Omak, Washington climate: Normal weather by month, frost dates and records
Omak's normal year runs from 23°F December nights to 89°F July afternoons, with 11.6 inches of precipitation a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 9.9°C, December lows of −5°C, July highs of 32°C, 295 mm of precipitation a year.
- NOAA stationOmak
- Station IDUSW00094197
- Location48.46°N 119.52°W
- Elevation1,296 ft (395 m)
- Population5,167
On October 23, the normal high in Omak is 56°F and the normal low 35°F, and the chance of measurable rain or snow is 22%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Omak.
- Jan 33° 23°
- Feb 40° 25°
- Mar 53° 31°
- Apr 63° 37°
- May 72° 45°
- Jun 79° 51°
- Jul 89° 58°
- Aug 89° 57°
- Sep 78° 48°
- Oct 61° 38°
- Nov 43° 29°
- Dec 33° 23°
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 Omak each month?
July is the warmest month, with normal highs of 89°F; December the coldest, with normal lows of 23°F. The most precipitation falls in December (1.95 in), the least in August (0.27 in).
| Month | High | Low | Mean | Precip. | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|
| January | 33°F | 23°F | 28.0°F | 1.33 | 10 | <1 | 28 | 8 h 40 min |
| February | 40°F | 25°F | 32.5°F | 0.91 | 8 | <1 | 24 | 10 h 10 min |
| March | 53°F | 31°F | 41.8°F | 1.06 | 8 | <1 | 20 | 11 h 50 min |
| April | 63°F | 37°F | 49.8°F | 0.83 | 6 | <1 | 11 | 13 h 40 min |
| May | 72°F | 45°F | 58.8°F | 1.19 | 8 | 1 | 2 | 15 h 10 min |
| June | 79°F | 51°F | 65.1°F | 0.98 | 7 | 4 | <1 | 16 h 10 min |
| July | 89°F | 58°F | 73.7°F | 0.52 | 3 | 17 | <1 | 15 h 50 min |
| August | 89°F | 57°F | 72.8°F | 0.27 | 2 | 16 | <1 | 14 h 20 min |
| September | 78°F | 48°F | 63.3°F | 0.40 | 4 | 3 | 1 | 12 h 40 min |
| October | 61°F | 38°F | 49.1°F | 0.92 | 6 | <1 | 10 | 11 h |
| November | 43°F | 29°F | 35.9°F | 1.24 | 9 | <1 | 20 | 9 h 20 min |
| December | 33°F | 23°F | 27.9°F | 1.95 | 12 | <1 | 28 | 8 h 20 min |
| Year (annual) | 61°F | 39°F | 49.9°F | 11.60 | 82 | 42 | 145 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. |
|---|---|---|---|---|
| January | 0°C | −5°C | −2.2°C | 34 mm |
| February | 4°C | −4°C | 0.3°C | 23 mm |
| March | 11°C | 0°C | 5.4°C | 27 mm |
| April | 17°C | 3°C | 9.9°C | 21 mm |
| May | 22°C | 7°C | 14.9°C | 30 mm |
| June | 26°C | 11°C | 18.4°C | 25 mm |
| July | 32°C | 15°C | 23.2°C | 13 mm |
| August | 32°C | 14°C | 22.7°C | 7 mm |
| September | 26°C | 9°C | 17.4°C | 10 mm |
| October | 16°C | 3°C | 9.5°C | 23 mm |
| November | 6°C | −2°C | 2.2°C | 31 mm |
| December | 0°C | −5°C | −2.3°C | 50 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 USW00094197; 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 Omak?
Normal highs sit between 65°F and 85°F in May, June and September. Of those, September has the fewest days with rain (4).
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 USW00094197.
When is the last frost in Omak?
In Omak, the last spring frost (32°F) comes after April 30 in half of years and after May 15 in one year in ten; the first autumn frost comes before October 7 in half of years and before September 23 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 301 year in 10 after May 15; 9 in 10 after April 14
- First autumn frost, half of years before
- October 71 year in 10 before September 23; 9 in 10 before October 22
NOAA puts the median frost-free season at 160 days, and the season without a hard freeze (28°F) at 188 days.
A hard freeze (28°F) comes after April 14 in half of springs and before October 19 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Omak in zone 7a in ZIP code 98840, the nearest ZIP area. By the map's own method, the average of each year's coldest night over 1991-2020, Omak's NOAA station is in zone 6b: the coldest night of a typical year reaches −1°F (21 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 Washington · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USW00094197; 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 Omak?
In a normal year in Omak, 42 days a year reach 90°F (6 of them 100°F or more), 145 nights fall to 32°F or colder and 82 days bring measurable precipitation.
