Kennewick, Washington climate: Normal weather by month, frost dates and records
Kennewick's normal year runs from 29°F January nights to 91°F July afternoons, with 7.9 inches of precipitation a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 12.8°C, January lows of −2°C, July highs of 33°C, 200 mm of precipitation a year.
- NOAA stationKennewick
- Station IDUSC00454154
- Location46.21°N 119.10°W
- Elevation390 ft (119 m)
- From the center4 miles
- Population86,728
On October 24, the normal high in Kennewick is 62°F and the normal low 40°F, and the chance of measurable rain or snow is 23%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Kennewick.
- Jan 42° 29°
- Feb 48° 31°
- Mar 58° 36°
- Apr 66° 42°
- May 75° 50°
- Jun 82° 56°
- Jul 91° 62°
- Aug 90° 61°
- Sep 81° 53°
- Oct 66° 43°
- Nov 51° 35°
- Dec 42° 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 in Kennewick each month?
July is the warmest month, with normal highs of 91°F; January the coldest, with normal lows of 29°F. The most precipitation falls in January (1.13 in), the least in August (0.17 in).
Each month has its own page with the day-by-day normals, the month's records and its recent years:
| Month | High | Low | Mean | Precip. | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|
| January | 42°F | 29°F | 35.5°F | 1.13 | 11 | <1 | 18 | 9 h |
| February | 48°F | 31°F | 39.5°F | 0.79 | 8 | <1 | 16 | 10 h 20 min |
| March | 58°F | 36°F | 47.0°F | 0.66 | 8 | <1 | 8 | 11 h 50 min |
| April | 66°F | 42°F | 54.3°F | 0.61 | 7 | <1 | 1 | 13 h 30 min |
| May | 75°F | 50°F | 62.7°F | 0.84 | 6 | 2 | <1 | 15 h |
| June | 82°F | 56°F | 69.2°F | 0.58 | 5 | 6 | <1 | 15 h 50 min |
| July | 91°F | 62°F | 76.8°F | 0.21 | 2 | 19 | <1 | 15 h 30 min |
| August | 90°F | 61°F | 75.8°F | 0.17 | 2 | 17 | <1 | 14 h 10 min |
| September | 81°F | 53°F | 66.8°F | 0.26 | 3 | 4 | <1 | 12 h 40 min |
| October | 66°F | 43°F | 54.5°F | 0.67 | 6 | <1 | 2 | 11 h |
| November | 51°F | 35°F | 42.9°F | 0.87 | 9 | <1 | 11 | 9 h 30 min |
| December | 42°F | 30°F | 35.6°F | 1.08 | 11 | <1 | 19 | 8 h 40 min |
| Year (annual) | 66°F | 44°F | 55.0°F | 7.87 | 77 | 48 | 76 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. |
|---|---|---|---|---|
| January | 5°C | −2°C | 1.9°C | 29 mm |
| February | 9°C | −1°C | 4.2°C | 20 mm |
| March | 15°C | 2°C | 8.3°C | 17 mm |
| April | 19°C | 6°C | 12.4°C | 15 mm |
| May | 24°C | 10°C | 17.1°C | 21 mm |
| June | 28°C | 14°C | 20.7°C | 15 mm |
| July | 33°C | 17°C | 24.9°C | 5 mm |
| August | 32°C | 16°C | 24.3°C | 4 mm |
| September | 27°C | 12°C | 19.3°C | 7 mm |
| October | 19°C | 6°C | 12.5°C | 17 mm |
| November | 11°C | 2°C | 6.1°C | 22 mm |
| December | 5°C | −1°C | 2.0°C | 27 mm |
NOAA publishes no 1991-2020 snowfall normal for this station. The nearest record that keeps one, Ice Harbor Dam (11 miles away), gets 2 inches of snow in a normal year; elevation and distance can change that.
Source: NOAA NCEI 1991-2020 monthly normals, station USC00454154; 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 Kennewick?
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 (3).
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 USC00454154.
When is the last frost in Kennewick?
In Kennewick, the last spring frost (32°F) comes after March 28 in half of years and after April 10 in one year in ten; the first autumn frost comes before October 30 in half of years and before October 18 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 281 year in 10 after April 10; 9 in 10 after March 9
- First autumn frost, half of years before
- October 301 year in 10 before October 18; 9 in 10 before November 15
NOAA puts the median frost-free season at 216 days, and the season without a hard freeze (28°F) at 246 days.
A hard freeze (28°F) comes after March 8 in half of springs and before November 11 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Kennewick in zone 7b across its 2 ZIP code areas (7b in 99336, the largest). By the map's own method, the average of each year's coldest night over 1991-2020, Kennewick's NOAA station is in zone 8a: the coldest night of a typical year reaches 10°F (30 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 USC00454154; 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.
