Monthly Historical AveragesMercer Island, WA
Average Temperature
High
15°
Feels 14
Low
6°
Feels 4
Average Precipitation
14 Days
75.4mm
0cm
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Daily Historical Averages
S
M
T
W
T
F
S
ForecastThursday, April 9, 2026
Day
18°Feels 18
Wind
15 km/h N
Gust
20 km/h
Humidity
43%
P.O.P
10%
Night
6°Feels 5
Wind
13 km/h NE
Gust
18 km/h
Humidity
93%
P.O.P
20%
Historical AveragesApr 9
High
Feels
Low
Feels
Precip Frequency
Total Daylight
Humidity