Anchorage, Alaska (Dena'ina: Dgheyay Kaq'; Dgheyaytnu) has a subarctic climate with the code Dsc according to the Köppen climate classification due to its short, cool summers. The weather on any given day is very unpredictable. Some winters feature several feet of snow and cold temperatures, while the summers are typically mild but are cool compared to the contiguous US and interior Alaska. Because of Anchorage's high latitude, summer days are very long and winter daylight hours are very short. The longest day of sunlight being 19hrs and 21 minutes, and shortest being 5 hours and 28 minutes. Anchorage is often cloudy during the winter, which decreases the amount of sunlight experienced by residents.

Temperature

Averages

Average daytime summer temperatures range from approximately ; average daytime winter temperatures are about . Anchorage has a frost-free growing season that averages slightly over one hundred days. Average January low and high temperatures at Ted Stevens Anchorage International Airport (PANC) are 11 / 23 °F (−11.7 / −5.0 °C) with an average winter snowfall of 75.59 inches, or 1.92 meters. Farther afield at the Campbell Airstrip is another weather station recording colder night temperatures in both summer and winter.

Average July low and high temperatures are 52 / 66 °F (11.1 / 18.9 °C) and the hottest reading ever recorded was 90 °F or 32.2 °C on July 4, 2019.

Highest daily temperatures PeriodRecord temperatureDate January 27, 2014January 19, 1961 Feb 27, 2014 Mar 31, 2016 Apr 29, 2005 May 21, 2002May 24, 1969 Jun 14, 1969 Jul 4, 2019 Aug 2, 1978Aug 21, 1977Aug 6, 1968 Sep 5, 1957 Oct 9, 2006 Nov 26, 2002 Dec 9, 2019

Lowest daily temperatures PeriodRecord temperatureDate Jan 5, 1975 Feb 4, 1999 Mar 7, 1971 Apr 2, 1985 May 10, 1964 Jun 4, 1961 Jul 1, 1964 Aug 31, 1984Aug 28, 1984 Sep 24, 1992 Oct 31, 1956 Nov 17, 1956 Dec 27–28, 1961Dec 14, 1964

Daily record warm minima

PeriodRecord temperatureDate Jan 20, 1990 Feb 25, 1978 Mar 26, 1970 Apr 27, 2015Apr 29, 2005 May 31, 1993 Jun 16, 2015 Jul 10, 2005 Aug 13–14, 2019 Sep 6, 1993Sep 5, 1965 Oct 10, 1986 Nov 9–10, 1979 Dec 11, 2017Dec 28, 1982

Daily record cold maxima

PeriodRecord temperatureDate Jan 28, 1989 Feb 3–4, 1999 Mar 7, 1971 Apr 1, 1985 May 9, 1964 Jun 1–2, 1973 Jul 27, 1971 Aug 21, 1985Aug 25, 1983 Sep 30, 1992 Oct 31, 1975 Nov 29–30, 1990 Dec 28, 1961

Precipitation

Rainfall Between 2000 and 2022 the annual rainfall in Anchorage was . The months with the highest average mean of rain were August and September, each having an annual mean of (August) and (September).

Snowfall

For snowfall, the annual mean average for 2000 to 2022 was 194 centimeters or 76.4 inches; the highest snowfall season being 2011 - 2012 with , and the lowest season being inches in 2015.

Climate change Based on the ERA5 data published by ECMWF, the annual mean temperature of Anchorage has increased from 0.8 °C in 1940 to 3.8 °C in 2022, an increase of 3 °C. The mayor and the assembly of Anchorage in 2019 issued a climate action plan for the anticipated effects that climate change will have on its city and people. The action plan includes all of the municipality of Anchorage, as far north as Eklutna and as south as Portage. One of the major goals of the climate action plan is to reduce green house gas emissions by 80% by the year 2050 from its 2008 emission levels. The first annual report on this came out in 2021. For its near term plans, the city also introduced a plan called the "Municipality of Anchorage Climate Action Strategy."

Notable climate events Due to its proximity to active volcanoes, ash hazards are a significant, though infrequent, occurrence. The most recent notable incident was an August 1992 mark of Mt. Spurr, which is located west of the city. The eruption deposited about of volcanic ash on the city. The cleanup of ash resulted in excessive demands for water and caused major problems for the Anchorage Water and Wastewater Utility.

On March 17, 2002, there was a storm that caused of snow to close schools for two days. The storm broke the city record for the most snowfall in a single day. The storm beat the previous record from 1955 on March 16, which was just . The National Weather Service also recorded this same snow data.

Classifications

Trends in temperature, precipitation, and daylight hours

NWS office/international airport

Campbell airstrip

Merrill Field

Notes

References