Troy, IL Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Troy, a city in Madison County, Illinois.
Today
97°F
Partly Sunny
Partly sunny, with a high near 97. Heat index values as high as 101. Southwest wind around 8 mph.
7-day forecast for Troy
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 97°F | Partly Sunny | 8 mph SW | 3% |
| Tonight | 73°F | Partly Cloudy | 5 mph SW | 3% |
| Sunday | 93°F | Chance Rain Showers then Slight Chance Showers And Thunderstorms | 3 to 8 mph W | 26% |
| Sunday Night | 67°F | Showers And Thunderstorms Likely | 7 to 12 mph NE | 58% |
| Monday | 78°F | Showers And Thunderstorms Likely | 7 to 13 mph NE | 65% |
| Monday Night | 59°F | Showers And Thunderstorms Likely then Slight Chance Showers And Thunderstorms | 8 to 13 mph NE | 55% |
| Tuesday | 71°F | Slight Chance Rain Showers then Partly Sunny | 13 mph NE | 19% |
| Tuesday Night | 54°F | Mostly Cloudy | 6 to 13 mph N | 7% |
| Wednesday | 74°F | Mostly Sunny | 8 to 12 mph N | 2% |
| Wednesday Night | 55°F | Partly Cloudy | 3 to 10 mph N | 0% |
| Thursday | 76°F | Mostly Sunny | 3 to 9 mph N | 1% |
| Thursday Night | 57°F | Partly Cloudy | 3 to 9 mph NE | 3% |
| Friday | 78°F | Mostly Sunny | 3 to 9 mph NE | 5% |
| Friday Night | 57°F | Partly Cloudy | 3 to 8 mph NE | 5% |
Forecast source: National Weather Service (api.weather.gov) for Troy (38.740, -89.883). Updated through the day.
Growing snapshot for Troy
Last spring frost
Apr 12
First fall frost
Oct 20
Growing season
189 days
Hardiness zone
7a
More local growing data for Troy: nearby ZIP 62294 weather · frost dates · planting calendar · Illinois frost dates
Nearby towns & communities
Alhambra
Alton
Bethalto
Collinsville
East Alton
Edwardsville
Glen Carbon
Godfrey
Granite City
Grantfork
Hamel
Hartford
Highland
Holiday Shores
Livingston
Madison
Marine
Maryville
Mitchell
Moro
New Douglas
Pontoon Beach
Prairietown
Rosewood Heights
Roxana
South Roxana
St. Jacob
Venice
Williamson
Wood River
Climate data from the nearest NOAA station, Belleville Siu Rsch, Il (12.7 mi from Troy). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.