Johnston City, IL Weather & Growing Conditions
Today
89°F
Sunny
Sunny, with a high near 89. East northeast wind 0 to 3 mph.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 89°F | Sunny | 0 to 3 mph ENE | 0% |
| Tonight | 64°F | Mostly Clear | 0 to 3 mph E | 0% |
| Wednesday | 91°F | Sunny | 0 to 3 mph SSW | 0% |
| Wednesday Night | 70°F | Mostly Clear | 2 mph S | 3% |
| Thursday | 91°F | Chance Showers And Thunderstorms | 2 to 7 mph SSW | 26% |
| Thursday Night | 71°F | Showers And Thunderstorms Likely | 1 to 6 mph S | 58% |
| Friday | 90°F | Showers And Thunderstorms Likely then Chance Showers And Thunderstorms | 2 to 7 mph SW | 58% |
| Friday Night | 70°F | Chance Showers And Thunderstorms | 3 mph SSW | 39% |
| Saturday | 90°F | Chance Showers And Thunderstorms | 2 to 6 mph SSW | 39% |
| Saturday Night | 71°F | Slight Chance Showers And Thunderstorms then Partly Cloudy | 1 to 5 mph SSW | 16% |
| Sunday | 93°F | Sunny | 3 to 10 mph SSW | 7% |
| Sunday Night | 73°F | Mostly Clear | 5 to 10 mph SSW | 5% |
| Monday | 94°F | Sunny | 5 to 10 mph SSW | 5% |
| Monday Night | 74°F | Mostly Clear | 6 to 9 mph SSW | 6% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for Johnston City, IL
Last spring frost
Apr 4
First fall frost
Oct 28
Growing season
206 days
Hardiness zone
7a
Explore more for Johnston City, IL: full frost dates · planting calendar · Illinois frost dates
Climate data from the nearest NOAA station, Benton 2 N, Il (14.4 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Aug 4, 2026.