Harman US

Bethalto, IL Weather & Growing Conditions

Overnight
54°F
Chance Light Rain
A chance of rain before 3am, then a slight chance of drizzle. Mostly cloudy, with a low around 54. Southwest wind around 12 mph, with gusts as high as 21 mph. Chance of precipitation is 40%.

7-day forecast

WhenTempForecastWindPrecip
Overnight 54°F Chance Light Rain 12 mph SW 42%
Wednesday 62°F Slight Chance Drizzle then Mostly Cloudy 9 to 15 mph W 12%
Wednesday Night 44°F Partly Cloudy 5 to 8 mph W 0%
Thursday 64°F Sunny 6 to 13 mph W 2%
Thursday Night 43°F Mostly Cloudy 6 mph NW 9%
Friday 58°F Mostly Cloudy 6 to 10 mph NW 5%
Friday Night 38°F Partly Cloudy 2 to 8 mph N 1%
Saturday 56°F Mostly Sunny 5 mph NW 0%
Saturday Night 35°F Partly Cloudy 2 mph NW 1%
Sunday 62°F Sunny 2 to 8 mph W 7%
Sunday Night 35°F Mostly Clear 5 mph W 4%
Monday 66°F Sunny 2 to 8 mph SW 2%
Monday Night 40°F Mostly Clear 5 mph SW 1%
Tuesday 69°F Sunny 3 to 7 mph W 0%

Forecast source: National Weather Service (api.weather.gov). Updated through the day.

Growing snapshot for Bethalto, IL

Last spring frost
Apr 4
First fall frost
Nov 5
Growing season
214 days
Hardiness zone
7a

Explore more for Bethalto, IL: full frost dates · planting calendar · Illinois frost dates

Climate data from the nearest NOAA station, Alton - Melvin Price L&D, Il (4.9 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 4, 2026.