Mount Prospect, IL Weather & Growing Conditions
Tonight
62°F
Isolated Rain Showers then Showers And Thunderstorms Likely
Isolated rain showers before 8pm, then showers and thunderstorms likely. Mostly cloudy, with a low around 62. East wind 10 to 15 mph. Chance of precipitation is 60%. New rainfall amounts between a quarter and half of an inch possible.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Tonight | 62°F | Isolated Rain Showers then Showers And Thunderstorms Likely | 10 to 15 mph E | 55% |
| Saturday | 76°F | Showers And Thunderstorms Likely | 10 to 15 mph SE | 89% |
| Saturday Night | 64°F | Showers And Thunderstorms Likely then Showers And Thunderstorms | 5 to 10 mph NNE | 81% |
| Sunday | 68°F | Showers And Thunderstorms | 10 to 15 mph NNE | 79% |
| Sunday Night | 56°F | Chance Rain Showers | 15 mph NE | 53% |
| Monday | 65°F | Chance Rain Showers | 15 mph ENE | 45% |
| Monday Night | 53°F | Chance Rain Showers | 10 to 15 mph ENE | 32% |
| Tuesday | 63°F | Slight Chance Rain Showers | 10 to 15 mph NE | 22% |
| Tuesday Night | 53°F | Slight Chance Rain Showers then Mostly Cloudy | 5 to 10 mph NE | 19% |
| Wednesday | 65°F | Partly Sunny | 5 to 10 mph NE | 11% |
| Wednesday Night | 54°F | Mostly Cloudy | 5 to 10 mph NNE | 3% |
| Thursday | 68°F | Partly Sunny | 5 to 10 mph NNE | 6% |
| Thursday Night | 55°F | Mostly Cloudy | 5 mph NNE | 4% |
| Friday | 70°F | Mostly Sunny | 5 mph NNE | 5% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for Mount Prospect, IL
Last spring frost
Apr 19
First fall frost
Oct 26
Growing season
190 days
Hardiness zone
6a
Explore more for Mount Prospect, IL: full frost dates · planting calendar · Illinois frost dates
Climate data from the nearest NOAA station, Chicago Palwaukee Ap, Il (4.1 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.