Priest Rapids Dam, Washington climate: Climate normals at a NOAA weather station
Priest Rapids Dam's normal year runs from 30°F January nights to 92°F July afternoons, with 7.5 inches of precipitation a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 13.3°C, January lows of −1°C, July highs of 33°C, 190 mm of precipitation a year.
- NOAA stationPriest Rapids Dam
- Station IDUSC00456747
- Location46.65°N 119.91°W
- Elevation428 ft (131 m)
On October 23, the normal high in Priest Rapids Dam is 61°F and the normal low 44°F, and the chance of measurable rain or snow is 25%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Priest Rapids Dam.
- Jan 41° 30°
- Feb 47° 32°
- Mar 57° 38°
- Apr 65° 45°
- May 75° 53°
- Jun 82° 60°
- Jul 92° 67°
- Aug 90° 66°
- Sep 80° 58°
- Oct 65° 46°
- Nov 50° 36°
- Dec 41° 30°
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 Priest Rapids Dam each month?
July is the warmest month, with normal highs of 92°F; January the coldest, with normal lows of 30°F. The most precipitation falls in December (1.40 in), the least in August (0.08 in).
| Month | High | Low | Mean | Precip. | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|
| January | 41°F | 30°F | 35.1°F | 1.08 | 10 | <1 | 20 | 9 h |
| February | 47°F | 32°F | 39.5°F | 0.62 | 8 | <1 | 14 | 10 h 20 min |
| March | 57°F | 38°F | 47.4°F | 0.74 | 7 | <1 | 7 | 11 h 50 min |
| April | 65°F | 45°F | 55.1°F | 0.55 | 5 | <1 | 1 | 13 h 30 min |
| May | 75°F | 53°F | 64.0°F | 0.55 | 5 | 2 | <1 | 15 h |
| June | 82°F | 60°F | 70.8°F | 0.54 | 4 | 6 | <1 | 15 h 50 min |
| July | 92°F | 67°F | 79.0°F | 0.21 | 2 | 19 | <1 | 15 h 30 min |
| August | 90°F | 66°F | 78.1°F | 0.08 | 1 | 18 | <1 | 14 h 20 min |
| September | 80°F | 58°F | 69.0°F | 0.15 | 2 | 5 | <1 | 12 h 40 min |
| October | 65°F | 46°F | 55.9°F | 0.65 | 7 | <1 | 2 | 11 h |
| November | 50°F | 36°F | 43.0°F | 0.91 | 9 | <1 | 11 | 9 h 30 min |
| December | 41°F | 30°F | 35.4°F | 1.40 | 10 | <1 | 21 | 8 h 40 min |
| Year (annual) | 65°F | 47°F | 56.0°F | 7.48 | 69 | 50 | 75 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. |
|---|---|---|---|---|
| January | 5°C | −1°C | 1.7°C | 27 mm |
| February | 8°C | 0°C | 4.2°C | 16 mm |
| March | 14°C | 3°C | 8.6°C | 19 mm |
| April | 19°C | 7°C | 12.8°C | 14 mm |
| May | 24°C | 12°C | 17.8°C | 14 mm |
| June | 28°C | 15°C | 21.6°C | 14 mm |
| July | 33°C | 19°C | 26.1°C | 5 mm |
| August | 32°C | 19°C | 25.6°C | 2 mm |
| September | 27°C | 14°C | 20.6°C | 4 mm |
| October | 19°C | 8°C | 13.3°C | 17 mm |
| November | 10°C | 2°C | 6.1°C | 23 mm |
| December | 5°C | −1°C | 1.9°C | 36 mm |
NOAA publishes no 1991-2020 snowfall normal for this station. The nearest record that keeps one, Moxee City (10 mi E) (16 miles away), gets 10 inches of snow in a normal year; elevation and distance can change that.
Source: NOAA NCEI 1991-2020 monthly normals, station USC00456747; 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 Priest Rapids Dam?
Normal highs sit between 65°F and 85°F in April, May, June, September and October. Of those, September has the fewest days with rain (2).
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 USC00456747.
When is the last frost at Priest Rapids Dam?
In Priest Rapids Dam, the last spring frost (32°F) comes after March 24 in half of years and after April 7 in one year in ten; the first autumn frost comes before November 4 in half of years and before October 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
- March 241 year in 10 after April 7; 9 in 10 after March 4
- First autumn frost, half of years before
- November 41 year in 10 before October 23; 9 in 10 before November 18
NOAA puts the median frost-free season at 222 days, and the season without a hard freeze (28°F) at 253 days.
