St. George, Alaska climate: Normal weather by month, frost dates and records
St. George's normal year runs from 23°F January nights to 52°F August afternoons, with 20.4 inches of precipitation a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 2.6°C, January lows of −5°C, August highs of 11°C, 518 mm of precipitation a year.
- NOAA stationSt George Island Airport
- Station IDUSW00025628
- Location56.60°N 169.56°W
- Elevation125 ft (38 m)
- Population68
On October 14, the normal high in St. George is 44°F and the normal low 36°F, and the chance of measurable rain or snow is 74%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for St. George.
- Jan 30° 23°
- Feb 32° 24°
- Mar 31° 23°
- Apr 35° 28°
- May 42° 34°
- Jun 47° 39°
- Jul 51° 44°
- Aug 52° 46°
- Sep 50° 42°
- Oct 43° 36°
- Nov 38° 30°
- Dec 34° 26°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
What is the weather like in St. George each month?
August is the warmest month, with normal highs of 52°F; January the coldest, with normal lows of 23°F. The most precipitation falls in October (3.00 in), the least in March (0.80 in).
| Month | High | Low | Mean | Precip. | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|
| January | 30°F | 23°F | 26.5°F | 1.17 | 13 | <1 | 26 | 7 h 30 min |
| February | 32°F | 24°F | 27.7°F | 1.06 | 14 | <1 | 22 | 9 h 30 min |
| March | 31°F | 23°F | 27.3°F | 0.80 | 11 | <1 | 27 | 11 h 40 min |
| April | 35°F | 28°F | 31.5°F | 0.89 | 11 | <1 | 23 | 14 h 10 min |
| May | 42°F | 34°F | 37.6°F | 1.01 | 13 | <1 | 12 | 16 h 20 min |
| June | 47°F | 39°F | 43.3°F | 1.26 | 12 | <1 | 1 | 17 h 40 min |
| July | 51°F | 44°F | 47.8°F | 1.97 | 14 | <1 | <1 | 17 h 10 min |
| August | 52°F | 46°F | 49.3°F | 2.66 | 18 | <1 | <1 | 15 h 20 min |
| September | 50°F | 42°F | 46.0°F | 2.53 | 20 | <1 | 1 | 12 h 50 min |
| October | 43°F | 36°F | 39.5°F | 3.00 | 23 | <1 | 8 | 10 h 30 min |
| November | 38°F | 30°F | 34.1°F | 2.25 | 21 | <1 | 17 | 8 h 10 min |
| December | 34°F | 26°F | 29.8°F | 1.78 | 19 | <1 | 24 | 6 h 50 min |
| Year (annual) | 41°F | 33°F | 36.7°F | 20.38 | 188 | <1 | 162 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. |
|---|---|---|---|---|
| January | −1°C | −5°C | −3.1°C | 30 mm |
| February | 0°C | −4°C | −2.4°C | 27 mm |
| March | 0°C | −5°C | −2.6°C | 20 mm |
| April | 2°C | −2°C | −0.3°C | 23 mm |
| May | 5°C | 1°C | 3.1°C | 26 mm |
| June | 8°C | 4°C | 6.3°C | 32 mm |
| July | 11°C | 7°C | 8.8°C | 50 mm |
| August | 11°C | 8°C | 9.6°C | 68 mm |
| September | 10°C | 6°C | 7.8°C | 64 mm |
| October | 6°C | 2°C | 4.2°C | 76 mm |
| November | 3°C | −1°C | 1.2°C | 57 mm |
| December | 1°C | −3°C | −1.2°C | 45 mm |
NOAA publishes no 1991-2020 snowfall normal for this station, and no record within 25 miles keeps one, so snow is left out here rather than estimated.
Source: NOAA NCEI 1991-2020 monthly normals, station USW00025628; annual normals. Wet days: 0.01 inch or more; 90°F days and freezing nights: NOAA's day counts. Daylight: sunrise to sunset on the 15th, computed from the latitude.
When is the best weather to visit St. George?
No month's normal high reaches 65°F in St. George: the warmest is August at 52°F.
That is a measurement, not a recommendation: it counts the months whose normal afternoon high sits between 65°F and 85°F, where a light layer is enough by day.
Source: NOAA NCEI 1991-2020 monthly normals, station USW00025628.
When is the last frost in St. George?
In St. George, the last spring frost (32°F) comes after May 31 in half of years and after June 23 in one year in ten; the first autumn frost comes before October 5 in half of years and before September 17 in one year in ten.
