Northport, Washington climate: Normal weather by month, frost dates and records
Northport's normal year runs from 21°F January nights to 85°F July afternoons, with 20.3 inches of precipitation and 47 inches of snow a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 8.0°C, January lows of −6°C, July highs of 30°C, 516 mm of precipitation a year.
- NOAA stationNorthport
- Station IDUSC00455946
- Location48.90°N 117.83°W
- Elevation1,497 ft (456 m)
- From the center2 miles
- Population291
On October 23, the normal high in Northport is 52°F and the normal low 32°F, and the chance of measurable rain or snow is 32%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Northport.
- Jan 31° 21°
- Feb 39° 22°
- Mar 49° 27°
- Apr 60° 33°
- May 70° 41°
- Jun 75° 47°
- Jul 85° 51°
- Aug 86° 50°
- Sep 75° 43°
- Oct 57° 34°
- Nov 41° 27°
- Dec 32° 22°
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 Northport each month?
July is the warmest month, with normal highs of 85°F; January the coldest, with normal lows of 21°F. The most precipitation falls in December (2.47 in), the least in August (0.61 in).
| Month | High | Low | Mean | Precip. | Snow | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|---|
| January | 31°F | 21°F | 25.8°F | 2.24 | 15.8 | 12 | <1 | 27 | 8 h 40 min |
| February | 39°F | 22°F | 30.3°F | 1.32 | 5.9 | 9 | <1 | 23 | 10 h 10 min |
| March | 49°F | 27°F | 38.1°F | 1.64 | 1.7 | 10 | <1 | 23 | 11 h 50 min |
| April | 60°F | 33°F | 46.1°F | 1.68 | 0.1 | 9 | <1 | 12 | 13 h 40 min |
| May | 70°F | 41°F | 55.2°F | 2.12 | 0.0 | 10 | 1 | 2 | 15 h 10 min |
| June | 75°F | 47°F | 60.9°F | 2.44 | 0.0 | 10 | 3 | <1 | 16 h 10 min |
| July | 85°F | 51°F | 68.0°F | 1.01 | 0.0 | 5 | 13 | <1 | 15 h 50 min |
| August | 86°F | 50°F | 67.7°F | 0.61 | 0.0 | 4 | 14 | <1 | 14 h 30 min |
| September | 75°F | 43°F | 58.9°F | 0.97 | 0.0 | 5 | 3 | 1 | 12 h 40 min |
| October | 57°F | 34°F | 45.4°F | 1.56 | 0.2 | 9 | <1 | 11 | 10 h 50 min |
| November | 41°F | 27°F | 33.9°F | 2.24 | 5.9 | 12 | <1 | 19 | 9 h 10 min |
| December | 32°F | 22°F | 26.5°F | 2.47 | 17.0 | 13 | <1 | 28 | 8 h 20 min |
| Year (annual) | 58°F | 35°F | 46.4°F | 20.30 | 46.6 | 108 | 33 | 146 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. | Snow |
|---|---|---|---|---|---|
| January | 0°C | −6°C | −3.4°C | 57 mm | 40 cm |
| February | 4°C | −6°C | −0.9°C | 34 mm | 15 cm |
| March | 10°C | −3°C | 3.4°C | 42 mm | 4 cm |
| April | 15°C | 0°C | 7.8°C | 43 mm | 0 cm |
| May | 21°C | 5°C | 12.9°C | 54 mm | 0 cm |
| June | 24°C | 8°C | 16.1°C | 62 mm | 0 cm |
| July | 30°C | 10°C | 20.0°C | 26 mm | 0 cm |
| August | 30°C | 10°C | 19.8°C | 15 mm | 0 cm |
| September | 24°C | 6°C | 14.9°C | 25 mm | 0 cm |
| October | 14°C | 1°C | 7.4°C | 40 mm | 1 cm |
| November | 5°C | −3°C | 1.1°C | 57 mm | 15 cm |
| December | 0°C | −6°C | −3.1°C | 63 mm | 43 cm |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00455946; 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 Northport?
Normal highs sit between 65°F and 85°F in May, June and September. Of those, September has the fewest days with rain (5).
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 USC00455946.
When is the last frost in Northport?
In Northport, the last spring frost (32°F) comes after May 8 in half of years and after May 26 in one year in ten; the first autumn frost comes before October 1 in half of years and before September 15 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 81 year in 10 after May 26; 9 in 10 after April 27
- First autumn frost, half of years before
- October 11 year in 10 before September 15; 9 in 10 before October 14
NOAA puts the median frost-free season at 143 days, and the season without a hard freeze (28°F) at 170 days.
A hard freeze (28°F) comes after April 26 in half of springs and before October 13 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Northport in zone 6b in ZIP code 99157, the nearest ZIP area. By the map's own method, the average of each year's coldest night over 1991-2020, Northport's NOAA station is in zone 6b: the coldest night of a typical year reaches −2°F (24 complete years).
