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Soil Temperature in Washington

The current average 2-inch soil temperature across Washington is 57°F. Readings range from 53°F to 62°F, from 5 USDA and NOAA monitoring stations. Soil across Washington is right at the seasonal normal of 56°F for early October, based on 5 of 5 stations with historical records. Washington spans USDA hardiness zones 6b to 9a, cool-season grass country. Last updated September 30, 2026.

Current Planting Conditions

Prime fall conditions across Washington with soil averaging 57°F at 2 inches. This is the best seeding window of the year for tall fescue and Kentucky bluegrass, and the main fall feeding window for cool-season lawns.

Best Time to Plant Grass Seed in Washington

Cool-season · fall window
August 22
August 1 (coolest parts) to September 15 (warmest)

For cool-season lawns (fescue, bluegrass, ryegrass), fall is the best time to plant grass seed in Washington, with spring the second choice: fall seedlings face less weed competition and mature before summer heat. The window opens as 2-inch soil falls back through 70°F, and germination slows sharply once soil drops below 50°F, typically around October 22.

Cool-season · spring window
April 25
April 6 (warmest parts) to May 2 (coolest)

Spring is the second choice: the window opens when soil first holds 50°F and narrows as soil passes 65°F, typically by June 25.

RegionTypical spring window opensTypical fall window opensStations
Eastern WashingtonMay 2August 222
Central WashingtonApril 18—3

Fall seeding also needs a stop date: new seedlings want about six weeks of growth before frost arrives. Your city page estimates the last safe seeding date from its nearest station: see when to plant in Seattle, when to plant in Tacoma or when to plant in Spokane. Readings current through September 30, 2026: Washington averages 57°F at 2 inches right now; the Current Planting Conditions section above reads that number against the season.

Typical dates are computed from historical 2-inch soil temperature averages at 5 monitoring stations in Washington; your own window depends on your nearest station's readings.

Average Soil Temperature by Month in Washington

Historical 2-inch soil temperature normals for Washington: the median across 5 in-state stations with multi-year records. Any given year runs ahead of or behind these values; the live average at the top of this page shows where this year stands.

MonthAverage 2-inch soil temperature
January34°F
February35°F
March40°F
April47°F
May55°F
June63°F
July68°F
August67°F
September62°F
October51°F
November39°F
December35°F

Shaded spring cells fall in the 50°F to 55°F pre-emergent window at 2-inch depth. The highlighted row is the current month.

Grass Seed Germination in Washington

Grass seed germination

Grass seed germination temperatures across Washington. Soil warmth varies by location, so check a city page for the live reading and what germinates there now.

Grass speciesSeeding soil temp (2 in)Days
Kentucky bluegrass60–70°F14-30
Tall fescue60–70°F7-12
Perennial ryegrass60–70°F5-10
Fine fescue60–70°F7-14
Bermudagrass75–90°F10-30

Monitoring Stations in Washington (5)

For root-zone timing (fertilizer, aeration, weed control), see the 4-inch soil temperature for Washington. For accumulated-heat timing, see growing degree days for Washington. For how wet the ground is versus normal, see soil moisture for Washington. See the Washington soil temperature map for the full station view.

Map of current soil temperatures across Washington at 4-inch depth, interpolated from USDA SCAN and NOAA USCRN stations

Interpolated from the latest 4-inch readings and refreshed daily.

Station2" TempLast Reading
Lind #1 (Adams)62°F2026-09-30
Cook Farm Field D (Whitman)53°F2026-09-30
Spokane 17 SSW57°F2026-09-30
Darrington 21 NNE55°F2026-09-30
Quinault 4 NE57°F2026-09-30

Soil Temperature by Region in Washington

Current 2-inch readings grouped along Washington's east-to-west axis. Regional spread matters for timing: the warm end of the state can open an application window a week or more before the cool end.

RegionAvg 2" TempRangeStations
Eastern Washington (Whitman County)55°F53–57°F2
Central Washington (Adams County)58°F55–62°F3

Cities in Washington (40)

Cities in Washington with current soil temperature readings
CityZIPCurrent Temp
Auburn9800157°F
Bellevue9800455°F
Bellingham9822555°F
Blaine9823055°F
Bothell9801155°F
Bremerton9831057°F
Edmonds9802055°F
Everett9820155°F
Federal Way9800357°F
Gig Harbor9832957°F
Issaquah9802755°F
Kennewick9933662°F
Kent9803057°F
Kirkland9803355°F
Lacey9850357°F
Lakewood9843957°F
Lynnwood9803655°F
Marysville9827055°F
Mount Vernon9827355°F
Oak Harbor9827755°F
Olympia9850157°F
Pasco9930162°F
Port Angeles9836257°F
Port Orchard9836657°F
Pullman9916353°F
Puyallup9837157°F
Redmond9805255°F
Renton9805557°F
Richland9935262°F
Sammamish9807455°F
Seattle9810157°F
Silverdale9831557°F
Snohomish9829055°F
Spokane9920157°F
Sumner9835257°F
Tacoma9840157°F
Vancouver9866064°F
Wenatchee9880162°F
Woodinville9807255°F
Yakima9890162°F

Lawn Care Timing Guides for Washington

Soil Temperature FAQ for Washington

What is the current soil temperature in Washington?

The current average 2-inch soil temperature across Washington is 57°F. Readings range from 53°F to 62°F depending on location and elevation, from 5 USDA and NOAA monitoring stations. Soil across Washington is right at the seasonal normal of 56°F for early October, based on 5 of 5 stations with historical records.

When should I apply pre-emergent in Washington?

Apply pre-emergent herbicide when soil at 2 inches reaches 55°F for several consecutive days. Timing varies across Washington, so check your city's page for station-specific readings and the pre-emergent timing recommendation.

When can I plant grass seed in Washington?

Washington spans USDA hardiness zones 6b to 9a, cool-season grass country. For cool-season grasses (fescue, bluegrass), the fall window typically opens around August 22 and the spring window around April 25, based on historical 2-inch soil temperature averages at 5 in-state stations. Timing varies by location, so check your city's planting window for the dates specific to your area.