Average annual temperature is 12.7 °C
Absolute maximum temperature: 40.0 °C
Absolute minimum temperature: -10.1 °C
Number of sunny days: 213 days
Number of rainy days: 146 days
Number of snow days: 6 days
Look at detailed online map of Walla Walla County
* Weather data for Walla Walla County United States is based on climate observations for 2026 year
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Absolute maximum temperature (°C) | 13.6 | 13.7 | 16.0 | 29.1 | 33.9 | 35.8 | 38.9 | 40.0 | 33.3 | 26.5 | 16.2 | 15.6 |
| Average daytime temperature (°C) | 7.5 | 8.2 | 11.3 | 16.1 | 26.6 | 29.5 | 34.7 | 32.4 | 25.7 | 18.2 | 8.9 | 7.8 |
| Average temperature (°C) | 2.8 | 2.4 | 5.4 | 9.7 | 19.0 | 21.9 | 26.7 | 24.7 | 18.4 | 11.8 | 4.6 | 3.9 |
| Average night temperature (°C) | -0.5 | -1.4 | 0.9 | 4.6 | 12.4 | 15.0 | 18.9 | 18.2 | 13.1 | 7.1 | 1.7 | 1.3 |
| Absolute minimum temperature (°C) | -9.9 | -10.1 | -2.9 | -0.9 | 6.2 | 8.9 | 14.4 | 10.2 | 7.4 | -5.2 | -5.1 | -4.9 |
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Daylight maximum duration (h) | 9.0 | 11.0 | 12.0 | 14.0 | 15.0 | 15.0 | 15.0 | 14.0 | 13.0 | 11.0 | 10.0 | 8.0 |
| Daylight mean duration (h) | 9.1 | 10.3 | 11.9 | 13.6 | 15.0 | 15.7 | 15.4 | 14.1 | 12.6 | 10.9 | 9.5 | 8.7 |
| Daylight minimum duration (h) | 8.0 | 9.0 | 11.0 | 12.0 | 14.0 | 15.0 | 14.0 | 13.0 | 11.0 | 10.0 | 8.0 | 8.0 |
| Sunshine mean duration (h) | 4.9 | 6.2 | 7.9 | 9.3 | 12.8 | 13.2 | 14.0 | 11.0 | 9.3 | 8.1 | 4.8 | 3.3 |
| Precipitation (mm) | 17 | 31 | 41 | 46 | 11 | 8 | 1 | 13 | 25 | 30 | 48 | 56 |
| Sunny days | 13 | 11 | 9 | 12 | 20 | 27 | 30 | 23 | 18 | 20 | 17 | 13 |
| Rainy days | 15 | 15 | 21 | 18 | 11 | 3 | 1 | 8 | 12 | 11 | 13 | 18 |
| Snow days | 3 | 2 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
The best time to visit Walla Walla County during the most sunny months:
Months with the longest average daylight duration in Walla Walla County:
The largest precipitation sum in Walla Walla County is at