Seattle Weather in July

Seattle, Washington enjoys spectacular summer weather during July. This is the sunniest and least humid month of the year, and often the least rainy.

This page gives detailed information on the typical July temperature, precipitation, sun, humidity, wind and storms for Seattle. The weather measurements are averages based on climate data gathered at Seattle — Tacoma International Airport, located south of the city center.

Temperature Weather iconTemperature

77 °F July average high 25 °C
57 °F July average low 14 °C

The year's highest overall temperatures begin on July 21st and continue into August. On these dates Seattle has daily highs averaging 79 degrees Fahrenheit (26 degrees Celsius) and lows of 58 °F (14 °C).

25 days 70 °F max. or more (21 °C)
28 days 60 °F min. or less (16 °C)

Usually every day in July the temperature rises to over 60 °F (16 °C) at Seattle. The city averages ten days this month when the thermometer reaches into the 80s °F (over 27 °C). Temperatures of 90 °F (32 °C) or above typically occur here once or twice during July.

Most July nights, the temperature drops into the 50s °F (10 to 15 °C). A night this month can cool down to 50 °F (10 °C), but that doesn't happen every year.

Rainy Weather iconRain

0.6 in total precipitation 15 mm
5 days of rain

This is the one of the driest months for Seattle. Half the time, the city receives 0.2 to 1.0 inches (4 to 26 mm) of rainfall in July. One in four years has drier weather, while another one in four is wetter.

Sunny Weather iconSun

63 % sunshine
12 days clear skies

July is the sunniest month of the year for Seattle. The sun's rays reach the ground here during 63 percent of daylight hours on average, for a total of 303 hours in the month. Typically on 12 days this month the sky is mainly clear, with at most 30 percent cloud cover.

Sunlight in July at Seattle lasts for 15 hours and 31 minutes a day on average. The longest day of the month is the 1st with 15 hours and 55 minutes of daylight. By the end of the month, the days have shortened to 14:59 from sunrise to sunset. These durations can vary by a minute or two from year to year.

Humid Weather iconHumidity

65 % July average humidity

The relative humidity in Seattle during July usually peaks at 81 percent in the morning then drops to 49 percent by late afternoon.

Local Time1 am4 am7 am10 am1 pm4 pm7 pm10 pm
Humidity % 75 81 78 65 54 49 54 68

Windy Weather iconWind

8.1 mph July wind speed average 13.0 kph

July is less windy than most other months in Seattle.

Stormy Weather iconStorms

0 days rainfall of 0.5 inches (13 mm) or more
1 day with thunderstorms in July

July is one of the months when Seattle is most likely to have a thunderstorm and least likely to have a rainstorm. Neither event happens here every year.


The weather data here are long-term averages provided by the US National Centers for Environmental Information (NCEI). Temperature and precipitation are 1991-2020 normals while humidity and thunderstorms are 1961-1990 normals.

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