USA

Seattle weather in September

Weather in Seattle: September


	Average day temperature:	70.1°F
	Average night temperature:	56.7°F

	Number of sunny days:	14 days
	Day length:	11.7 - 13.4 hours

	Number of rainy days:	2 days
	Precipitation totals:	1.1 in.

more information

14 days
forecast

Seattle

weather in
October

Seattle

January
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September
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2024

2023

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112

Day temperature

Night temperature

The highest day temperature during September of 2024 was 86°F. At the same time the lowest night temperature was 49°F. Daily and nightly averages during September were 69.1°F and 56.7°F.

	Sunny days
	Partly cloudy days
	Cloudy days

37%

27%

37%

Number of sunny, partly cloudy and cloudy days in September is almost equal.

jan

feb

mar

apr

may

jun

jul

aug

sep

oct

nov

dec

0.0

0.5

0.9

1.4

1.8

2.3

2.8

3.2

2.2

1.9

1.8

1.0

1.3

2.0

1.9

1.8

2.7

2.2

1.9

1.8

1.1

1.0

1.3

2.0

1.9

1.8

2.7

Precipitation total value in Seattle in September is 1.1 in. Other months of the year show relatively similar values.

jan

feb

mar

apr

may

jun

jul

aug

sep

oct

nov

dec

0.0

1.0

1.9

2.9

3.9

4.8

5.8

6.8

7.7

5.0

5.4

4.9

4.6

5.1

4.9

5.6

5.4

5.0

5.4

4.9

4.6

5.1

4.9

5.6

5.4

5.0

The average wind speed value in September is 4.6 mph It makes September one of the least windy months of the year.

jan

feb

mar

apr

may

jun

jul

aug

sep

oct

nov

dec

0.0

2.0

3.9

5.9

7.9

9.8

11.8

13.8

2.0

2.8

5.0

9.7

11.5

8.9

6.7

5.5

3.9

2.8

2.7

2.0

2.8

5.0

7.0

9.7

11.5

8.9

6.7

5.5

3.9

2.8

2.7

This chart shows average number of hours during the day when sunlight can reach the ground. It depends on day length and cloudiness during the day. The average number of sunny hours in September is: 7.0.