West Alton, MO Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for West Alton, a city in St. Charles County, Missouri.
Today
89°F
Sunny
Sunny, with a high near 89. Southeast wind around 5 mph.
7-day forecast for West Alton
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 89°F | Sunny | 5 mph SE | 0% |
| Tonight | 69°F | Mostly Clear | 2 to 6 mph SE | 0% |
| Wednesday | 91°F | Sunny | 2 to 7 mph S | 12% |
| Wednesday Night | 72°F | Chance Showers And Thunderstorms | 7 mph S | 73% |
| Thursday | 87°F | Showers And Thunderstorms Likely | 6 mph SW | 73% |
| Thursday Night | 70°F | Chance Showers And Thunderstorms | 1 to 5 mph SE | 29% |
| Friday | 87°F | Chance Showers And Thunderstorms | 5 mph SW | 29% |
| Friday Night | 71°F | Chance Showers And Thunderstorms | 1 to 5 mph S | 31% |
| Saturday | 90°F | Chance Showers And Thunderstorms then Mostly Sunny | 2 to 6 mph S | 31% |
| Saturday Night | 73°F | Mostly Clear | 6 mph S | 6% |
| Sunday | 92°F | Sunny | 5 to 9 mph S | 6% |
| Sunday Night | 75°F | Mostly Clear | 8 mph S | 5% |
| Monday | 94°F | Mostly Sunny | 6 to 9 mph SW | 5% |
| Monday Night | 75°F | Slight Chance Showers And Thunderstorms | 8 mph SW | 17% |
Forecast source: National Weather Service (api.weather.gov) for West Alton (38.863, -90.204). Updated through the day.
Growing snapshot for West Alton
Last spring frost
Apr 4
First fall frost
Nov 5
Growing season
214 days
Hardiness zone
7a
More local growing data for West Alton: nearby ZIP 63386 weather · frost dates · planting calendar · Missouri frost dates
Nearby towns & communities
Augusta
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O'Fallon
St. Paul
St. Peters
Weldon Spring
Weldon Spring Heights
Wentzville
Climate data from the nearest NOAA station, Alton - Melvin Price L&D, Il (3.8 mi from West Alton). Frost dates are 1991–2020 averages, not a forecast. Page updated Aug 4, 2026.