Average Precipitation for Washington in September





The tables below give monthly averages for rainfall plus snowfall during September at cities, towns and parks in Washington.

Each place has a total for the amount of precipitation it usually receives this month. Most sites also have information on the number of days with wet weather. That includes the days when precipitation amounts to 0.01 inches (0.25 millimetres) or more.

The precipitation totals are averages based on weather data collected from 1981 to 2010 for the NOAA National Climatic Data Center.

You can jump to a separate table for each region of the state: Olympic Peninsula & West Coast, San Juan Islands & Puget Sound, Cascade Mountains and Eastern Washington.

Olympic Peninsula & West Coast

Average monthly precipitation in September
Days Place Inches Milli­metres
9 Aberdeen 2.5 64
10 Clearwater 4.3 109
11 Forks 4.0 102
Friday Harbor, San Juan Island 1.4 36
10 Grayland 2.6 65
12 Long Beach 2.6 66
7 Port Angeles 0.9 24

San Juan Islands, Puget Sound & South

September averages for total precipitation
Days Place Inches Milli­metres
7 Anacortes 1.5 39
10 Bellingham 1.8 45
8 Bremerton 1.6 39
9 Everett 2.0 50
9 Longview 2.1 52
6 Olga, Orcas Island 1.3 34
8 Olympia 1.7 43
8 Port Townsend 1.0 26
8 Seattle 1.3 33
7 Tacoma 1.3 33
8 Vancouver 1.6 41

Cascade Mountains

Average amount of rain and snow in September
Days Place Inches Milli­metres
10 Baker Lake Dam 4.2 107
10 Baring 4.6 116
Darrington 3.0 75
Mt Adams Ranger Station 1.1 28
10 Mt Rainier Paradise Ranger Station 4.7 120
10 Mud Mountain Lake Dam 2.8 72
9 Ross Dam 2.1 53
11 Stampede Pass 4.1 105

Eastern Washington State

Precipitation totals for September
Days Place Inches Milli­metres
8 Boundary Dam 1.4 36
3 Chelan 0.4 9
4 Coulee Dam 0.4 11
3 Kennewick 0.3 8
4 Leavenworth 0.7 17
5 Pullman 0.8 20
5 Spokane 0.7 17
4 Walla Walla 0.8 19
3 Wenatchee 0.3 9
4 Winthrop 0.4 11
3 Yakima 0.4 9
Reference

National Climatic Data Center. NOAA's 1981-2010 Climate Normals.

Washington Precipitation
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