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Glennallen, AK Climate

Temperature, precipitation, and comfort score from NOAA NCEI 1991-2020 normals →

30-year climate normals from 1 weather station (1991-2020).

Glennallen, Alaska has an average annual temperature of 26°F and a climate comfort score of 47/100 (Moderate). Annual precipitation totals 18.7". Based on NOAA 30-year normals (1991–2020).

Avg Temperature

26°F (-4°C)

Avg High

36°F

Avg Low

15°F

Annual Precip

18.7"

Comfort Score

47/100

Moderate

Climate Comfort Score

47/100

Moderate

Avg Annual Temperature

26°F

30-year mean (NOAA NCEI)

Annual Precipitation

18.7"

Liquid-equivalent total

Comfort score vs national 100-point ceiling (Glennallen) 47.0%
National median (≈55)

PlainClimate composite — temperature mildness, humidity, precipitation, extreme-weather frequency. Moderate for the Glennallen area.

Warming context for Glennallen

Methodology

How the U.S. land temperature anomaly tracks against the global mean since 1900. The current NOAA 1991-2020 normal for Glennallen captures average conditions across the spread shown — the most recent decade is warmer than the 30-year mean.

Warming context — U.S. vs global, with Paris reference lines Anomaly chart from 1900 to 2024. Local series shows warming of 0.11 °C per decade versus a global rate of 0.11 °C per decade (ratio 1.00). Paris Agreement thresholds at 1.5 and 2.0 °C are dashed. -1.0°C -0.5°C +0.0°C +0.5°C +1.0°C +1.5°C +2.0°C +2.5°C Paris 1.5°C Paris 2.0°C 1900192019401960198020002020
  • United States land mean (NOAA NCEI) +0.11 °C/decade
  • Global anomaly (NASA GISTEMP) +0.11 °C/decade
  • Paris Agreement thresholds 1.5°C / 2.0°C
Sources: NOAA NCEI, NASA GISTEMP. Paris thresholds per IPCC AR6 WG1.

Monthly Temperatures

Average daily high and low temperatures by month

Month Avg High Avg Low Mean
January 7°F (-14°C) -10°F (-23°C) -2°F (-19°C)
February 15°F (-9°C) -7°F (-22°C) 4°F (-15°C)
March 22°F (-5°C) -3°F (-19°C) 10°F (-12°C)
April 37°F (3°C) 15°F (-9°C) 26°F (-3°C)
May 51°F (11°C) 30°F (-1°C) 40°F (5°C)
June 63°F (17°C) 39°F (4°C) 51°F (10°C)
July 66°F (19°C) 43°F (6°C) 55°F (13°C)
August 60°F (16°C) 40°F (4°C) 50°F (10°C)
September 51°F (10°C) 31°F (0°C) 41°F (5°C)
October 33°F (0°C) 16°F (-9°C) 24°F (-4°C)
November 15°F (-10°C) -4°F (-20°C) 6°F (-15°C)
December 11°F (-12°C) -9°F (-23°C) 1°F (-17°C)

Monthly Precipitation

Average monthly rainfall

January 0.9"
February 0.5"
March 0.8"
April 0.6"
May 1.1"
June 2.5"
July 3.1"
August 3.0"
September 2.4"
October 1.2"
November 1.4"
December 1.2"

Frost Dates & Growing Season

First Fall Freeze

August 24

50% probability date

Last Spring Freeze

June 5

50% probability date

Heating & Cooling Degree Days

Annual totals indicate energy demand for heating and cooling

Heating Degree Days

14,388

Higher = more heating needed

Cooling Degree Days

1

Higher = more cooling needed

Warmest Month

July

Coldest Month

January

Related Data

Climate Guides

Climate Insight: Glennallen, AK

The NOAA 1991–2020 climate normals describe Glennallen, Alaska as a location with an annual average temperature of 26°F, ranging from a mean daily high of 36°F to a mean daily low of 15°F. July is typically the warmest month of the year, while January is the coldest. These thirty-year averages, computed from station USW00056401, smooth out year-to-year variability and give a baseline expectation for typical conditions in any given month.

Precipitation patterns matter as much as temperature for anyone planning to live, garden, or travel here. Glennallen receives roughly 18.7 inches of precipitation each year, predominantly as rainfall. Growing-season length varies with elevation and microclimate, with the last spring freeze near June 5 and the first fall freeze near August 24. For energy use, 14,388 heating degree days and 1 cooling degree days tell the story of how often furnaces and air conditioners run during a normal year.

On PlainClimate's composite comfort index, Glennallen scores 47/100 (Moderate), a blended measure that weighs temperature mildness, precipitation moderation, and extreme-weather frequency against one another. Use the monthly tables above to plan around specific windows — shoulder seasons for mild highs and lows, peak summer for July-driven heat, or deep winter for January-driven cold. All figures here are thirty-year averages: any single year may run warmer, wetter, drier, or cooler than the normal, so treat them as planning guidance rather than forecasts.

Frequently Asked Questions

What is the average temperature in Glennallen, AK?
The average annual temperature in Glennallen, Alaska is 26°F. The warmest month averages 66°F (19°C) and the coldest averages -10°F (-23°C).
How much rain does Glennallen get?
Glennallen receives 18.7 inches of precipitation annually. Based on NOAA 30-year climate normals (1991-2020).
What is the comfort score for Glennallen?
Glennallen has a climate comfort score of 47/100 (Moderate). This score considers temperature mildness, humidity, precipitation, and extreme weather frequency.
When is the growing season in Glennallen?
Growing season data is not available for Glennallen.
How much energy does heating and cooling require in Glennallen?
Glennallen has 14,388 heating degree days and 1 cooling degree days annually. Higher heating degree days indicate greater winter energy demand, while higher cooling degree days indicate greater summer cooling needs.
Where does this Glennallen climate data come from?
All climate data comes from NOAA U.S. Climate Normals v1.0.1, covering the 30-year period from 1991 to 2020. Data is collected from weather station USW00056401. These 30-year averages are the standard reference for typical weather conditions.

Data Sources

Data source: NOAA U.S. Climate Normals v1.0.1 (1991-2020). Station: USW00056401. For informational purposes only.

Related

Data sourced from official public datasets. See our methodology for details. Retrieved and formatted by PlainClimate Editorial