Frost-free in half of yearsFrost in 1 to 9 years out of 10Frost most years
- Last spring frost, half of years after
- May 311 year in 10 after June 23; 9 in 10 after May 10
- First autumn frost, half of years before
- October 51 year in 10 before September 17; 9 in 10 before October 21
NOAA puts the median frost-free season at 128 days, and the season without a hard freeze (28°F) at 166 days.
A hard freeze (28°F) comes after May 9 in half of springs and before October 24 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts St. George in zone 7a in ZIP code 99591. By the map's own method, the average of each year's coldest night over 1991-2020, St. George's NOAA station is in zone 7a: the coldest night of a typical year reaches 4°F (18 complete years).
Frost dates for every NOAA station in Alaska · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USW00025628; USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026; the station zone: ACIS daily lows, 1991-2020. A 10% date means one year in ten has a frost after it in spring or before it in autumn.
How hot and how cold does it get in St. George?
In a normal year in St. George, a 90°F day is rare, 162 nights fall to 32°F or colder and 188 days bring measurable precipitation.
- Days at 90°F or more
- fewer than 1a normal year
- Days at 100°F or more
- fewer than 1a normal year
- Nights at 32°F or colder
- 162a normal year
- Days that stay below freezing
- 64high of 32°F or less
- Days with 0.01 inch of precipitation
- 188a normal year
Source: NOAA NCEI 1991-2020 annual normals, station USW00025628.
How sunny is St. George?
Over a year 54% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around St. George, 2.3 kWh per square metre a day. March is the sunniest month (58%) and January the cloudiest (49%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 49% | 0.5 |
| February | 52% | 1.0 |
| March | 58% | 2.3 |
| April | 57% | 3.4 |
| May | 57% | 4.2 |
| June | 53% | 4.3 |
| July | 51% | 3.8 |
| August | 52% | 3.2 |
| September | 55% | 2.4 |
| October | 57% | 1.4 |
| November | 50% | 0.6 |
| December | 50% | 0.3 |
Source: NASA POWER solar climatology, 2001-2020 (CERES SYN1deg). Satellite-based, for the 1-degree cell (about 100 km across) around the station, so it describes the area rather than the airport.
How much heating and cooling does St. George need?
A normal year in St. George brings 10,305 heating degree days, 92% more than the median U.S. place (5,373), and 0 cooling degree days, 100% fewer than the median (908). Twelve months need 300 or more heating degree days, a monthly mean of about 55°F or colder. For gardens and crops, NOAA counts 40 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,192 | 0 |
| February | 1,043 | 0 |
| March | 1,167 | 0 |
| April | 1,005 | 0 |
| May | 849 | 0 |
| June | 651 | 0 |
| July | 533 | 0 |
| August | 487 | 0 |
| September | 570 | 0 |
| October | 791 | 0 |
| November | 926 | 0 |
| December | 1,091 | 0 |
| Year (annual) | 10,305 | 0 |
Source: NOAA NCEI 1991-2020 monthly normals, station USW00025628. A degree day is one degree of a day's mean temperature below 65°F (heating) or above it (cooling); utilities use them to estimate energy use.
How does St. George's climate compare?
St. George is warmer than 50 of the other 84 places with their own NOAA record in Alaska, and wetter than 37. Across the 7,247 U.S. stations with normals, its annual mean of 36.7°F is warmer than 2%.
In the Köppen classification computed from these normals, St. George is ET: tundra. What the classes mean.
Places with the most similar year elsewhere
Measured month by month on the normal high, low and precipitation, among places of 20,000 or more people in other states:
Source: NOAA NCEI 1991-2020 normals for every station PlainClimate covers. Similarity: the root-mean-square difference of the 36 monthly figures, precipitation weighted so an inch counts like 6°F.
Questions about St. George's climate
What is the coldest month in St. George?
January, with a normal high of 30°F and a normal low of 23°F. The warmest is August (52°F by day, 46°F at night).
What is the rainiest month in St. George?
October, with 3.00 in of precipitation in a normal year; the driest is March with 0.80 in.
What plant hardiness zone is St. George in?
The USDA's 2023 map puts St. George in zone 7a in ZIP code 99591. By the same method at St. George's NOAA station, the coldest night of a typical year reaches 4°F (18 years, 1991-2020): zone 7a.
How late can frost come in St. George?
In half of years the last 32°F night comes after May 31; in one year in ten it comes after June 23. Waiting until June 23 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Alaska climateThe statewide normals and every place in the state
- St. Paul, AK46 miles from this station, 35.9°F a year
- Dutch Harbor, AK222 miles from this station, 41.6°F a year
- Cold Bay, AK281 miles from this station, 39.3°F a year
- Sand Point, AK362 miles from this station, 39.9°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made