Barnhart, MO Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Barnhart, a community in Jefferson County, Missouri.
This Afternoon
98°F
Chance Showers And Thunderstorms
A chance of showers and thunderstorms. Sunny, with a high near 98. Heat index values as high as 106. South wind around 2 mph. Chance of precipitation is 30%.
7-day forecast for Barnhart
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| This Afternoon | 98°F | Chance Showers And Thunderstorms | 2 mph S | 26% |
| Tonight | 72°F | Slight Chance Showers And Thunderstorms then Mostly Clear | 3 mph SE | 23% |
| Saturday | 98°F | Mostly Sunny | 6 mph SW | 5% |
| Saturday Night | 73°F | Partly Cloudy | 5 mph SW | 0% |
| Sunday | 95°F | Mostly Sunny then Slight Chance Showers And Thunderstorms | 5 mph W | 15% |
| Sunday Night | 67°F | Chance Showers And Thunderstorms then Showers And Thunderstorms Likely | 5 mph N | 56% |
| Monday | 82°F | Showers And Thunderstorms Likely | 6 mph N | 67% |
| Monday Night | 60°F | Showers And Thunderstorms Likely then Slight Chance Showers And Thunderstorms | 7 mph N | 67% |
| Tuesday | 73°F | Slight Chance Rain Showers then Mostly Cloudy | 8 mph N | 20% |
| Tuesday Night | 54°F | Mostly Cloudy | 7 mph N | 7% |
| Wednesday | 75°F | Mostly Sunny | 6 mph N | 2% |
| Wednesday Night | 55°F | Partly Cloudy | 5 mph N | 2% |
| Thursday | 76°F | Mostly Sunny | 2 to 6 mph N | 3% |
| Thursday Night | 57°F | Partly Cloudy | 5 mph N | 3% |
Forecast source: National Weather Service (api.weather.gov) for Barnhart (38.337, -90.403). Updated through the day.
Growing snapshot for Barnhart
Last spring frost
Apr 9
First fall frost
Oct 26
Growing season
197 days
Hardiness zone
7a
More local growing data for Barnhart: nearby ZIP 63053 weather · frost dates · planting calendar · Missouri frost dates
Nearby towns & communities
Arnold
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Herculaneum
High Ridge
Hillsboro
Horine
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Kimmswick
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Olympian Village
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Peaceful Village
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Scotsdale
Summer Set
Climate data from the nearest NOAA station, Festus, Mo (9.4 mi from Barnhart). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.