- Days at 90°F or more
- 42a normal year
- Days at 100°F or more
- 6a normal year
- Nights at 32°F or colder
- 145a normal year
- Days that stay below freezing
- 35high of 32°F or less
- Days with 0.01 inch of precipitation
- 82a normal year
The highest temperature in Omak's official record (kept by the National Weather Service since 1909) is 117°F, on June 29, 2021; the lowest is −26°F, on February 1, 1950.
The wettest calendar year on that record is 1941, with 20.85 in; the snowiest season is 1937–38, with 56.0 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USW00094197; records: ACIS (NOAA Regional Climate Centers), NWS threaded record OMKthr. Records use complete months only; a month missing more than three days is left out.
How sunny is Omak?
Over a year 75% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Omak, 3.9 kWh per square metre a day. July is the sunniest month (88%) and December the cloudiest (54%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 57% | 1.1 |
| February | 68% | 2.2 |
| March | 68% | 3.3 |
| April | 71% | 4.8 |
| May | 74% | 5.9 |
| June | 75% | 6.4 |
| July | 88% | 7.2 |
| August | 87% | 6.0 |
| September | 82% | 4.4 |
| October | 73% | 2.6 |
| November | 59% | 1.3 |
| December | 54% | 0.9 |
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 Omak need?
A normal year in Omak brings 6,177 heating degree days, 15% more than the median U.S. place (5,373), and 703 cooling degree days, 23% fewer than the median (908). Seven months need 300 or more heating degree days, a monthly mean of about 55°F or colder. For gardens and crops, NOAA counts 2,743 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,145 | 0 |
| February | 910 | 0 |
| March | 719 | 0 |
| April | 457 | 1 |
| May | 214 | 20 |
| June | 78 | 81 |
| July | 10 | 281 |
| August | 11 | 253 |
| September | 117 | 66 |
| October | 495 | 2 |
| November | 872 | 0 |
| December | 1,150 | 0 |
| Year (annual) | 6,177 | 703 |
Source: NOAA NCEI 1991-2020 monthly normals, station USW00094197. 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.
Has Omak been warmer than normal lately?
2025 averaged 51.8°F, 1.9°F above the 1991-2020 normal of 49.9°F. 4 of the 5 complete years since 2021 ran warmer than the normal.
| Year | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 52.1°F | +2.2°F | 9.90 |
| 2022 | 48.8°F | −1.1°F | 13.13 |
| 2023 | 51.8°F | +1.9°F | 10.77 |
| 2024 | 52.0°F | +2.1°F | 13.75 |
| 2025 | 51.8°F | +1.9°F | 8.72 |
Source: observed years: ACIS, station USW00094197. A year counts only with all twelve months complete.
How does Omak's climate compare?
Omak is warmer than 37 of the other 95 places with their own NOAA record in Washington, and wetter than 20. Across the 7,247 U.S. stations with normals, its annual mean of 49.9°F is warmer than 40%.
In the Köppen classification computed from these normals, Omak is BSk: cold semi-arid steppe. 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.
Which places near Omak share this climate record?
6 places have no NOAA station with 1991-2020 normals of their own, and this station is the nearest full record. A place's own climate can differ from these figures, by several degrees where it sits much higher or lower than the station, nearer the coast, or inside a large city's heat; for the larger places the next nearest records are named with their yearly mean, so the spread around them is visible, and places of 50,000 or more have their own page with NOAA's gridded normals.
- Okanogan, WA2,489 people · 7 mi SW
- Malott, WA708 people · 14 mi SW
- North Omak, WA368 people · 3 mi E
- Riverside, WA340 people · 4 mi N
- Conconully, WA198 people · 13 mi NW
- Disautel, WA46 people · 15 mi SE
Source: Census Bureau 2024 Gazetteer (place centers) and Vintage 2024 population estimates. Distance and direction from the station to each place's center.
Questions about Omak's climate
What is the coldest month in Omak?
December, with a normal high of 33°F and a normal low of 23°F. The warmest is July (89°F by day, 58°F at night).
What is the rainiest month in Omak?
December, with 1.95 in of precipitation in a normal year; the driest is August with 0.27 in.
What plant hardiness zone is Omak in?
The USDA's 2023 map puts Omak in zone 7a in ZIP code 98840, the nearest ZIP area. By the same method at Omak's NOAA station, the coldest night of a typical year reaches −1°F (21 years, 1991-2020): zone 6b.
How late can frost come in Omak?
In half of years the last 32°F night comes after April 30; in one year in ten it comes after May 15. Waiting until May 15 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Washington climateThe statewide normals and every place in the state
- Tonasket, WA22 miles from this station, 49.7°F a year
- Winthrop, WA31 miles from this station, 45.7°F a year
- Chief Joseph Dam, WA33 miles from this station, 51.0°F a year
- Methow, WA34 miles from this station, 50.0°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made