Alaska

Big Delta, Alaska Climate

NOAA 1991-2020 normals for Whitestone Farms, 2.3 km from Big Delta

The warmest month is July, with an average high of 74°F; the coldest is January, with an average low of -11°F. A normal year brings 12.7 in of precipitation and 41.5 in of snow.

Temperature through the year

The normal daily high and low and the record for every date at Ft.Greely/Allen Aaf (Asos) (PABI), since 1917. The line marks today.

Normal daily high and low temperature at Big Delta through the year, in °F, with the record for each date.-100-50050100JanFebMarAprMayJunJulAugSepOctNovDec
  • Normal low
  • Normal high
  • Record high
  • Record low

Normals for Sep 24

Normal high
51°F
Normal low
32°F
Record high
73°Fin 1942
Record low
10°Fin 1992
Chance of a wet day
35%
Daylight
12 h 03 min

Month by month

Averages for 1991-2020. Wet days have at least 0.01 inch of precipitation. Freeze nights have a low of 32°F or colder; degree days are on a 65°F base. Each month links to its own page.

MonthAvg highAvg lowRecord highRecord lowPrecipitationWet daysSnowfallFreeze nightsHeating DDCooling DD
January6°F-11°F54°F (2009)-63°F (1947)0.44 in8.05.7 in30.92,0910
February16°F-4°F51°F (2003)-60°F (1947)0.32 in5.95.0 in27.91,6540
March27°F1°F58°F (1981)-49°F (1964)0.33 in5.63.7 in30.21,5730
April48°F21°F72°F (1979)-37°F (1944)0.24 in4.21.6 in27.29150
May63°F34°F90°F (1947)-1°F (1945)0.84 in7.91.1 in13.25100
June73°F45°F92°F (1969)26°F (2006)2.51 in13.20.0 in0.619812
July74°F49°F91°F (1958)32°F (1971)2.75 in15.20.0 in0.012918
August67°F44°F90°F (1994)22°F (1948)2.13 in15.10.0 in1.53011
September56°F35°F79°F (1963)-2°F (1983)1.16 in10.61.7 in12.85990
October34°F18°F74°F (2003)-39°F (1975)0.80 in9.97.3 in26.71,2040
November15°F-1°F52°F (1979)-47°F (1986)0.66 in9.18.7 in30.01,7380
December10°F-8°F55°F (1985)-62°F (1946)0.51 in8.16.7 in31.01,9890
Year41°F19°F12.69 in11341.5 in23212,90031

Precipitation

Rain and melted snow together. The chance of a wet day is the share of days with at least 0.01 inch of precipitation.

12.7 in in a normal year, most in July.

Chance of a wet day

The chance of at least 0.01 inch of precipitation on each date at Big Delta, in percent, and of at least 0.1 inch of snowfall.01020304050JanFebMarAprMayJunJulAugSepOctNovDec
  • Chance of a wet day
  • Chance of snowfall

Snow

NOAA 1991-2020 snowfall normals for Whitestone Farms.

41.5 in of snow in a normal year.

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Whitestone Farms. A median date has an even chance of a later freeze in spring, or an earlier one in fall.

The last spring freeze typically comes around May 26 and the first fall freeze around September 2, a growing season of about 98 days.

Median at 32°F
last May 26, first September 2
Median at 28°F
last May 15, first September 16

Frost dates, growing season and degree days

Humidity and comfort

NASA POWER reanalysis, 1991-2020, for the grid cell around Big Delta.

Days with a mean dew point of 65°F or more are rare here in every month.

