Seattle
Seattle / UW · Zone 8b · Urban core. Warmer than surrounding areas due to heat island effect.
Data through May 13, 2026
Season Progress
Cumulative GDD₃₂ year to date. Other stations shown faded for regional context.
Season vs. History
As of May 13, 2026, Seattle has accumulated 2062.8 GDD₃₂, which is 16% ahead of the 2020–2025 average of 1783.5 for this date. This season is tracking closest to 2025.
Cumulative GDD₃₂ by day of year. Current season (bold) against 2020–2025 individual years (faded) and their average (dashed).
Soil Temperature
Daily soil temperature at 2-inch depth. Bands: below 40°F (too cold), 40-50°F (cool-season), above 50°F (warm-season activation).
Frost Events
Every night the temperature dropped below 32°F. Color indicates severity: light (28-32°F), moderate (24-28°F), hard (<24°F).
Precipitation
Daily rainfall (bars) and cumulative total (bold line) for Seattle. Other stations shown faded.
Chill Hours
Cumulative hours below 45°F since January 1. Dashed lines show common fruit tree thresholds.
Dew Point & Disease Risk
Daily average dew point. Watch zone: 50-55°F. Active disease risk above 55°F.
Water Balance
Cumulative precipitation (solid) vs. evapotranspiration (dashed) for Seattle. When ET crosses above precipitation, start irrigating.
Sunshine Hours
7-day rolling average of daily sunshine. Other stations faded for comparison.
Monthly Summary
| Month | Low | High | Precip | Frost | Spray | GDD₃₂ | Sun hrs |
|---|---|---|---|---|---|---|---|
| Jan | 29.3° | 56.3° | 5.52" | 3 | 12 | 355.9 | 128.8 |
| Feb | 31.9° | 57.3° | 3.55" | 1 | 7 | 356 | 161.8 |
| Mar | 32.4° | 57.7° | 4.17" | 0 | 10 | 413.9 | 136.9 |
| Apr | 34.9° | 74.5° | 1.63" | 0 | 19 | 578.2 | 229 |
| May | 46.8° | 81.7° | 0.11" | 0 | 12 | 358.8 | 108.8 |
Other Stations
Data from the HortGuide station network via Open-Meteo. Your microclimate varies. Updated daily.