Weather in Seattle in september
Climate normals based on 10 years of historical data for Seattle, USA.
Average high
21°C
Average low
12°C
Rainfall
67 mm
10 rainy days
Sunshine
4.4h/day
Niiskus
73%
How Hot Is Seattle in september?
September keeps Seattle warm but with noticeable cooling at night: 21°C peaks, 12°C lows.
Sunshine Hours in september
Seattle's September averages 4.4h of direct sun — cloud cover varies day to day.
Does It Rain In Seattle In september?
Rain comes in bursts: Seattle averages 67mm across 10 days in September.
Is Seattle Humid In september?
High levels of humidity in Seattle year-round (about 73%) will make it feel warmer than the thermometer suggests.
Wind In Seattle In september
Breezes around 13 kph in Seattle this September — comfortable for outdoor activity.
Cloud Cover In Seattle In september
Grey, cloudy days are the norm: 57% average cover in Seattle.
Cities With Similar Weather In september
Weather in Seattle, month by month
| Month | High / Low | Vihm | |
|---|---|---|---|
| Jaanuari ilm | 8°C / 3°C | 188mm | Details → |
| Veebruari ilm | 8°C / 2°C | 124mm | Details → |
| Märtsi ilm | 11°C / 3°C | 109mm | Details → |
| Aprilli ilm | 14°C / 5°C | 87mm | Details → |
| Mai ilm | 19°C / 9°C | 55mm | Details → |
| Juuni ilm | 22°C / 11°C | 54mm | Details → |
| Juuli ilm | 26°C / 14°C | 15mm | Details → |
| Augusti ilm | 26°C / 15°C | 27mm | Details → |
| Septembri ilm | 21°C / 12°C | 67mm | |
| Oktoobri ilm | 16°C / 8°C | 134mm | Details → |
| Novembri ilm | 10°C / 5°C | 192mm | Details → |
| Detsembri ilm | 7°C / 3°C | 202mm | Details → |