Whittier, Alaska climate: Normal weather by month, frost dates and records
Whittier's normal year runs from 24°F January nights to 63°F July afternoons, with 197.3 inches of precipitation and 268 inches of snow a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 5.1°C, January lows of −5°C, July highs of 17°C, 5,012 mm of precipitation a year.
- NOAA stationWhittier
- Station IDUSC00509829
- Location60.78°N 148.69°W
- Elevation60 ft (18 m)
- Population253
On October 24, the normal high in Whittier is 42°F and the normal low 34°F, and the chance of measurable rain or snow is 61%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Whittier.
- Jan 33° 24°
- Feb 33° 25°
- Mar 36° 27°
- Apr 44° 33°
- May 53° 41°
- Jun 61° 47°
- Jul 63° 51°
- Aug 62° 51°
- Sep 54° 45°
- Oct 44° 36°
- Nov 37° 29°
- Dec 34° 25°
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 Whittier each month?
July is the warmest month, with normal highs of 63°F; January the coldest, with normal lows of 24°F. The most precipitation falls in September (22.52 in), the least in June (9.21 in).
| Month | High | Low | Mean | Precip. | Snow | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|---|
| January | 33°F | 24°F | 28.2°F | 18.82 | 50.0 | 18 | <1 | 24 | 6 h 30 min |
| February | 33°F | 25°F | 29.2°F | 16.15 | 44.8 | 17 | <1 | 21 | 9 h |
| March | 36°F | 27°F | 31.2°F | 13.65 | 55.1 | 16 | <1 | 22 | 11 h 40 min |
| April | 44°F | 33°F | 38.6°F | 14.71 | 15.9 | 16 | <1 | 9 | 14 h 30 min |
| May | 53°F | 41°F | 46.8°F | 14.93 | 1.8 | 15 | <1 | <1 | 17 h 20 min |
| June | 61°F | 47°F | 54.1°F | 9.21 | 0.0 | 15 | <1 | <1 | 19 h 10 min |
| July | 63°F | 51°F | 57.2°F | 11.19 | 0.0 | 18 | <1 | <1 | 18 h 20 min |
| August | 62°F | 51°F | 56.1°F | 16.52 | 0.0 | 17 | <1 | <1 | 15 h 50 min |
| September | 54°F | 45°F | 49.5°F | 22.52 | 0.0 | 18 | <1 | <1 | 13 h |
| October | 44°F | 36°F | 40.1°F | 21.05 | 5.9 | 20 | <1 | 7 | 10 h 10 min |
| November | 37°F | 29°F | 32.5°F | 18.75 | 33.3 | 18 | <1 | 20 | 7 h 30 min |
| December | 34°F | 25°F | 29.6°F | 19.81 | 61.4 | 20 | <1 | 24 | 5 h 40 min |
| Year (annual) | 46°F | 36°F | 41.1°F | 197.31 | 268.2 | 208 | <1 | 127 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. | Snow |
|---|---|---|---|---|---|
| January | 0°C | −5°C | −2.1°C | 478 mm | 127 cm |
| February | 1°C | −4°C | −1.6°C | 410 mm | 114 cm |
| March | 2°C | −3°C | −0.4°C | 347 mm | 140 cm |
| April | 7°C | 1°C | 3.7°C | 374 mm | 40 cm |
| May | 12°C | 5°C | 8.2°C | 379 mm | 5 cm |
| June | 16°C | 8°C | 12.3°C | 234 mm | 0 cm |
| July | 17°C | 11°C | 14.0°C | 284 mm | 0 cm |
| August | 16°C | 10°C | 13.4°C | 420 mm | 0 cm |
| September | 12°C | 7°C | 9.7°C | 572 mm | 0 cm |
| October | 7°C | 2°C | 4.5°C | 535 mm | 15 cm |
| November | 3°C | −2°C | 0.3°C | 476 mm | 85 cm |
| December | 1°C | −4°C | −1.3°C | 503 mm | 156 cm |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00509829; 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 Whittier?
No month's normal high reaches 65°F in Whittier: the warmest is July at 63°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 USC00509829.
When is the last frost in Whittier?
In Whittier, the last spring frost (32°F) comes after April 25 in half of years and after May 8 in one year in ten; the first autumn frost comes before October 14 in half of years and before October 1 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
- April 251 year in 10 after May 8; 9 in 10 after April 12
- First autumn frost, half of years before
- October 141 year in 10 before October 1; 9 in 10 before October 30
NOAA puts the median frost-free season at 172 days, and the season without a hard freeze (28°F) at 198 days.
A hard freeze (28°F) comes after April 11 in half of springs and before October 26 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Whittier in zone 7a in ZIP code 99693.
Frost dates for every NOAA station in Alaska · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USC00509829; USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026. 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 Whittier?
In a normal year in Whittier, a 90°F day is rare, 127 nights fall to 32°F or colder and 208 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
- 127a normal year
- Days that stay below freezing
- 47high of 32°F or less
- Days with 0.01 inch of precipitation
- 208a normal year
- Days with 1 inch of snow or more
- 51a normal year
The highest temperature in this station's record (since 1942) is 87°F, on August 9, 1957; the lowest is −19°F, on December 17, 1957.
The wettest calendar year on that record is 1987, with 317.49 in; the snowiest season is 1998–99, with 400.8 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USC00509829; records: ACIS (NOAA Regional Climate Centers), station USC00509829. Records use complete months only; a month missing more than three days is left out.
How sunny is Whittier?
Over a year 59% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Whittier, 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 much heating and cooling does Whittier need?
A normal year in Whittier brings 8,708 heating degree days, 62% more than the median U.S. place (5,373), and 9 cooling degree days, 99% fewer than the median (908). Ten months need 300 or more heating degree days, a monthly mean of about 55°F or colder. For gardens and crops, NOAA counts 628 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,139 | 0 |
| February | 1,001 | 0 |
| March | 1,046 | 0 |
| April | 794 | 0 |
| May | 563 | 0 |
| June | 329 | 1 |
| July | 246 | 5 |
| August | 278 | 2 |
| September | 467 | 0 |
| October | 773 | 0 |
| November | 975 | 0 |
| December | 1,099 | 0 |
| Year (annual) | 8,708 | 9 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00509829. 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 Whittier's climate compare?
Whittier is warmer than 65 of the other 84 places with their own NOAA record in Alaska, and wetter than 73. Across the 7,247 U.S. stations with normals, its annual mean of 41.1°F is warmer than 8%.
In the Köppen classification computed from these normals, Whittier 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 Whittier's climate
What is the coldest month in Whittier?
January, with a normal high of 33°F and a normal low of 24°F. The warmest is July (63°F by day, 51°F at night).
Does it snow in Whittier?
Yes: 268 inches in a normal year, falling on 59 days with 0.1 inch or more, the most in December (61.4 inches).
What is the rainiest month in Whittier?
September, with 22.52 in of precipitation in a normal year; the driest is June with 9.21 in.
What plant hardiness zone is Whittier in?
The USDA's 2023 map puts Whittier in zone 7a in ZIP code 99693.
How late can frost come in Whittier?
In half of years the last 32°F night comes after April 25; in one year in ten it comes after May 8. Waiting until May 8 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Alaska climateThe statewide normals and every place in the state
- Portage Glacier V C, AK5 miles from this station, 37.1°F a year
- Alyeska, AK19 miles from this station, 38.7°F a year
- Wally Noerenberg Hatchery, AK21 miles from this station, 40.0°F a year
- Main Bay, AK27 miles from this station, 39.5°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made