Frontenac, MO Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Frontenac, a city in St. Louis County, Missouri.
This Afternoon
59°F
Mostly Cloudy
Mostly cloudy, with a high near 59. West wind around 8 mph.
7-day forecast for Frontenac
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| This Afternoon | 59°F | Mostly Cloudy | 8 mph W | 0% |
| Tonight | 46°F | Partly Cloudy | 7 mph SW | 0% |
| Thursday | 62°F | Mostly Sunny | 6 to 10 mph W | 9% |
| Thursday Night | 46°F | Isolated Rain Showers then Mostly Cloudy | 7 mph NW | 16% |
| Friday | 54°F | Partly Sunny | 9 mph N | 5% |
| Friday Night | 35°F | Mostly Clear | 2 to 6 mph N | 0% |
| Saturday | 54°F | Mostly Sunny | 2 mph N | 0% |
| Saturday Night | 35°F | Mostly Clear | 2 mph NW | 0% |
| Sunday | 59°F | Sunny | 3 mph W | 0% |
| Sunday Night | 38°F | Mostly Clear | 1 mph W | 0% |
| Monday | 65°F | Sunny | 3 mph SW | 0% |
| Monday Night | 42°F | Clear | 3 mph SW | 1% |
| Tuesday | 66°F | Sunny | 3 mph W | 3% |
| Tuesday Night | 44°F | Mostly Clear | 1 mph NW | 3% |
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
Ballwin
Bel-Nor
Bel-Ridge
Bella Villa
Bellefontaine Neighbors
Bellerive Acres
Berkeley
Beverly Hills
Black Jack
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 Nov 5, 2026.