What hardiness zone is each Kennewick ZIP code in?
The USDA's 2023 map gives each ZIP code area one zone. Kennewick's 2 ZIP code areas are all in zone 7b. Each ZIP's frost dates are in the frost tool.
Source: USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026; ZIP areas in the place: Census Bureau 2020 ZCTA-to-place relationship file. A ZIP area counts when at least a tenth of its land (and 0.5 km²) lies in the place.
How hot and how cold does it get in Kennewick?
In a normal year in Kennewick, 48 days a year reach 90°F (8 of them 100°F or more), 76 nights fall to 32°F or colder and 77 days bring measurable precipitation.
- Days at 90°F or more
- 48a normal year
- Days at 100°F or more
- 8a normal year
- Nights at 32°F or colder
- 76a normal year
- Days that stay below freezing
- 15high of 32°F or less
- Days with 0.01 inch of precipitation
- 77a normal year
The highest temperature in this station's record (since 1894) is 115°F, on July 27, 1939; the lowest is −29°F, on December 13, 1919.
The wettest calendar year on that record is 1948, with 12.90 in; the snowiest season is 1955–56, with 34.3 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USC00454154; records: ACIS (NOAA Regional Climate Centers), station USC00454154. Records use complete months only; a month missing more than three days is left out.
How sunny is Kennewick?
Over a year 81% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Kennewick, 4.2 kWh per square metre a day. July is the sunniest month (94%) and December the cloudiest (55%). Among the 459 U.S. places of 50,000 or more, that ranks tied 111th (with 13 others) in sunshine.
| 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 much heating and cooling does Kennewick need?
A normal year in Kennewick brings 4,619 heating degree days, 14% fewer than the median U.S. place (5,373), and 1,020 cooling degree days, 12% more 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 3,502 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 916 | 0 |
| February | 714 | 0 |
| March | 558 | 0 |
| April | 323 | 3 |
| May | 125 | 53 |
| June | 25 | 151 |
| July | 1 | 367 |
| August | 2 | 337 |
| September | 49 | 105 |
| October | 330 | 5 |
| November | 663 | 0 |
| December | 913 | 0 |
| Year (annual) | 4,619 | 1,020 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00454154. 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 Kennewick been warmer than normal lately?
2025 averaged 57.5°F, 2.5°F above the 1991-2020 normal of 55.0°F. 4 of the 5 complete years since 2021 ran warmer than the normal.
| Year | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 57.3°F | +2.3°F | 7.18 |
| 2022 | 54.5°F | −0.5°F | 9.92 |
| 2023 | 56.1°F | +1.1°F | 5.71 |
| 2024 | 56.5°F | +1.5°F | 9.33 |
| 2025 | 57.5°F | +2.5°F | 9.22 |
Over 90 complete years from 1886 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 USC00454154; trend: NOAA GHCN-Monthly v4. A year counts only with all twelve months complete.
How does Kennewick's climate compare?
Kennewick is warmer than 95 of the other 95 places with their own NOAA record in Washington, and wetter than 8. Across the 7,247 U.S. stations with normals, its annual mean of 55.0°F is warmer than 60%.
In the Köppen classification computed from these normals, Kennewick 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 Kennewick share this climate record?
2 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.
- Finley, WA5,734 people · 4 mi SE
- Burbank, WA3,645 people · 6 mi E
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 Kennewick's climate
What is the coldest month in Kennewick?
January, with a normal high of 42°F and a normal low of 29°F. The warmest is July (91°F by day, 62°F at night).
Does it snow in Kennewick?
Yes. NOAA publishes no 1991-2020 snowfall normal for Kennewick's NOAA station; the nearest record that keeps one, Ice Harbor Dam (11 miles away), records 2 inches of snow in a normal year.
What is the rainiest month in Kennewick?
January, with 1.13 in of precipitation in a normal year; the driest is August with 0.17 in.
What plant hardiness zone is Kennewick in?
The USDA's 2023 map puts Kennewick in zone 7b across its 2 ZIP code areas (7b in 99336, the largest). By the same method at Kennewick's NOAA station, the coldest night of a typical year reaches 10°F (30 years, 1991-2020): zone 8a.
How late can frost come in Kennewick?
In half of years the last 32°F night comes after March 28; in one year in ten it comes after April 10. Waiting until April 10 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Kennewick in OctoberThis month day by day, its records and recent years
- Washington climateThe statewide normals and every place in the state
- Pasco, WA4 miles from this station, 53.3°F a year
- Richland, WA11 miles from this station, 53.6°F a year
- Ice Harbor Dam, WA11 miles from this station, 54.0°F a year
- Sagemoor, WA13 miles from this station, 52.0°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made