Harman US

St. Louis, MO Weather & Growing Conditions

This Afternoon
99°F
Partly Sunny
Partly sunny, with a high near 99. Heat index values as high as 102. West wind around 7 mph.

7-day forecast

WhenTempForecastWindPrecip
This Afternoon 99°F Partly Sunny 7 mph W 1%
Tonight 75°F Partly Cloudy 6 mph S 1%
Sunday 94°F Mostly Sunny then Slight Chance Showers And Thunderstorms 6 mph W 17%
Sunday Night 69°F Chance Showers And Thunderstorms then Showers And Thunderstorms Likely 5 to 8 mph NE 71%
Monday 81°F Showers And Thunderstorms Likely 7 mph NE 71%
Monday Night 62°F Chance Showers And Thunderstorms 5 to 8 mph NE 48%
Tuesday 73°F Slight Chance Rain Showers then Mostly Cloudy 7 to 10 mph N 19%
Tuesday Night 57°F Mostly Cloudy 5 to 10 mph N 1%
Wednesday 74°F Mostly Sunny 8 mph N 0%
Wednesday Night 57°F Partly Cloudy 2 to 7 mph N 0%
Thursday 76°F Mostly Sunny 6 mph N 1%
Thursday Night 61°F Mostly Cloudy 5 mph NE 11%
Friday 79°F Slight Chance Rain Showers 2 to 6 mph NE 18%
Friday Night 61°F Slight Chance Rain Showers then Mostly Cloudy 6 mph NE 18%

Forecast source: National Weather Service (api.weather.gov). Updated through the day.

Growing snapshot for St. Louis, MO

Last spring frost
Apr 6
First fall frost
Oct 27
Growing season
203 days
Hardiness zone
7a

Explore more for St. Louis, MO: full frost dates · planting calendar · Missouri frost dates

Climate data from the nearest NOAA station, Cahokia, Il (3.2 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 20, 2026.