Home › Cities › United States › Washington › Richland
Richland, Washington climate
BWk Cold desert
Richland has a seasonal cool-temperate climate (Cold desert, Köppen BWk). The hottest month is July with an average daily high near 32°C, while the coldest is December averaging around −2°C at night. Precipitation totals about 185 mm a year and is strongly seasonal — December alone averages 27 mm while August barely receives 3 mm.
Temperature & precipitation
Daily high–low temperature range with the monthly average, plus monthly precipitation · 1991–2020 normals · hover a month for the exact figuresClear vs cloudy days
Share of days each month that are clear, partly cloudy or cloudy · 1991–2020 · hover a month for the day countsRichland climate normals (1991–2020)
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high (°C) | 5 | 9 | 14 | 18 | 23 | 27 | 32 | 31 | 26 | 18 | 9 | 4 |
| Avg temp (°C) | 2 | 4 | 8 | 12 | 16 | 20 | 24 | 23 | 18 | 12 | 5 | 1 |
| Avg low (°C) | −2 | −1 | 2 | 5 | 9 | 12 | 16 | 15 | 11 | 5 | 1 | −2 |
| Precipitation (mm) | 26 | 17 | 16 | 16 | 16 | 14 | 6 | 3 | 7 | 14 | 22 | 27 |
| Jan – Jun | Jan | Feb | Mar | Apr | May | Jun |
|---|---|---|---|---|---|---|
| Avg high (°C) | 5 | 9 | 14 | 18 | 23 | 27 |
| Avg temp (°C) | 2 | 4 | 8 | 12 | 16 | 20 |
| Avg low (°C) | −2 | −1 | 2 | 5 | 9 | 12 |
| Precipitation (mm) | 26 | 17 | 16 | 16 | 16 | 14 |
| Jul – Dec | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|
| Avg high (°C) | 32 | 31 | 26 | 18 | 9 | 4 |
| Avg temp (°C) | 24 | 23 | 18 | 12 | 5 | 1 |
| Avg low (°C) | 16 | 15 | 11 | 5 | 1 | −2 |
| Precipitation (mm) | 6 | 3 | 7 | 14 | 22 | 27 |
How often — frequency of weather events
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Days with measurable rain (days) | 11 | 8 | 8 | 7 | 7 | 5 | 2 | 2 | 3 | 6 | 10 | 12 |
| Days with high ≥ 32°C (days) | — | — | — | — | 1 | 4 | 16 | 14 | 2 | 0.1 | — | — |
| Days with low ≤ 0°C (days) | 20 | 17 | 10 | 2 | — | — | — | — | 0.1 | 3 | 13 | 22 |
| Days with snowfall ≥ 2.5 cm (days) | 0.2 | 0.1 | 0.1 | — | — | — | — | — | — | — | 0.0 | 0.2 |
| Jan – Jun | Jan | Feb | Mar | Apr | May | Jun |
|---|---|---|---|---|---|---|
| Days with measurable rain (days) | 11 | 8 | 8 | 7 | 7 | 5 |
| Days with high ≥ 32°C (days) | — | — | — | — | 1 | 4 |
| Days with low ≤ 0°C (days) | 20 | 17 | 10 | 2 | — | — |
| Days with snowfall ≥ 2.5 cm (days) | 0.2 | 0.1 | 0.1 | — | — | — |
| Jul – Dec | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|
| Days with measurable rain (days) | 2 | 2 | 3 | 6 | 10 | 12 |
| Days with high ≥ 32°C (days) | 16 | 14 | 2 | 0.1 | — | — |
| Days with low ≤ 0°C (days) | — | — | 0.1 | 3 | 13 | 22 |
| Days with snowfall ≥ 2.5 cm (days) | — | — | — | — | 0.0 | 0.2 |
Sky & atmosphere
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Cloud cover (%) | 75 | 68 | 67 | 62 | 58 | 50 | 30 | 31 | 40 | 56 | 70 | 74 |
| Clear days (≤ 30% cloud) | 2 | 4 | 4 | 5 | 7 | 9 | 19 | 18 | 14 | 8 | 3 | 2 |
| Partly cloudy days (30–70%) | 9 | 8 | 10 | 11 | 10 | 11 | 8 | 9 | 9 | 10 | 10 | 9 |
| Cloudy days (≥ 70%) | 21 | 16 | 17 | 14 | 13 | 9 | 4 | 4 | 7 | 12 | 17 | 20 |
| Relative humidity (%) | 84 | 74 | 65 | 57 | 51 | 46 | 40 | 40 | 46 | 60 | 75 | 82 |
| Wind speed (mph) | 4.9 | 5.3 | 5.5 | 5.5 | 5.2 | 5.5 | 4.9 | 4.7 | 4.5 | 4.8 | 4.9 | 4.8 |
| Jan – Jun | Jan | Feb | Mar | Apr | May | Jun |
|---|---|---|---|---|---|---|
| Cloud cover (%) | 75 | 68 | 67 | 62 | 58 | 50 |
| Clear days (≤ 30% cloud) | 2 | 4 | 4 | 5 | 7 | 9 |
| Partly cloudy days (30–70%) | 9 | 8 | 10 | 11 | 10 | 11 |
| Cloudy days (≥ 70%) | 21 | 16 | 17 | 14 | 13 | 9 |
| Relative humidity (%) | 84 | 74 | 65 | 57 | 51 | 46 |
| Wind speed (mph) | 4.9 | 5.3 | 5.5 | 5.5 | 5.2 | 5.5 |
| Jul – Dec | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|
| Cloud cover (%) | 30 | 31 | 40 | 56 | 70 | 74 |
| Clear days (≤ 30% cloud) | 19 | 18 | 14 | 8 | 3 | 2 |
| Partly cloudy days (30–70%) | 8 | 9 | 9 | 10 | 10 | 9 |
| Cloudy days (≥ 70%) | 4 | 4 | 7 | 12 | 17 | 20 |
| Relative humidity (%) | 40 | 40 | 46 | 60 | 75 | 82 |
| Wind speed (mph) | 4.9 | 4.7 | 4.5 | 4.8 | 4.9 | 4.8 |
Methodology & sources
Temperature & precipitation — the official 1991–2020 climate normals from NOAA's U.S. Climate Normals, measured at Richland (NOAA GHCN station USC00457015), about 3 km from the city centre.
Cloud, humidity, wind & sunshine — modelled estimates from NASA POWER, NASA's satellite-and-reanalysis climatology. This is the standard global source for atmospheric variables, which are not measured at most weather stations.