MonthDew pointHumidityDryComfortableHumidMuggyOppressiveMiserable
January-2°F88%100%0%0%0%0%0%
February3°F87%100%0%0%0%0%0%
March7°F87%100%0%0%0%0%0%
April22°F75%100%0%0%0%0%0%
May32°F66%100%0%0%0%0%0%
June43°F68%98%2%0%0%0%0%
July47°F72%98%2%0%0%0%0%
August43°F74%99%1%0%0%0%0%
September34°F77%100%0%0%0%0%0%
October20°F85%100%0%0%0%0%0%
November6°F87%100%0%0%0%0%0%
December2°F88%100%0%0%0%0%0%

Comfort is judged by the day's mean dew point: dry below 55°F, comfortable to 60°F, humid to 65°F, muggy to 70°F, oppressive to 75°F, miserable above.

Clouds

Average share of the sky covered, from satellite (CERES and GEWEX SRB) by way of NASA POWER, 1991-2020.

The clearest month is March, with the sky 49 percent covered on average; the cloudiest is July, at 75 percent.

Wind

The mean wind speed over the whole day, from the MERRA-2 reanalysis by way of NASA POWER. Gusts run well above it.

The windiest month is December, averaging 7.8 mph at 10 meters (33 feet) above the ground.

Daylight and sunshine

The longest day is Jun 19, with 21 h 10 min of daylight; the shortest is Dec 18, with 4 h 07 min.

Hours of daylight at Big Delta through the year.0510152025JanFebMarAprMayJunJulAugSepOctNovDec
  • Day length

Solar energy

Average daily sunshine reaching the ground on a flat surface, in kilowatt-hours per square meter, clouds included.

Sunrise and sunset calendar

How Southeast Fairbanks Census Area is running

NOAA NCEI Climate at a Glance, from the nClimGrid analysis of every station, updated early each month. A rank of 1 is the highest or lowest of all years since 1895.

August 2026 in Southeast Fairbanks Census Area: 53.2°F (+3.3 °F against 1991-2020), the 8th warmest in 102 years on record.

August 2026 in Southeast Fairbanks Census Area: 2.75 in (-0.53 in against 1991-2020), the 45th driest in 102 years on record.

January to August 2026 in Southeast Fairbanks Census Area: 26.1°F (-3.5 °F against 1991-2020), the 17th coolest in 102 years on record.

January to August 2026 in Southeast Fairbanks Census Area: 15.06 in (+1.22 in against 1991-2020), the 21st wettest in 102 years on record.

Warmest August
55.9°F in 1994
Coolest August
42.9°F in 1969
Wettest August
7.21 in in 2018
Driest August
0.87 in in 2004

Every year since 1925

Each year's average temperature in Southeast Fairbanks Census Area against the 1991-2020 average, in °F, 1925 to 2025.-7.5-5-2.50+2.5+5+7.519401960198020002020NOAA NCEI Climate at a Glance

Alaska climate and rankings

Month pages

The weather in Big Delta in each month, day by day.

What this means

A normal is the average of the thirty years 1991 to 2020, the period the World Meteorological Organization and NOAA use for comparison. It is an average, not a forecast: most days depart from it, and some by a long way.

A record is the highest or lowest value on the date in every year the station has reported, back to 1917. It rests on one station, so a neighbor a few miles away can hold different ones.

Cloud, humidity, wind and sunshine come from a reanalysis: a weather model run over the past with every observation fed in, averaged over a grid cell about 50 km across. It is consistent everywhere on Earth; it smooths local detail such as a lake shore or a valley.

More for this place

Nearby

Sources

Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00509793 (Whitestone Farms), public domain. Records: NOAA GHCN-Daily, station USW00026415, every year on file, quality-flagged values removed. Cloud, humidity, wind and sunshine: NASA POWER (MERRA-2, CERES and GEWEX SRB), 1991-2020. The data was obtained from the National Aeronautics and Space Administration (NASA) Langley Research Center's Prediction Of Worldwide Energy Resources (POWER) project funded through the NASA Earth Science Division: POWER Daily API v2, accessed 2026-09-24. Sun and moon: computed with the NOAA solar equations and Meeus. Rankings: NOAA NCEI Climate at a Glance, public domain.