National Weather Service Forecast for: Crystal Lake IL
Issued by: National Weather Service Chicago, IL
Updated: 10:36 am CST Feb 2, 2026
 
Today

Today: Scattered flurries before 4pm. Mostly cloudy, with a high near 26. West northwest wind 5 to 10 mph.
Scattered
Flurries
 Tonight

Tonight: A 20 percent chance of snow after midnight. Mostly cloudy, with a low around 13. West northwest wind around 5 mph, with gusts as high as 10 mph.
Mostly Cloudy
then Slight
Chance Snow
 Tuesday

Tuesday: Mostly sunny, with a high near 23. North wind 5 to 10 mph.
Mostly Sunny

 Tuesday
Night
Tuesday Night: Mostly clear, with a low around 7. Wind chill values as low as zero. North wind around 5 mph becoming calm after midnight.
Mostly Clear

 Wednesday

Wednesday: Sunny, with a high near 24. West northwest wind around 5 mph, with gusts as high as 10 mph.
Sunny

 Wednesday
Night
Wednesday Night: Partly cloudy, with a low around 11.
Partly Cloudy

 Thursday

Thursday: Partly sunny, with a high near 31.
Partly Sunny

 Thursday
Night
Thursday Night: A chance of snow before midnight. Mostly cloudy, with a low around 29.
Chance Snow
then Mostly
Cloudy
 Friday

Friday: Partly sunny, with a high near 32.
Partly Sunny
Hi 26 °F Lo 13 °F Hi 23 °F Lo 7 °F Hi 24 °F Lo 11 °F Hi 31 °F Lo 29 °F Hi 32 °F

 

Today
 
 Scattered flurries before 4pm. Mostly cloudy, with a high near 26. West northwest wind 5 to 10 mph.
Tonight
 
 A 20 percent chance of snow after midnight. Mostly cloudy, with a low around 13. West northwest wind around 5 mph, with gusts as high as 10 mph.
Tuesday
 
 Mostly sunny, with a high near 23. North wind 5 to 10 mph.
Tuesday Night
 
 Mostly clear, with a low around 7. Wind chill values as low as zero. North wind around 5 mph becoming calm after midnight.
Wednesday
 
 Sunny, with a high near 24. West northwest wind around 5 mph, with gusts as high as 10 mph.
Wednesday Night
 
 Partly cloudy, with a low around 11.
Thursday
 
 Partly sunny, with a high near 31.
Thursday Night
 
 A chance of snow before midnight. Mostly cloudy, with a low around 29.
Friday
 
 Partly sunny, with a high near 32.
Friday Night
 
 Partly cloudy, with a low around 10.
Saturday
 
 Mostly sunny, with a high near 22.
Saturday Night
 
 Mostly cloudy, with a low around 15.
Sunday
 
 Partly sunny, with a high near 28.

 

Forecast from NOAA-NWS for Crystal Lake IL.