Weldon Spring, MO Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Weldon Spring, a city in St. Charles County, Missouri.
Tonight
73°F
Partly Cloudy
Partly cloudy, with a low around 73. South wind 1 to 5 mph.
7-day forecast for Weldon Spring
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Tonight | 73°F | Partly Cloudy | 1 to 5 mph S | 11% |
| Saturday | 96°F | Mostly Sunny | 3 to 7 mph SW | 5% |
| Saturday Night | 72°F | Partly Cloudy | 5 mph SW | 4% |
| Sunday | 91°F | Chance Rain Showers then Chance Showers And Thunderstorms | 5 mph W | 28% |
| Sunday Night | 66°F | Chance Showers And Thunderstorms then Showers And Thunderstorms Likely | 6 mph N | 65% |
| Monday | 77°F | Showers And Thunderstorms Likely | 7 mph N | 69% |
| Monday Night | 59°F | Showers And Thunderstorms Likely | 8 mph N | 69% |
| Tuesday | 70°F | Slight Chance Rain Showers then Mostly Cloudy | 9 mph N | 23% |
| Tuesday Night | 54°F | Mostly Cloudy | 3 to 8 mph N | 5% |
| Wednesday | 73°F | Mostly Sunny | 6 mph N | 1% |
| Wednesday Night | 55°F | Partly Cloudy | 5 mph N | 1% |
| Thursday | 74°F | Mostly Sunny | 2 to 6 mph N | 3% |
| Thursday Night | 57°F | Partly Cloudy | 5 mph NE | 3% |
| Friday | 75°F | Mostly Sunny | 5 mph NE | 8% |
Forecast source: National Weather Service (api.weather.gov) for Weldon Spring (38.709, -90.653). Updated through the day.
Growing snapshot for Weldon Spring
Last spring frost
Apr 10
First fall frost
Oct 26
Growing season
199 days
Hardiness zone
6b
More local growing data for Weldon Spring: nearby ZIP 63304 weather · frost dates · planting calendar · Missouri frost dates
Nearby towns & communities
Augusta
Cottleville
Dardenne Prairie
Defiance
Flint Hill
Foristell
Josephville
Lake St. Louis
New Melle
O'Fallon
St. Paul
St. Peters
Weldon Spring Heights
Wentzville
West Alton
Climate data from the nearest NOAA station, Weldon Spring Nws, Mo (0.5 mi from Weldon Spring). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.