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.
This Afternoon
73°F
Rain
Rain and a slight chance of thunderstorms. Cloudy. High near 73, with temperatures falling to around 67 in the afternoon. South wind 18 to 23 mph, with gusts as high as 33 mph. Chance of precipitation is 100%.
7-day forecast for West Alton
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| This Afternoon | 73°F | Rain | 18 to 23 mph S | 98% |
| Tonight | 54°F | Rain | 9 to 18 mph S | 97% |
| Wednesday | 64°F | Chance Rain Showers then Mostly Cloudy | 9 to 15 mph W | 12% |
| Wednesday Night | 44°F | Partly Cloudy | 5 to 8 mph SW | 0% |
| Thursday | 66°F | Sunny | 6 to 12 mph W | 2% |
| Thursday Night | 44°F | Mostly Cloudy | 3 to 7 mph NW | 9% |
| Friday | 59°F | Mostly Cloudy | 6 to 12 mph NW | 5% |
| Friday Night | 39°F | Partly Cloudy | 2 to 8 mph N | 1% |
| Saturday | 57°F | Mostly Sunny | 5 mph NW | 0% |
| Saturday Night | 37°F | Partly Cloudy | 2 mph NW | 0% |
| Sunday | 63°F | Sunny | 2 to 8 mph W | 8% |
| Sunday Night | 37°F | Mostly Clear | 2 to 6 mph W | 4% |
| Monday | 67°F | Sunny | 2 to 8 mph SW | 2% |
| Monday Night | 41°F | Mostly Clear | 5 mph SW | 1% |
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
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St. Paul
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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 Nov 3, 2026.