Portage Glacier V C, Alaska climate: Climate normals at a NOAA weather station
Portage Glacier V C's normal year runs from 16°F January nights to 62°F July afternoons, with 159.3 inches of precipitation a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 2.8°C, January lows of −9°C, July highs of 17°C, 4,046 mm of precipitation a year.
- NOAA stationPortage Glacier V C
- Station IDUSW00026492
- Location60.78°N 148.84°W
- Elevation103 ft (31 m)
On October 23, the normal high in Portage Glacier V C is 40°F and the normal low 29°F, and the chance of measurable rain or snow is 64%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Portage Glacier V C.
- Jan 28° 16°
- Feb 31° 19°
- Mar 34° 18°
- Apr 43° 29°
- May 52° 36°
- Jun 60° 43°
- Jul 62° 47°
- Aug 60° 45°
- Sep 54° 40°
- Oct 43° 31°
- Nov 33° 22°
- Dec 31° 18°
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 Portage Glacier V C each month?
July is the warmest month, with normal highs of 62°F; January the coldest, with normal lows of 16°F. The most precipitation falls in September (22.82 in), the least in July (7.24 in).
| Month | High | Low | Mean | Precip. | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|
| January | 28°F | 16°F | 21.6°F | 13.84 | 17 | <1 | 24 | 6 h 30 min |
| February | 31°F | 19°F | 24.9°F | 10.67 | 16 | <1 | 23 | 9 h |
| March | 34°F | 18°F | 25.7°F | 9.51 | 16 | <1 | 26 | 11 h 40 min |
| April | 43°F | 29°F | 35.7°F | 12.34 | 16 | <1 | 19 | 14 h 30 min |
| May | 52°F | 36°F | 43.9°F | 11.89 | 16 | <1 | 10 | 17 h 20 min |
| June | 60°F | 43°F | 51.1°F | 7.47 | 15 | <1 | 1 | 19 h 10 min |
| July | 62°F | 47°F | 54.4°F | 7.24 | 15 | <1 | <1 | 18 h 20 min |
| August | 60°F | 45°F | 52.4°F | 10.83 | 17 | <1 | <1 | 15 h 50 min |
| September | 54°F | 40°F | 46.6°F | 22.82 | 20 | <1 | 6 | 13 h |
| October | 43°F | 31°F | 37.0°F | 18.92 | 21 | <1 | 15 | 10 h 10 min |
| November | 33°F | 22°F | 27.5°F | 16.28 | 18 | <1 | 23 | 7 h 30 min |
| December | 31°F | 18°F | 24.5°F | 17.49 | 19 | <1 | 24 | 5 h 40 min |
| Year (annual) | 44°F | 30°F | 37.1°F | 159.30 | 204 | <1 | 171 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. |
|---|---|---|---|---|
| January | −2°C | −9°C | −5.8°C | 352 mm |
| February | −1°C | −7°C | −3.9°C | 271 mm |
| March | 1°C | −8°C | −3.5°C | 242 mm |
| April | 6°C | −2°C | 2.1°C | 313 mm |
| May | 11°C | 2°C | 6.6°C | 302 mm |
| June | 15°C | 6°C | 10.6°C | 190 mm |
| July | 17°C | 8°C | 12.4°C | 184 mm |
| August | 16°C | 7°C | 11.3°C | 275 mm |
| September | 12°C | 4°C | 8.1°C | 580 mm |
| October | 6°C | 0°C | 2.8°C | 481 mm |
| November | 0°C | −5°C | −2.5°C | 414 mm |
| December | −1°C | −8°C | −4.2°C | 444 mm |
NOAA publishes no 1991-2020 snowfall normal for this station. The nearest record that keeps one, Whittier (5 miles away), gets 268 inches of snow in a normal year; elevation and distance can change that.
Source: NOAA NCEI 1991-2020 monthly normals, station USW00026492; 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 Portage Glacier V C?
No month's normal high reaches 65°F in Portage Glacier V C: the warmest is July at 62°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 USW00026492.
When is the last frost at Portage Glacier V C?
In Portage Glacier V C, the last spring frost (32°F) comes after May 27 in half of years and after June 11 in one year in ten; the first autumn frost comes before September 12 in half of years and before August 24 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 271 year in 10 after June 11; 9 in 10 after May 12
- First autumn frost, half of years before
- September 121 year in 10 before August 24; 9 in 10 before September 30
NOAA puts the median frost-free season at 106 days, and the season without a hard freeze (28°F) at 145 days.