A hard freeze (28°F) comes after March 5 in half of springs and before November 16 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Priest Rapids Dam in zone 7a in ZIP code 98950, 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 8a: the coldest night of a typical year reaches 11°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 Washington · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USC00456747; 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 Priest Rapids Dam?
In a normal year in Priest Rapids Dam, 50 days a year reach 90°F (11 of them 100°F or more), 75 nights fall to 32°F or colder and 69 days bring measurable precipitation.
- Days at 90°F or more
- 50a normal year
- Days at 100°F or more
- 11a normal year
- Nights at 32°F or colder
- 75a normal year
- Days that stay below freezing
- 13high of 32°F or less
- Days with 0.01 inch of precipitation
- 69a normal year
The highest temperature in this station's record (since 1956) is 112°F, on July 18, 1960; the lowest is −12°F, on January 31, 1996.
The wettest calendar year on that record is 1995, with 11.62 in; the snowiest season is 1961–62, with 12.8 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USC00456747; records: ACIS (NOAA Regional Climate Centers), station USC00456747. Records use complete months only; a month missing more than three days is left out.
How sunny is it at Priest Rapids Dam?
Over a year 81% of the sunlight that would reach the ground under clear skies gets through the clouds at Priest Rapids Dam, 4.2 kWh per square metre a day. July is the sunniest month (94%) and December the cloudiest (55%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 56% | 1.2 |
| February | 69% | 2.3 |
| March | 72% | 3.6 |
| April | 79% | 5.4 |
| May | 81% | 6.5 |
| June | 85% | 7.2 |
| July | 94% | 7.7 |
| August | 92% | 6.4 |
| September | 87% | 4.7 |
| October | 79% | 3.0 |
| November | 65% | 1.6 |
| December | 55% | 1.0 |
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 Priest Rapids Dam record?
A normal year at Priest Rapids Dam brings 4,514 heating degree days, 16% fewer than the median U.S. place (5,373), and 1,273 cooling degree days, 40% more than the median (908). Six months need 300 or more heating degree days, a monthly mean of about 55°F or colder. For gardens and crops, NOAA counts 3,845 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 927 | 0 |
| February | 714 | 0 |
| March | 546 | 0 |
| April | 302 | 5 |
| May | 102 | 69 |
| June | 19 | 193 |
| July | 1 | 436 |
| August | 1 | 406 |
| September | 33 | 155 |
| October | 294 | 10 |
| November | 659 | 0 |
| December | 918 | 0 |
| Year (annual) | 4,514 | 1,273 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00456747. 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 Priest Rapids Dam been warmer than normal?
Over 30 complete years from 1961 to 2025, the station's annual mean temperature rose at a fitted -0.0°F per century (−0.00°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 Priest Rapids Dam's climate compare?
Priest Rapids Dam is warmer than 96 of the 96 places with their own NOAA record in Washington, and wetter than 1. Across the 7,247 U.S. stations with normals, its annual mean of 56.0°F is warmer than 64%.
In the Köppen classification computed from these normals, Priest Rapids Dam 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 Priest Rapids Dam 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.
- Mattawa, WA3,784 people · 6 mi N
- Desert Aire, WA2,953 people · 3 mi N
- Schwana, WA352 people · 12 mi N
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 Priest Rapids Dam's climate
What is the coldest month at Priest Rapids Dam?
January, with a normal high of 41°F and a normal low of 30°F. The warmest is July (92°F by day, 67°F at night).
Does it snow at Priest Rapids Dam?
Yes. NOAA publishes no 1991-2020 snowfall normal for the station; the nearest record that keeps one, Moxee City (10 mi E) (16 miles away), records 10 inches of snow in a normal year.
What is the rainiest month at Priest Rapids Dam?
December, with 1.40 in of precipitation in a normal year; the driest is August with 0.08 in.
What plant hardiness zone is Priest Rapids Dam in?
The USDA's 2023 map puts Priest Rapids Dam in zone 7a in ZIP code 98950, the nearest ZIP area. By the same method at the station, the coldest night of a typical year reaches 11°F (19 years, 1991-2020): zone 8a.
How late can frost come at Priest Rapids Dam?
In half of years the last 32°F night comes after March 24; in one year in ten it comes after April 7. Waiting until April 7 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Washington climateThe statewide normals and every place in the state
- Moxee City (10 mi E), WA16 miles from this station, 50.2°F a year
- Smyrna, WA17 miles from this station, 53.4°F a year
- Sunnyside, WA23 miles from this station, 49.9°F a year
- Selah, WA28 miles from this station, 49.2°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made