Humid cities · Washington
How humid is Seattle in summer?
Across June, July and August, the dew point in Seattle averages about 51.7°F, which is comfortable on the usual dew point scale.
August is the muggiest month, with the dew point averaging about 53.4°F. On NOAA’s hour by hour normals, no hour of the year averages a dew point of 65°F or more, though a muggy spell can still turn up. That makes it the 25th driest summer air of the 124 US cities we track.
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The highest dew point in the forecast for the next 48 hours is about 53°F, which is comfortable.
Seattle’s summer dew point averages about 51.7°F, and August reaches about 53. Nine months of drizzle, then a summer too dry to be sticky.
Live 48-hour forecast from OpenWeatherMap, refreshed about every half hour. Alerts from the National Weather Service.
Summer humidity at a glance
| Dew point, June to August | 51.7°F |
|---|---|
| Muggiest month | August, 53.4°F |
| Hours a year at a 65°F dew point or more | none |
| How summer feels | comfortable |
The dew point is the temperature the air would have to cool to for dew to form, so the higher it is, the more water the air holds. Forecasters usually call under 55°F comfortable, 55 to 65°F sticky and 65°F or more muggy; 70°F or more feels tropical.
Cities with about the same summer air
- Fresno, California: about 51.5°F
- Eugene, Oregon: about 51.3°F
- Olympia, Washington: about 51.3°F
More about the weather here
Source: NOAA U.S. Climate Normals, hourly, 1991 to 2020, station USW00024233. Average dew points, not the stickiest days.