Climate averages 1991–2020
Anchorage weather
in August.
A mild, wet month: the 2nd warmest and the 11th driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
August is a mild month in Anchorage: daytime highs average 16.3°C and nights cool to about 11.0°C. By daytime temperature it is the 2nd warmest of the 12 months.
Expect about 107 mm of rain on roughly 15 days, which makes August a wet month (the 11th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 15 h 51 min on an average August day.
Among the 498 cities listed in the United States, Anchorage ranks 498th of 498 for the warmest August highs and joint 430th of 498 for the driest August (rainfall, lowest first). The mean August high of those 498 cities is 29.9°C; Anchorage is 13.6°C cooler than that mean.
From August to September, average highs fall by 4.5°C to 11.8°C, and monthly rainfall rises from 107 mm to 117 mm.
The annual picture
August in context
Monthly precipitation
Average total · mmAverages 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
| 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, selected | 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 limitsHow 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.