Glen Alps, Alaska climate: Climate normals at a NOAA weather station
Glen Alps's normal year runs from 14°F January nights to 59°F July afternoons, with 26.0 inches of precipitation and 162 inches of snow a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 1.4°C, January lows of −10°C, July highs of 15°C, 661 mm of precipitation a year.
- NOAA stationGlen Alps
- Station IDUSC00503299
- Location61.10°N 149.69°W
- Elevation2,202 ft (671 m)
On October 23, the normal high in Glen Alps is 35°F and the normal low 25°F, and the chance of measurable rain or snow is 49%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Glen Alps.
- Jan 26° 14°
- Feb 27° 16°
- Mar 29° 16°
- Apr 38° 27°
- May 49° 36°
- Jun 57° 43°
- Jul 59° 47°
- Aug 57° 46°
- Sep 49° 38°
- Oct 38° 28°
- Nov 29° 18°
- Dec 27° 16°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
What is the weather like at Glen Alps each month?
July is the warmest month, with normal highs of 59°F; January the coldest, with normal lows of 14°F. The most precipitation falls in September (4.34 in), the least in May (0.85 in).
| Month | High | Low | Mean | Precip. | Snow | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|---|
| January | 26°F | 14°F | 19.9°F | 1.65 | 19.5 | 12 | <1 | 30 | 6 h 20 min |
| February | 27°F | 16°F | 21.6°F | 1.74 | 21.5 | 13 | <1 | 27 | 9 h |
| March | 29°F | 16°F | 22.4°F | 1.76 | 27.5 | 13 | <1 | 31 | 11 h 40 min |
| April | 38°F | 27°F | 32.2°F | 1.18 | 11.7 | 11 | <1 | 26 | 14 h 40 min |
| May | 49°F | 36°F | 42.2°F | 0.85 | 3.3 | 10 | <1 | 11 | 17 h 20 min |
| June | 57°F | 43°F | 49.9°F | 1.23 | 0.0 | 11 | <1 | <1 | 19 h 10 min |
| July | 59°F | 47°F | 53.3°F | 2.33 | 0.0 | 15 | <1 | <1 | 18 h 30 min |
| August | 57°F | 46°F | 51.6°F | 3.55 | 0.0 | 16 | <1 | <1 | 16 h |
| September | 49°F | 38°F | 43.7°F | 4.34 | 2.5 | 18 | <1 | 6 | 13 h |
| October | 38°F | 28°F | 32.7°F | 2.65 | 14.4 | 16 | <1 | 23 | 10 h 10 min |
| November | 29°F | 18°F | 23.6°F | 2.10 | 23.9 | 14 | <1 | 28 | 7 h 20 min |
| December | 27°F | 16°F | 21.5°F | 2.64 | 37.6 | 15 | <1 | 30 | 5 h 40 min |
| Year (annual) | 40°F | 29°F | 34.5°F | 26.02 | 161.9 | 162 | <1 | 212 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. | Snow |
|---|---|---|---|---|---|
| January | −4°C | −10°C | −6.7°C | 42 mm | 50 cm |
| February | −3°C | −9°C | −5.8°C | 44 mm | 55 cm |
| March | −2°C | −9°C | −5.3°C | 45 mm | 70 cm |
| April | 3°C | −3°C | 0.1°C | 30 mm | 30 cm |
| May | 9°C | 2°C | 5.7°C | 22 mm | 8 cm |
| June | 14°C | 6°C | 9.9°C | 31 mm | 0 cm |
| July | 15°C | 9°C | 11.8°C | 59 mm | 0 cm |
| August | 14°C | 8°C | 10.9°C | 90 mm | 0 cm |
| September | 10°C | 3°C | 6.5°C | 110 mm | 6 cm |
| October | 3°C | −2°C | 0.4°C | 67 mm | 37 cm |
| November | −2°C | −8°C | −4.7°C | 53 mm | 61 cm |
| December | −3°C | −9°C | −5.8°C | 67 mm | 96 cm |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00503299; 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.
Which months are mildest at Glen Alps?
No month's normal high reaches 65°F in Glen Alps: the warmest is July at 59°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 USC00503299.
When is the last frost at Glen Alps?
In Glen Alps, the last spring frost (32°F) comes after May 18 in half of years and after May 31 in one year in ten; the first autumn frost comes before September 23 in half of years and before September 8 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 181 year in 10 after May 31; 9 in 10 after May 4
- First autumn frost, half of years before
- September 231 year in 10 before September 8; 9 in 10 before October 6
NOAA puts the median frost-free season at 125 days, and the season without a hard freeze (28°F) at 151 days.
