Sumas, WA Weather
Sumas, WA climate is mild during summer when temperatures tend to be in the 60's and very cold during winter when temperatures tend to be in the 30's.
The warmest month of the year is August with an average maximum temperature of 75.90 degrees Fahrenheit, while the coldest month of the year is January with an average minimum temperature of 32.10 degrees Fahrenheit.
Temperature variations between night and day tend to be moderate during summer with a difference that can reach 25 degrees Fahrenheit, and fairly limited during winter with an average difference of 12 degrees Fahrenheit.
The annual average precipitation at Sumas is 45.77 Inches. Rainfall in is fairly evenly distributed throughout the year. The wettest month of the year is November with an average rainfall of 6.36 Inches.