Seattle Weather by Month
| Month | High / Low °F (°C) | Rainy days | Rain (in) |
|---|---|---|---|
| January | 48 (8.9) / 37.7 (3.2) | 18.7 | 5.78 |
| February | 50.3 (10.2) / 37.7 (3.2) | 15.9 | 3.76 |
| March | 54.2 (12.3) / 39.9 (4.4) | 17.1 | 4.17 |
| April | 59.3 (15.2) / 43.3 (6.3) | 15 | 3.18 |
| May | 66.3 (19.1) / 48.7 (9.3) | 11.3 | 1.88 |
| June | 71.1 (21.7) / 53 (11.7) | 9.2 | 1.45 |
| July | 77.4 (25.2) / 56.8 (13.8) | 4.7 | 0.60 |
| August | 77.6 (25.3) / 57.2 (14.0) | 4.9 | 0.97 |
| September | 71.6 (22.0) / 53.6 (12.0) | 8.3 | 1.61 |
| October | 60.5 (15.8) / 47 (8.3) | 14.3 | 3.91 |
| November | 52.1 (11.2) / 40.9 (4.9) | 18.4 | 6.31 |
| December | 47 (8.3) / 37.1 (2.8) | 18.4 | 5.72 |
A month-by-month planning table for Seattle built on the NOAA 1991-2020 climate normals recorded at Seattle-Tacoma International Airport - the official 30-year averages, not a forecast. Pick any month for the typical high and low in Fahrenheit and Celsius, how many days usually see rain, and how much rain actually falls.
The numbers behind the umbrella reputation are stranger than the stereotype: Seattle averages 156 rain days a year - among the most in America - yet only 39.34 inches of rain, less than Houston, New Orleans or Miami gets. The rain is a fine, patient drizzle. And July, the locals' reward, is nearly Mediterranean: 77.4/56.8 F, 4.7 rain days, 0.60 inches.
How to use
- Pick your month from the dropdown.
- Read the typical high/low in F and C, rain days and monthly rainfall, plus the packing line.
- Cross-check the full 12-month table below when your dates are flexible.
Frequently asked questions
Does it really rain all the time in Seattle?
It drizzles more than it pours: 156 days a year see measurable rain - a top-five count - but the annual total is just 39.34 inches, roughly a third of New Orleans' 63 inches and less than Miami or New York. Most rain days deliver a few hundredths of an inch; all-day soakers are rare.
What was the Seattle heat dome?
The June 2021 Pacific Northwest heat dome pushed Sea-Tac to 108 F - an all-time record that beat the previous mark by three degrees and turned the typically air-conditioning-free city into a heat emergency. A typical June runs 71.1/53.0 F; 108 is roughly a 37-degree departure from normal.
When is the best time to visit Seattle?
July and August, and it is not close: 77.4 and 77.6 F highs, 4.7-4.9 rain days, under an inch of rain each - the dry, long-light stretch locals guard jealously. September (71.6/53.6 F, 8.3 rain days) is the quiet runner-up before the October rains resume.
Does it snow in Seattle?
Rarely, and lightly: Sea-Tac's 1991-2020 normals put annual snowfall in the low single digits of inches, and a decent snow - an inch or two - is enough to fold the hills into gridlock because the city owns few plows. Cold snaps here usually mean 20s F, not the 0 F record from January 1950.
Why are Seattle winters so dark?
Latitude plus cloud: at 47.6 degrees north, December daylight lasts about 8.5 hours, and November through January average 18-19 rain days a month, which keeps the ceiling grey for weeks. The temperature itself stays mild (47/37 F in December) - the season is dark and damp, not frigid.
How do these normals compare with a forecast?
Normals are 30-year averages - an individual week can run 10 degrees warm or cold, and a sunny week in January happens. Use the table to pick dates and pack, then check a forecast about a week before you travel.