A hard freeze (28°F) comes after May 4 in half of springs and before October 2 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Glen Alps in zone 5b in ZIP code 99516, the nearest ZIP area. By the map's own method, the average of each year's coldest night over 1991-2020, the station is in zone 5b: the coldest night of a typical year reaches −14°F (23 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 USC00503299; 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 at Glen Alps?
In a normal year in Glen Alps, a 90°F day is rare, 212 nights fall to 32°F or colder and 162 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
- 212a normal year
- Days that stay below freezing
- 104high of 32°F or less
- Days with 0.01 inch of precipitation
- 162a normal year
- Days with 1 inch of snow or more
- 54a normal year
The highest temperature in this station's record (since 1971) is 78°F, on June 18, 2013; the lowest is −37°F, on January 28, 1989.
The wettest calendar year on that record is 2013, with 37.38 in; the snowiest season is 1994–95, with 249.0 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USC00503299; records: ACIS (NOAA Regional Climate Centers), station USC00503299. Records use complete months only; a month missing more than three days is left out.
How sunny is it at Glen Alps?
Over a year 64% of the sunlight that would reach the ground under clear skies gets through the clouds at Glen Alps, 2.5 kWh per square metre a day. April is the sunniest month (70%) and October the cloudiest (55%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 57% | 0.3 |
| February | 59% | 0.9 |
| March | 68% | 2.4 |
| April | 70% | 4.0 |
| May | 66% | 5.0 |
| June | 65% | 5.3 |
| July | 63% | 4.8 |
| August | 63% | 3.8 |
| September | 61% | 2.4 |
| October | 55% | 1.1 |
| November | 55% | 0.4 |
| December | 56% | 0.1 |
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 many heating and cooling degree days does Glen Alps record?
A normal year at Glen Alps brings 11,088 heating degree days, 2.1 times the median U.S. place (5,373), and 1 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 281 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,400 | 0 |
| February | 1,214 | 0 |
| March | 1,321 | 0 |
| April | 984 | 0 |
| May | 707 | 0 |
| June | 452 | 0 |
| July | 362 | 1 |
| August | 417 | 0 |
| September | 639 | 0 |
| October | 1,001 | 0 |
| November | 1,242 | 0 |
| December | 1,350 | 0 |
| Year (annual) | 11,088 | 1 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00503299. 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.
Have recent years at Glen Alps been warmer than normal?
Over 30 complete years from 1978 to 2015, the station's annual mean temperature rose at a fitted 1.3°F per century (+0.07°C per decade). A fitted rate summarizes the whole record; single years swing well above and below it.
Source: trend: NOAA GHCN-Monthly v4. A year counts only with all twelve months complete.
How does Glen Alps's climate compare?
Glen Alps is warmer than 40 of the 85 places with their own NOAA record in Alaska, and wetter than 47. Across the 7,247 U.S. stations with normals, its annual mean of 34.5°F is warmer than 1%.
In the Köppen classification computed from these normals, Glen Alps is Dsc: continental, dry-summer, cool summer. 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 Glen Alps's climate
What is the coldest month at Glen Alps?
January, with a normal high of 26°F and a normal low of 14°F. The warmest is July (59°F by day, 47°F at night).
Does it snow at Glen Alps?
Yes: 162 inches in a normal year, falling on 54 days with 0.1 inch or more, the most in December (37.6 inches).
What is the rainiest month at Glen Alps?
September, with 4.34 in of precipitation in a normal year; the driest is May with 0.85 in.
What plant hardiness zone is Glen Alps in?
The USDA's 2023 map puts Glen Alps in zone 5b in ZIP code 99516, the nearest ZIP area. By the same method at the station, the coldest night of a typical year reaches −14°F (23 years, 1991-2020): zone 5b.
How late can frost come at Glen Alps?
In half of years the last 32°F night comes after May 18; in one year in ten it comes after May 31. Waiting until May 31 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Alaska climateThe statewide normals and every place in the state
- Anchorage Rabbit Creek #2, AK2 miles from this station, 36.5°F a year
- Campbell Creek Science Center, AK5 miles from this station, 34.1°F a year
- Fort Richardson Water Treatment Plant, AK9 miles from this station, 36.1°F a year
- Anchorage Lake Hood Airport, AK11 miles from this station, 38.0°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made