Places › Seattle, WA › September
Seattle in September
One of the best months — score 95 of 100
Typical September days in Seattle reach about 71°F with nights near 53°F.
Avg high
71°F
1991–2020 normal
Avg low
53°F
1991–2020 normal
Rain total
1.74 in
in a typical September
Rain days
9
days with at least 0.01 in
Daylight
12h 30m
at mid-September, computed
What to pack for Seattle in September
- A light jacket or fleece for evenings.
- Layers — afternoons run about 18° warmer than mornings.
- A compact rain layer — about 9 days see rain in a typical September.
Every packing line is triggered by a number on this page — the rules are on How we pick.
September vs. the alternatives
The whole year in Seattle
JAN
47°F
Rain 18 days
Daylight 8h 49mFEB
50°F
Rain 16 days
Daylight 10h 10mMAR
54°F
Rain 18 days
Daylight 11h 44mAPR
59°F
Rain 16 days
Daylight 13h 33mMAY
65°F
Rain 12 days
Daylight 15h 06mJUN
70°F
★ Best
Rain 10 days
Daylight 15h 57mJUL
76°F
★ Best
Rain 5 days
Daylight 15h 37mAUG
77°F
★ Best
Rain 6 days
Daylight 14h 16mSEP
71°F
Rain 9 days
Daylight 12h 30mOCT
60°F
Rain 14 days
Daylight 10h 46mNOV
52°F
Rain 19 days
Daylight 9h 13mDEC
46°F
Rain 20 days
Daylight 8h 27m
47°F
Rain 18 days
Daylight 8h 49mFEB
50°F
Rain 16 days
Daylight 10h 10mMAR
54°F
Rain 18 days
Daylight 11h 44mAPR
59°F
Rain 16 days
Daylight 13h 33mMAY
65°F
Rain 12 days
Daylight 15h 06mJUN
70°F
★ Best
Rain 10 days
Daylight 15h 57mJUL
76°F
★ Best
Rain 5 days
Daylight 15h 37mAUG
77°F
★ Best
Rain 6 days
Daylight 14h 16mSEP
71°F
Rain 9 days
Daylight 12h 30mOCT
60°F
Rain 14 days
Daylight 10h 46mNOV
52°F
Rain 19 days
Daylight 9h 13mDEC
46°F
Rain 20 days
Daylight 8h 27m
Averages are the 1991–2020 climate normals (NOAA National Centers for Environmental Information) for the station named on each page. Rain days = days with at least 0.01 in of precipitation. Daylight is computed for the middle of the month.