Seattle

Seattle / UW · Zone 8b · Urban core. Warmer than surrounding areas due to heat island effect.

Data through March 13, 2026

Most accumulated heat (GDD) in the network Lowest chill accumulation 8% above network average on GDD
GDD₃₂ YTD
876.7
Soil Temp
38.1°F
Chill Hours
993
Precip YTD
11.79"
Frost Nights
4
Spray Days
21

Season Progress

Cumulative GDD₃₂ year to date. Other stations shown faded for regional context.

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).

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 Snow Frost Spray GDD₃₂ Sun hrs
Jan 29.3° 56.3° 5.52" 0.8" 3 12 355.9 128.8
Feb 31.9° 57.3° 3.55" 2.1" 1 7 356 161.8
Mar 32.5° 56.1° 2.72" 1.5" 0 2 164.8 41.3

Other Stations

Olympia 810.1 GDD₃₂ · 15.08" precip Bellingham 808.3 GDD₃₂ · 15.58" precip Kent 798.1 GDD₃₂ · 12.85" precip Sequim 789.8 GDD₃₂ · 11.77" precip Tacoma 785 GDD₃₂ · 14.69" precip

Data from the HortGuide station network via Open-Meteo. Your microclimate varies. Updated daily.