Harman US

Lyndon, IL Weather & Growing Conditions

Today
81°F
Chance Showers And Thunderstorms
A chance of showers and thunderstorms before 1pm, then a chance of showers and thunderstorms between 1pm and 4pm, then a chance of showers and thunderstorms. Mostly cloudy, with a high near 81. Southeast wind around 10 mph. Chance of precipitation is 40%. New rainfall amounts between a quarter and half of an inch possible.

7-day forecast

WhenTempForecastWindPrecip
Today 81°F Chance Showers And Thunderstorms 10 mph SE 40%
Tonight 63°F Chance Showers And Thunderstorms then Showers And Thunderstorms 5 to 10 mph NW 89%
Sunday 70°F Rain Showers Likely 10 to 15 mph NE 71%
Sunday Night 56°F Chance Rain Showers 15 mph NE 40%
Monday 65°F Chance Rain Showers 15 mph NE 51%
Monday Night 51°F Chance Rain Showers 10 to 15 mph NE 39%
Tuesday 64°F Slight Chance Rain Showers then Partly Sunny 15 mph NE 17%
Tuesday Night 48°F Partly Cloudy 5 to 15 mph NE 8%
Wednesday 67°F Mostly Sunny 10 mph NE 1%
Wednesday Night 50°F Partly Cloudy 5 to 10 mph NE 1%
Thursday 69°F Mostly Sunny 5 mph NE 5%
Thursday Night 52°F Partly Cloudy 0 to 5 mph NE 5%
Friday 72°F Mostly Sunny 5 mph NE 4%
Friday Night 52°F Partly Cloudy 0 to 5 mph E 4%

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

Growing snapshot for Lyndon, IL

Last spring frost
Apr 26
First fall frost
Oct 13
Growing season
167 days
Hardiness zone
5b

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

Climate data from the nearest NOAA station, Morrison, Il (5 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.