the region has tilted toward higher precipitation. Even in these eight

winters (1984, 1985, 1996, 1999, 2001, 2008, 2011 and 2012), there is significant variation in most areas.

3

La Niña likely to make a return this winter

Air temperature at Utqiaġvik (Barrow) increased by up to

7.8°F (4.3 °C) between 1979-1999 and 2000-2017 for the

months of October-December. This warming was large

enough to trigger an algorithm designed to detect artificial

changes in a station’s instrumentation or environment and

disqualify the entire 2017 air temperature measurements. The

warming was a result of decreasing sea ice area in the

Chukchi and Beaufort Seas, exposing more relatively warm

Arctic water to the atmosphere than when sea ice in the

region is large. The discarded Utqiaġvik data is progressively

restored and incorporated in the National Centers for

Environmental Information Alaskan temperature to reflect the

climate change that changed the environment. Additional

information can be found here.

Courtesy NWS/NCEP Climate Prediction Center

Average annual temperature in °F at Utqiaġvik, Alaska, from

1925 through 2016. The annual values for 1929, 1941 and 1989

are not plotted because of some missing data during those

years. Adapted from NOAA.
Temperature Outlook: Jan - Mar 2018 Precipitation Outlook: Jan - Mar 2018

The calibrated categorical forecasts from the 100 plus member North

American Multi-Model for January-March 2018 show increased chances

for significantly below normal temperatures over northern British

Columbia, the central and southern Yukon Territory, westernmost NWT

and adjacent areas on southeast Alaska mainland and Panhandle. The

only area with increased chances for significantly above normal

temperatures are small areas in coastal western Alaska., which is

consistent with the expectations during a La Niña winter.

Precipitation forecasts show a wet tilt across northwest Alaska and the

western Interior. In contrast, from Kodiak Island eastward into the

northern Alaskan Panhandle, extreme northwest British Columbia and

parts of the Yukon and southwest NWT there are slightly increased

odds for significantly below normal precipitation.

Content and graphics prepared in partnership with the Western Region Climate Center, NOAA National Weather Service Alaska 

Region, and Environment and Climate Change Canada. 

ALASKA REGION PARTNERS: Western Region Climate Center, Alaska Climate Research Center, Alaska Climate Science Center, 

Cryosphere Today, NOAA / NWS Weather Forecast Offices, NOAA / NESDIS / NCEI, Scenarios Network for Alaska + Arctic Planning. 

NOAA ALASKA REGION CONTACTS: 

JAMES PARTAIN james.partain@noaa.gov

RICK THOMAN richard.thoman@noaa.gov

ncei.noaa.gov • #regionalclimateoutlooks

BRIAN BRETTSCHNEIDER: WRCC 

brbrettschneider@alaska.edu

PETER BIENIEK

pbieniek@alaska.edu

WESTERN CANADA CONTACTS: 

Environment and Climate Change Canada 

(ECCC). 

LISA WEST lisa.west@canada.ca 

ERIK de GROOT erik.degroot@canada.ca

GABRIELLE GASCON 

gabrielle.gascon@canada.ca

MATT MACDONALD 

matt.macdonald@canada.ca 4

Sea Ice Conditions at the end of November 2017 in the Beaufort and Chukchi Seas

Sea ice continued to recede away from Alaska during September, with

no ice within 100 miles (160km) of Alaska at the end of the month. Ice

grew only slowly during October and November. This lack of ice allowed

for several late season coastal flood and severe erosion events to

impact some western Alaska communities. The Beaufort was largely

iced over mid-November, but open water stubbornly persisted in the

Chukchi Sea. By the end of November there was still open water far to

the northwest of Utqiaġvik. The combined Chukchi and Bering sea ice

extent was only half of the 1981-2010 average and the lowest on record

in the satellite era (since 1978) (data from National Snow and Ice Data

Center).

Following a greater than normal ice melt for the Beaufort Sea areas this

past summer, the onset of freeze up was significantly delayed.

Generally speaking ice formation over the area was 3-4 weeks later

than normal. However by mid-December, the area was almost entirely

covered with ice (no significant departure as shown on the map). With

the delayed ice formation, ice thicknesses were also thinner than

normal. At the end of the melt season, this year ranked as the 7

th lowest

minimum ice extent in the Beaufort Sea area.