Harman US

Johnston City, IL Weather & Growing Conditions

Today
63°F
Partly Sunny
Partly sunny, with a high near 63. West southwest wind 5 to 10 mph.

7-day forecast

WhenTempForecastWindPrecip
Today 63°F Partly Sunny 5 to 10 mph WSW 10%
Tonight 44°F Mostly Clear 3 mph WSW 0%
Thursday 69°F Sunny 3 to 8 mph WSW 0%
Thursday Night 45°F Partly Cloudy 2 mph WNW 1%
Friday 61°F Partly Sunny 3 to 12 mph NNW 0%
Friday Night 36°F Partly Cloudy 2 to 8 mph N 0%
Saturday 57°F Mostly Sunny 2 to 6 mph N 0%
Saturday Night 34°F Partly Cloudy 1 mph NNW 0%
Sunday 62°F Sunny 1 to 7 mph NW 0%
Sunday Night 34°F Clear 2 mph NW 1%
Monday 66°F Sunny 0 to 7 mph WSW 0%
Monday Night 38°F Clear 2 mph SW 1%
Tuesday 70°F Sunny 1 to 6 mph WSW 1%
Tuesday Night 41°F Mostly Clear 1 mph WNW 1%

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 Nov 4, 2026.