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Clarkson Valley, MO Weather & Growing Conditions

Local forecast, frost dates, hardiness zone and planting guidance for Clarkson Valley, a city in St. Louis County, Missouri.

Tonight
54°F
Rain
Rain and a slight chance of thunderstorms before 3am, then a chance of rain showers between 3am and 4am. Cloudy, with a low around 54. South wind 7 to 12 mph, with gusts as high as 25 mph. Chance of precipitation is 80%.

7-day forecast for Clarkson Valley

WhenTempForecastWindPrecip
Tonight 54°F Rain 7 to 12 mph S 79%
Wednesday 63°F Mostly Cloudy 6 to 13 mph W 3%
Wednesday Night 44°F Partly Cloudy 6 mph SW 0%
Thursday 66°F Sunny 6 to 9 mph W 2%
Thursday Night 44°F Mostly Cloudy 6 mph NW 9%
Friday 58°F Mostly Cloudy 8 mph NW 4%
Friday Night 40°F Mostly Cloudy 5 mph N 2%
Saturday 57°F Partly Sunny 3 mph NW 0%
Saturday Night 37°F Partly Cloudy 2 mph NW 2%
Sunday 63°F Sunny 2 to 6 mph W 9%
Sunday Night 37°F Mostly Clear 3 mph W 4%
Monday 67°F Sunny 6 mph SW 2%
Monday Night 42°F Mostly Clear 5 mph SW 1%
Tuesday 69°F Sunny 5 mph W 1%

Forecast source: National Weather Service (api.weather.gov) for Clarkson Valley (38.625, -90.593). Updated through the day.

Growing snapshot for Clarkson Valley

Last spring frost
Apr 4
First fall frost
Oct 29
Growing season
206 days
Hardiness zone
7a

More local growing data for Clarkson Valley: nearby ZIP 63011 weather · frost dates · planting calendar · Missouri frost dates

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Climate data from the nearest NOAA station, St Charles 7 Ssw, Mo (5.8 mi from Clarkson Valley). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 4, 2026.