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Monthly
Precipitation
Temperature
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Temperature Unit Selection
°Celsius
°Fahrenheit
Monthly Historical Averages
Mount Si Golf Course, WA
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May
Average Temperature
High
18°
Feels 18
Low
8°
Feels 7
Average Precipitation
11 Days
Rain amount
54.2mm
Snow amount
0.1cm
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Daily Historical Averages
May 2026
S
M
T
W
T
F
S
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
17°
19
16°
20
17°
21
21°
22
21°
23
20°
24
16°
25
13°
26
16°
27
14°
28
12°
29
13°
30
16°
31
18°
Forecast
Monday, May 18, 2026
Day
17°
Feels 17
Wind
15 km/h W
Gust
23 km/h
Humidity
48%
P.O.P
30%
Night
8°
Feels 7
Wind
14 km/h SE
Gust
21 km/h
Humidity
93%
P.O.P
30%
Historical Averages
May 18
High
Feels
Low
Feels
Precip Frequency
Total Daylight
Humidity
Historical Averages are based on data recorded from 2000 onwards.