A hard freeze (28°F) comes after May 4 in half of springs and before October 1 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Portage Glacier V C in zone 5b in ZIP code 99587, 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 5a: the coldest night of a typical year reaches −19°F (19 complete years); the map interpolates between stations and terrain, so the station and the ZIP area can differ by half a zone.
Frost dates for every NOAA station in Alaska · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USW00026492; 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 Portage Glacier V C?
In a normal year in Portage Glacier V C, a 90°F day is rare, 171 nights fall to 32°F or colder and 204 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
- 171a normal year
- Days that stay below freezing
- 67high of 32°F or less
- Days with 0.01 inch of precipitation
- 204a normal year
Source: NOAA NCEI 1991-2020 annual normals, station USW00026492.
How sunny is it at Portage Glacier V C?
Over a year 59% of the sunlight that would reach the ground under clear skies gets through the clouds at Portage Glacier V C, 2.4 kWh per square metre a day. March is the sunniest month (64%) and November the cloudiest (52%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 53% | 0.3 |
| February | 55% | 0.9 |
| March | 64% | 2.3 |
| April | 61% | 3.6 |
| May | 61% | 4.6 |
| June | 59% | 4.9 |
| July | 60% | 4.6 |
| August | 58% | 3.5 |
| September | 57% | 2.3 |
| October | 53% | 1.1 |
| November | 52% | 0.4 |
| December | 53% | 0.2 |
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 Portage Glacier V C record?
A normal year at Portage Glacier V C brings 10,152 heating degree days, 89% more than 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 314 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,345 | 0 |
| February | 1,123 | 0 |
| March | 1,217 | 0 |
| April | 879 | 0 |
| May | 654 | 0 |
| June | 417 | 0 |
| July | 329 | 0 |
| August | 389 | 0 |
| September | 552 | 0 |
| October | 866 | 0 |
| November | 1,123 | 0 |
| December | 1,257 | 0 |
| Year (annual) | 10,152 | 1 |
Source: NOAA NCEI 1991-2020 monthly normals, station USW00026492. 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 Portage Glacier V C been warmer than normal?
2025 averaged 38.6°F, 1.5°F above the 1991-2020 normal of 37.1°F.
| Year | Mean | Against normal | Precip. |
|---|---|---|---|
| 2025 | 38.6°F | +1.5°F | – |
Source: observed years: ACIS, station USW00026492. A year counts only with all twelve months complete.
How does Portage Glacier V C's climate compare?
Portage Glacier V C is warmer than 53 of the 85 places with their own NOAA record in Alaska, and wetter than 71. Across the 7,247 U.S. stations with normals, its annual mean of 37.1°F is warmer than 3%.
In the Köppen classification computed from these normals, Portage Glacier V C is Dfc: continental, no dry season, 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 Portage Glacier V C's climate
What is the coldest month at Portage Glacier V C?
January, with a normal high of 28°F and a normal low of 16°F. The warmest is July (62°F by day, 47°F at night).
Does it snow at Portage Glacier V C?
Yes. NOAA publishes no 1991-2020 snowfall normal for the station; the nearest record that keeps one, Whittier (5 miles away), records 268 inches of snow in a normal year.
What is the rainiest month at Portage Glacier V C?
September, with 22.82 in of precipitation in a normal year; the driest is July with 7.24 in.
What plant hardiness zone is Portage Glacier V C in?
The USDA's 2023 map puts Portage Glacier V C in zone 5b in ZIP code 99587, the nearest ZIP area. By the same method at the station, the coldest night of a typical year reaches −19°F (19 years, 1991-2020): zone 5a.
How late can frost come at Portage Glacier V C?
In half of years the last 32°F night comes after May 27; in one year in ten it comes after June 11. Waiting until June 11 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Alaska climateThe statewide normals and every place in the state
- Whittier, AK5 miles from this station, 41.1°F a year
- Alyeska, AK15 miles from this station, 38.7°F a year
- Wally Noerenberg Hatchery, AK25 miles from this station, 40.0°F a year
- Hope, AK28 miles from this station, 36.5°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made