Seattle has a temperate marine climate (Köppen Csb) shaped by Puget Sound and the Olympic and Cascade mountain ranges. The city gets about 963mm (38 inches) of rain annually, less than New York (1,268mm) or Miami (1,570mm), but the drizzle falls over 150 days a year, mostly as persistent light rain from November through March. Summers are dry, with only 18mm of rain in July, while November is the wettest month at 152mm. Snow is rare in the city (average 13cm per year), though the Cascade passes an hour east receive heavy snow for skiing. Also see our best time to visit Seattle for more planning information.
| Month | Avg High | Avg Low | Rain (mm) | Rain Days | Sun (hrs) |
|---|---|---|---|---|---|
| January | 8°C / 47°F | 3°C / 37°F | 142 | 19 | 70 |
| February | 10°C / 51°F | 3°C / 38°F | 98 | 16 | 95 |
| March | 12°C / 54°F | 5°C / 40°F | 100 | 17 | 150 |
| April | 15°C / 59°F | 7°C / 44°F | 70 | 14 | 200 |
| May | 18°C / 65°F | 10°C / 50°F | 50 | 12 | 250 |
| June | 21°C / 70°F | 13°C / 55°F | 40 | 9 | 270 |
| July | 24°C / 76°F | 15°C / 58°F | 18 | 5 | 310 |
| August | 24°C / 76°F | 15°C / 59°F | 25 | 6 | 280 |
| September | 21°C / 70°F | 12°C / 54°F | 40 | 8 | 220 |
| October | 15°C / 60°F | 9°C / 48°F | 88 | 13 | 140 |
| November | 11°C / 51°F | 5°C / 42°F | 152 | 19 | 70 |
| December | 8°C / 46°F | 3°C / 37°F | 140 | 19 | 55 |
Seattle Weather by Month: Winter (December to February)
Winter highs hover around 8-10°C (46-51°F) with lows near 3°C (37°F). December and January are the darkest months with only 55-70 hours of sunshine and 19 rain days each. Snow falls 2-3 times per winter but rarely sticks more than a day in the city center. The Cascade passes (Snoqualmie Pass on I-90, Stevens Pass on US-2) get heavy snow for skiing, about 60-90 minutes east of downtown. November is actually the wettest month at 152mm, so pack a waterproof shell with a hood rather than an umbrella. Winter hotel rates drop 30-40% from July peaks. Also see our things to do in Seattle for more planning information.
Seattle Weather by Month: Spring (March to May)
Spring is a slow warm-up. March starts cool and damp at 12°C (54°F) with 100mm of rain, but by May you get 18°C (65°F) with only 50mm. The cherry blossoms at the University of Washington Quad peak in late March to early April and draw crowds comparable to DC’s Tidal Basin. April is the pivot month: rain drops to 70mm across 14 days and sunshine doubles from March’s 150 hours to 200. May is when outdoor patios fill and farmers markets reopen. Pack layers since mornings can be 8°C (46°F) when afternoons hit 18°C (65°F). Also see our Seattle events and festivals for more planning information.
Seattle Weather by Month: Summer (June to August)
This is the season locals endure the other nine months for. July and August both average 24°C (76°F) with lows around 15°C (58-59°F). July gets just 5 rain days totaling 18mm, making it the driest month. Sunshine peaks at 310 hours in July. The marine layer sometimes brings morning clouds that burn off by 11am. Most Seattle buildings lack air conditioning because summer heat rarely exceeds 32°C (90°F), but heat waves happen: the city hit 42°C (108°F) during the June 2021 heat dome. Book hotels 2-3 months ahead for July and August stays. Also see our Seattle neighborhoods guide for more planning information.
Seattle Weather by Month: Autumn (September to November)
September often delivers the best weather: 21°C (70°F) with only 40mm of rain and 220 hours of sunshine. Tourist crowds thin after Labor Day and hotel rates drop 20-30% from summer peaks. October cools to 15°C (60°F) with 88mm of rain; fall foliage in the Washington Park Arboretum and Discovery Park peaks mid-month. By November, the rains return at full force with 152mm and 19 rain days, while highs drop to 11°C (51°F). Waterfront areas like Ballard and Magnolia get more autumn wind than inland Capitol Hill. Also see our where to stay in Seattle for more planning information. Also see our Seattle travel tips for more planning information.
