St. John, IN Weather & Growing Conditions
Today
78°F
Showers And Thunderstorms then Showers And Thunderstorms Likely
Showers and thunderstorms before noon, then showers and thunderstorms likely. Cloudy. High near 78, with temperatures falling to around 76 in the afternoon. Southeast wind 5 to 10 mph. Chance of precipitation is 100%. New rainfall amounts between a half and three quarters of an inch possible.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 78°F | Showers And Thunderstorms then Showers And Thunderstorms Likely | 5 to 10 mph SE | 96% |
| Tonight | 64°F | Showers And Thunderstorms Likely then Showers And Thunderstorms | 5 mph S | 89% |
| Sunday | 70°F | Showers And Thunderstorms Likely | 5 to 15 mph NNE | 62% |
| Sunday Night | 54°F | Chance Showers And Thunderstorms | 10 to 15 mph NE | 41% |
| Monday | 65°F | Chance Rain Showers | 10 to 15 mph NE | 43% |
| Monday Night | 50°F | Chance Rain Showers then Mostly Cloudy | 10 to 15 mph NE | 28% |
| Tuesday | 64°F | Slight Chance Rain Showers | 10 to 15 mph NE | 16% |
| Tuesday Night | 51°F | Mostly Cloudy | 5 to 10 mph NE | 14% |
| Wednesday | 65°F | Partly Sunny | 5 to 10 mph NNE | 10% |
| Wednesday Night | 52°F | Mostly Cloudy | 5 to 10 mph NNE | 6% |
| Thursday | 67°F | Partly Sunny | 5 to 10 mph NNE | 3% |
| Thursday Night | 52°F | Mostly Cloudy | 5 to 10 mph NNE | 3% |
| Friday | 70°F | Mostly Sunny | 5 to 10 mph NE | 3% |
| Friday Night | 52°F | Partly Cloudy | 0 to 10 mph ENE | 2% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for St. John, IN
Last spring frost
Apr 23
First fall frost
Oct 20
Growing season
179 days
Hardiness zone
6a
Explore more for St. John, IN: full frost dates · planting calendar · Indiana frost dates
Climate data from the nearest NOAA station, Park Forest, Il (11.6 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.