Average Precipitation for Washington in May





The tables below give monthly averages for rainfall plus snowfall during May 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 May
Days Place Inches Milli­metres
15 Aberdeen 3.8 96
15 Clearwater 5.6 142
17 Forks 5.8 147
Friday Harbor, San Juan Island 1.5 37
15 Grayland 3.6 91
17 Long Beach 3.8 97
10 Port Angeles 1.1 29

San Juan Islands, Puget Sound & South

May averages for total precipitation
Days Place Inches Milli­metres
11 Anacortes 1.9 48
13 Bellingham 2.5 63
13 Bremerton 2.5 62
13 Everett 2.7 68
14 Longview 3.2 81
9 Olga, Orcas Island 1.8 46
13 Olympia 2.3 59
12 Port Townsend 1.7 43
12 Seattle 2.0 51
11 Tacoma 2.1 54
15 Vancouver 2.7 69

Cascade Mountains

Average amount of rain and snow in May
Days Place Inches Milli­metres
15 Baker Lake Dam 5.1 130
17 Baring 5.6 141
Darrington 4.0 102
Mt Adams Ranger Station 1.7 42
15 Mt Rainier Paradise Ranger Station 5.9 150
17 Mud Mountain Lake Dam 4.8 122
12 Ross Dam 2.1 53
17 Stampede Pass 4.3 109

Eastern Washington State

Precipitation totals for May
Days Place Inches Milli­metres
14 Boundary Dam 2.7 69
6 Chelan 1.0 25
9 Coulee Dam 1.2 29
6 Kennewick 0.6 16
6 Leavenworth 1.1 27
10 Pullman 1.8 46
10 Spokane 1.6 41
10 Walla Walla 2.1 54
5 Wenatchee 0.6 14
8 Winthrop 1.1 28
6 Yakima 0.6 15
Reference

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

Washington Precipitation
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