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
| 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
| 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
| 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
| 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.