Frost dates for every NOAA station in Washington · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USC00455946; 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 Northport?
In a normal year in Northport, 33 days a year reach 90°F (3 of them 100°F or more), 146 nights fall to 32°F or colder and 108 days bring measurable precipitation.
- Days at 90°F or more
- 33a normal year
- Days at 100°F or more
- 3a normal year
- Nights at 32°F or colder
- 146a normal year
- Days that stay below freezing
- 29high of 32°F or less
- Days with 0.01 inch of precipitation
- 108a normal year
- Days with 1 inch of snow or more
- 17a normal year
The highest temperature in this station's record (since 1899) is 113°F, on June 30, 2021; the lowest is −32°F, on January 11, 1909.
The wettest calendar year on that record is 1941, with 28.19 in; the snowiest season is 1968–69, with 111.0 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USC00455946; records: ACIS (NOAA Regional Climate Centers), station USC00455946. Records use complete months only; a month missing more than three days is left out.
How sunny is Northport?
Over a year 71% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Northport, 3.6 kWh per square metre a day. July is the sunniest month (87%) and December the cloudiest (48%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 50% | 1.0 |
| February | 60% | 1.9 |
| March | 59% | 2.9 |
| April | 65% | 4.4 |
| May | 71% | 5.7 |
| June | 70% | 6.0 |
| July | 87% | 7.2 |
| August | 86% | 5.9 |
| September | 79% | 4.2 |
| October | 68% | 2.4 |
| November | 53% | 1.2 |
| December | 48% | 0.8 |
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 Northport need?
A normal year in Northport brings 7,048 heating degree days, 31% more than the median U.S. place (5,373), and 301 cooling degree days, 67% fewer than the median (908). Eight months need 300 or more heating degree days, a monthly mean of about 55°F or colder. For gardens and crops, NOAA counts 1,964 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,215 | 0 |
| February | 970 | 0 |
| March | 832 | 0 |
| April | 566 | 0 |
| May | 308 | 4 |
| June | 149 | 27 |
| July | 35 | 129 |
| August | 37 | 121 |
| September | 202 | 19 |
| October | 608 | 0 |
| November | 933 | 0 |
| December | 1,193 | 0 |
| Year (annual) | 7,048 | 301 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00455946. 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 Northport been warmer than normal lately?
2025 averaged 48.9°F, 2.5°F above the 1991-2020 normal of 46.4°F. 4 of the 5 complete years since 2021 ran warmer than the normal.
| Year | Mean | Against normal | Precip. | Snow |
|---|---|---|---|---|
| 2021 | 47.7°F | +1.3°F | 17.60 | 47.7 |
| 2022 | 45.7°F | −0.7°F | 16.79 | 71.7 |
| 2023 | 48.5°F | +2.1°F | 19.01 | 22.9 |
| 2024 | 48.5°F | +2.1°F | 22.54 | 33.2 |
| 2025 | 48.9°F | +2.5°F | 19.09 | 22.3 |
Over 83 complete years from 1900 to 2025, the station's annual mean temperature rose at a fitted 2.1°F per century (+0.12°C per decade). A fitted rate summarizes the whole record; single years swing well above and below it.
Source: observed years: ACIS, station USC00455946; trend: NOAA GHCN-Monthly v4. A year counts only with all twelve months complete.
How does Northport's climate compare?
Northport is warmer than 9 of the other 95 places with their own NOAA record in Washington, and wetter than 43. Across the 7,247 U.S. stations with normals, its annual mean of 46.4°F is warmer than 25%.
In the Köppen classification computed from these normals, Northport is Dsb: continental, dry-summer, warm 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.
Which places near Northport share this climate record?
3 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.
- Barstow, WA76 people · 16 mi SW
- Orient, WA69 people · 17 mi W
- Laurier, WA0 people · 19 mi W
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 Northport's climate
What is the coldest month in Northport?
January, with a normal high of 31°F and a normal low of 21°F. The warmest is July (85°F by day, 51°F at night).
Does it snow in Northport?
Yes: 47 inches in a normal year, falling on 24 days with 0.1 inch or more, the most in December (17.0 inches).
What is the rainiest month in Northport?
December, with 2.47 in of precipitation in a normal year; the driest is August with 0.61 in.
What plant hardiness zone is Northport in?
The USDA's 2023 map puts Northport in zone 6b in ZIP code 99157, the nearest ZIP area. By the same method at Northport's NOAA station, the coldest night of a typical year reaches −2°F (24 years, 1991-2020): zone 6b.
How late can frost come in Northport?
In half of years the last 32°F night comes after May 8; in one year in ten it comes after May 26. Waiting until May 26 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Washington climateThe statewide normals and every place in the state
- Boundary Dam, WA22 miles from this station, 46.0°F a year
- Colville, WA24 miles from this station, 48.9°F a year
- Chewelah, WA43 miles from this station, 46.3°F a year
- Republic, WA45 miles from this station, 43.8°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made