Climate averages 1991–2020

Anchorage weather
in December.

A freezing month with moderate precipitation: the 11th warmest and the joint 8th driest of the year.

Long-term climate patterns, not a forecast for a particular trip.

Average high -5.1°C Daytime mean, December

Average low -9.4°C Night-time mean, December

Precipitation 73 mm 13 days with ≥1 mm

Daylight 6 h Sunrise to sunset, per day

December is a freezing month in Anchorage: daytime highs average -5.1°C and nights cool to about -9.4°C. By daytime temperature it is the 11th warmest of the 12 months.

Expect about 73 mm of precipitation on roughly 13 days, which makes December a month with moderate precipitation (the joint 8th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 5 h 39 min on an average December day.

Among the 498 cities listed in the United States, Anchorage ranks 498th of 498 for the warmest December highs and 260th of 498 for the driest December (precipitation, lowest first). The mean December high of those 498 cities is 10.5°C; Anchorage is 15.6°C cooler than that mean.

From December to January, average highs fall by 1.7°C to -6.8°C, and monthly precipitation falls from 73 mm to 50 mm.

The annual picture

December in context

30-year average

Average highAverage low°C

Monthly precipitation

Average total · mm

Averages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated

Every month, side by side

Anchorage climate table

1991–2020

Monthly climate averages for Anchorage, 1991–2020
Month	Average highHigh / low	Average low	Precipitation mm/month	Wet days ≥1 mm/day	Daylight hours/dayDaylight h/day
January	-6.8°C-10.9°C	-10.9°C	50	10.4	6.56 h
February	-3.9°C-8.5°C	-8.5°C	50	9.7	8.99 h
March	-1.2°C-7.2°C	-7.2°C	38	8.5	11.712 h
April	4.7°C-1.8°C	-1.8°C	29	7.3	14.715 h
May	10.1°C2.9°C	2.9°C	30	7.1	17.417 h
June	15.4°C9.0°C	9.0°C	40	8.9	19.219 h
July	17.3°C11.9°C	11.9°C	73	12.5	18.418 h
August	16.3°C11.0°C	11.0°C	107	14.8	15.916 h
September	11.8°C6.7°C	6.7°C	117	15.3	13.013 h
October	4.4°C-0.2°C	-0.2°C	90	13.2	10.110 h
November	-2.6°C-6.8°C	-6.8°C	66	11.7	7.47 h
December, selected	-5.1°C-9.4°C	-9.4°C	73	12.9	5.66 h

Precipitation (rain or snow, as water) is the average of the 30 separate monthly totals. A wet day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.

Read the numbers correctly

Climate, not a promise.

These patterns help compare months. They cannot tell you the weather on a specific day of your trip.

Sources, method and limits

How these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Anchorage) is explained once on the Anchorage year overview and on the Sources, method and limits page.