Frontenac, MO Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Frontenac, a city in St. Louis County, Missouri.
Overnight
69°F
Clear
Clear, with a low around 69. East wind around 2 mph.
7-day forecast for Frontenac
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Overnight | 69°F | Clear | 2 mph E | 0% |
| Tuesday | 90°F | Sunny | 3 mph SE | 0% |
| Tuesday Night | 70°F | Mostly Clear | 5 mph SE | 0% |
| Wednesday | 91°F | Sunny | 6 mph S | 10% |
| Wednesday Night | 72°F | Slight Chance Showers And Thunderstorms | 7 mph S | 67% |
| Thursday | 88°F | Showers And Thunderstorms Likely | 5 mph S | 68% |
| Thursday Night | 71°F | Chance Showers And Thunderstorms | 5 mph SE | 30% |
| Friday | 88°F | Chance Showers And Thunderstorms | 3 mph SW | 30% |
| Friday Night | 72°F | Chance Showers And Thunderstorms | 3 mph S | 27% |
| Saturday | 90°F | Chance Showers And Thunderstorms then Mostly Sunny | 5 mph SW | 27% |
| Saturday Night | 73°F | Mostly Clear | 6 mph S | 7% |
| Sunday | 93°F | Sunny | 5 to 8 mph SW | 6% |
| Sunday Night | 75°F | Mostly Clear | 7 mph S | 5% |
| Monday | 95°F | Sunny | 8 mph SW | 5% |
Forecast source: National Weather Service (api.weather.gov) for Frontenac (38.630, -90.419). Updated through the day.
Growing snapshot for Frontenac
Last spring frost
Apr 4
First fall frost
Oct 29
Growing season
206 days
Hardiness zone
7a
More local growing data for Frontenac: nearby ZIP 63131 weather · frost dates · planting calendar · Missouri frost dates
Nearby towns & communities
Affton
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Bel-Nor
Bel-Ridge
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Bellefontaine Neighbors
Bellerive Acres
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Breckenridge Hills
Brentwood
Bridgeton
Calverton Park
Castle Point
Champ
Charlack
Chesterfield
Clarkson Valley
Clayton
Concord
Cool Valley
Country Club Hills
Country Life Acres
Crestwood
Creve Coeur
Crystal Lake Park
Dellwood
Des Peres
Edmundson
Climate data from the nearest NOAA station, St Charles 7 Ssw, Mo (6.5 mi from Frontenac). Frost dates are 1991–2020 averages, not a forecast. Page updated Aug 4, 2026.