Climate averages 1991–2020

Anchorage weather
in May.

A cool, fairly dry month: the 5th warmest and the 2nd driest of the year.

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

Average high 10.1°C Daytime mean, May

Average low 2.9°C Night-time mean, May

Rainfall 30 mm 7 days with ≥1 mm

Daylight 17 h Sunrise to sunset, per day

May is a cool month in Anchorage: daytime highs average 10.1°C and nights cool to about 2.9°C. By daytime temperature it is the 5th warmest of the 12 months.

Expect about 30 mm of rain on roughly 7 days, which makes May a fairly dry month (the 2nd driest of the 12 months). Daylight, from sunrise to sunset, lasts about 17 h 26 min on an average May day.

Among the 498 cities listed in the United States, Anchorage ranks 498th of 498 for the warmest May highs and 129th of 498 for the driest May (rainfall, lowest first). The mean May high of those 498 cities is 23.8°C; Anchorage is 13.7°C cooler than that mean.

From May to June, average highs rise by 5.3°C to 15.4°C, and monthly rainfall rises from 30 mm to 40 mm.

The annual picture

May 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, selected	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	-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.