Harman US

Crystal Lake, IL Weather & Growing Conditions

This Afternoon
69°F
Rain Showers Likely
Rain showers likely. Mostly cloudy. High near 69, with temperatures falling to around 65 in the afternoon. South wind around 15 mph, with gusts as high as 30 mph. Chance of precipitation is 70%. New rainfall amounts less than a tenth of an inch possible.

7-day forecast

WhenTempForecastWindPrecip
This Afternoon 69°F Rain Showers Likely 15 mph S 69%
Tonight 59°F Rain Showers 15 mph S 80%
Wednesday 62°F Rain Showers Likely 15 mph SSW 59%
Wednesday Night 47°F Slight Chance Rain Showers 15 mph SW 23%
Thursday 55°F Chance Rain Showers 10 to 15 mph WSW 45%
Thursday Night 41°F Chance Rain Showers 5 to 10 mph NW 50%
Friday 51°F Slight Chance Rain Showers 10 to 15 mph N 23%
Friday Night 34°F Mostly Cloudy 0 to 5 mph NNW 3%
Saturday 52°F Mostly Sunny 0 to 5 mph WNW 5%
Saturday Night 34°F Partly Cloudy 0 to 5 mph WSW 7%
Sunday 57°F Mostly Sunny then Slight Chance Rain 5 to 10 mph W 18%
Sunday Night 35°F Mostly Clear 0 to 5 mph W 8%
Monday 60°F Sunny 5 to 10 mph WSW 3%
Monday Night 40°F Mostly Clear 5 mph W 2%

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

Growing snapshot for Crystal Lake, IL

Last spring frost
May 1
First fall frost
Oct 11
Growing season
162 days
Hardiness zone
5b

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

Climate data from the nearest NOAA station, Mc Henry -Wg Stratton L&D, Il (3.9 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 4, 2026.