National Weather Service Forecast for: Mount Prospect IL
Issued by: National Weather Service Chicago, IL
Updated: 3:01 am CDT Jun 22, 2026
 
Overnight

Overnight: A 30 percent chance of showers, mainly before 5am. Cloudy, with a low around 58. Northeast wind around 10 mph, with gusts as high as 20 mph.
Chance
Showers

 Monday

Monday: Mostly cloudy, then gradually becoming sunny, with a high near 70. North northeast wind around 10 mph, with gusts as high as 20 mph.
Decreasing
Clouds

 Monday
Night
Monday Night: Mostly clear, with a low around 54. North wind 5 to 10 mph, with gusts as high as 15 mph.
Mostly Clear

 Tuesday

Tuesday: Mostly sunny, with a high near 73. East northeast wind around 5 mph.
Mostly Sunny

 Tuesday
Night
Tuesday Night: Mostly cloudy, with a low around 58. East wind around 5 mph becoming south after midnight.
Mostly Cloudy

 Wednesday

Wednesday: A slight chance of showers, then showers likely and possibly a thunderstorm after 1pm. Partly sunny, with a high near 78. Chance of precipitation is 60%.
Slight Chance
Showers then
Showers
Likely
 Wednesday
Night
Wednesday Night: A 50 percent chance of showers and thunderstorms before 1am. Partly cloudy, with a low around 61.
Chance
T-storms then
Chance
Showers
 Thursday

Thursday: Mostly sunny, with a high near 78.
Mostly Sunny

 Thursday
Night
Thursday Night: Partly cloudy, with a low around 59.
Partly Cloudy
Lo 58 °F Hi 70 °F Lo 54 °F Hi 73 °F Lo 58 °F Hi 78 °F Lo 61 °F Hi 78 °F Lo 59 °F

Beach Hazards Statement
Hazardous Weather Outlook
 

Overnight
 
 A 30 percent chance of showers, mainly before 5am. Cloudy, with a low around 58. Northeast wind around 10 mph, with gusts as high as 20 mph.
Monday
 
 Mostly cloudy, then gradually becoming sunny, with a high near 70. North northeast wind around 10 mph, with gusts as high as 20 mph.
Monday Night
 
 Mostly clear, with a low around 54. North wind 5 to 10 mph, with gusts as high as 15 mph.
Tuesday
 
 Mostly sunny, with a high near 73. East northeast wind around 5 mph.
Tuesday Night
 
 Mostly cloudy, with a low around 58. East wind around 5 mph becoming south after midnight.
Wednesday
 
 A slight chance of showers, then showers likely and possibly a thunderstorm after 1pm. Partly sunny, with a high near 78. Chance of precipitation is 60%.
Wednesday Night
 
 A 50 percent chance of showers and thunderstorms before 1am. Partly cloudy, with a low around 61.
Thursday
 
 Mostly sunny, with a high near 78.
Thursday Night
 
 Partly cloudy, with a low around 59.
Friday
 
 Mostly sunny, with a high near 78.
Friday Night
 
 Mostly cloudy, with a low around 61.
Saturday
 
 Partly sunny, with a high near 80.
Saturday Night
 
 A chance of showers and thunderstorms. Mostly cloudy, with a low around 65.
Sunday
 
 Partly sunny, with a high near 88.

 

Forecast from NOAA-NWS for Mount Prospect IL.