St. John, WA Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for St. John, a town in Whitman County, Washington.
Today
87°F
Areas Of Smoke then Haze
Areas of smoke before 8am, then haze and areas of smoke between 8am and 9am, then smoke and haze between 9am and 10am, then haze and areas of smoke. Sunny, with a high near 87. Northeast wind around 5 mph.
7-day forecast for St. John
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 87°F | Areas Of Smoke then Haze | 5 mph NE | 0% |
| Tonight | 49°F | Haze | 3 mph NE | 0% |
| Wednesday | 93°F | Patchy Smoke | 3 mph SE | 0% |
| Wednesday Night | 52°F | Areas Of Smoke then Clear | 3 mph S | 0% |
| Thursday | 98°F | Sunny | 6 mph S | 0% |
| Thursday Night | 57°F | Mostly Clear | 1 to 5 mph S | 0% |
| Friday | 96°F | Sunny | 5 to 12 mph SW | 0% |
| Friday Night | 57°F | Mostly Clear | 3 to 10 mph SW | 0% |
| Saturday | 92°F | Sunny | 5 to 10 mph SW | 0% |
| Saturday Night | 55°F | Mostly Clear | 3 to 9 mph SW | 0% |
| Sunday | 87°F | Sunny | 6 to 10 mph SW | 0% |
| Sunday Night | 52°F | Mostly Clear | 3 to 8 mph S | 0% |
| Monday | 86°F | Sunny | 7 mph SW | 0% |
| Monday Night | 51°F | Mostly Clear | 2 to 6 mph S | 0% |
Forecast source: National Weather Service (api.weather.gov) for St. John (47.091, -117.589). Updated through the day.
Growing snapshot for St. John
Last spring frost
Apr 29
First fall frost
Oct 4
Growing season
161 days
Hardiness zone
6b
More local growing data for St. John: nearby ZIP 99171 weather · frost dates · planting calendar · Washington frost dates
Nearby towns & communities
Albion
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Clarkston Heights-Vineland
Colfax
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Endicott
Farmington
Garfield
LaCrosse
Lamont
Malden
Oakesdale
Palouse
Pullman
Rosalia
Steptoe
Tekoa
Uniontown
West Clarkston-Highland
Climate data from the nearest NOAA station, St John, Wa (3.1 mi from St. John). Frost dates are 1991–2020 averages, not a forecast. Page updated Aug 4, 2026.