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Sumas, WA Climate
1991 to 2020 normals at Clearbrook, 3.3 mi from the center of Sumas, elevation 64 ft.
Average weather by month
Select a month for daily normals and last year's weather
| Month | Range | High | Low | Precip. | Snow |
|---|---|---|---|---|---|
| January | 44° | 32° | 6.98 in | 3.1 in | |
| February | 48° | 33° | 3.85 in | 2.7 in | |
| March | 53° | 36° | 5.00 in | 1.0 in | |
| April | 59° | 39° | 3.97 in | 0.1 in | |
| May | 66° | 45° | 3.17 in | 0.0 in | |
| June | 70° | 49° | 2.39 in | 0.0 in | |
| July | 76° | 51° | 1.45 in | 0.0 in | |
| August | 77° | 50° | 1.50 in | 0.0 in | |
| September | 71° | 47° | 2.93 in | 0.0 in | |
| October | 59° | 42° | 5.31 in | 0.0 in | |
| November | 49° | 36° | 7.11 in | 1.3 in | |
| December | 43° | 32° | 6.19 in | 2.6 in | |
| Year | 60° | 49.85 in | 10.8 in |
Frequently asked questions
- What is the hottest month in Sumas, WA?
- August is the warmest month, with a normal high of 77°F at Clearbrook.
- What is the coldest month in Sumas, WA?
- January is the coldest month, with a normal low of 32°F.
- What is the wettest month in Sumas, WA?
- November has the most precipitation on average, about 7.11 inches.