Prospect Heights, IL Weather & Growing Conditions
Overnight
61°F
Rain Showers
Rain showers. Cloudy. Low around 61, with temperatures rising to around 64 overnight. South wind around 15 mph, with gusts as high as 25 mph. Chance of precipitation is 80%. New rainfall amounts between a tenth and quarter of an inch possible.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Overnight | 61°F | Rain Showers | 15 mph S | 80% |
| Wednesday | 64°F | Chance Rain Showers | 15 mph SSW | 39% |
| Wednesday Night | 47°F | Mostly Cloudy | 15 mph SW | 12% |
| Thursday | 56°F | Chance Rain Showers | 10 to 15 mph WSW | 45% |
| Thursday Night | 40°F | Rain Showers Likely | 10 to 15 mph NW | 61% |
| Friday | 50°F | Slight Chance Rain Showers then Mostly Cloudy | 15 mph NNW | 16% |
| Friday Night | 36°F | Partly Cloudy | 5 to 10 mph NNW | 3% |
| Saturday | 51°F | Mostly Sunny | 5 mph NW | 1% |
| Saturday Night | 35°F | Partly Cloudy | 5 mph W | 0% |
| Sunday | 56°F | Sunny | 5 to 10 mph W | 6% |
| Sunday Night | 36°F | Mostly Clear | 5 mph W | 1% |
| Monday | 60°F | Mostly Sunny | 5 to 10 mph WSW | 0% |
| Monday Night | 41°F | Partly Cloudy | 5 to 10 mph WSW | 1% |
| Tuesday | 61°F | Sunny | 5 mph WNW | 0% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for Prospect Heights, IL
Last spring frost
Apr 19
First fall frost
Oct 26
Growing season
190 days
Hardiness zone
6a
Explore more for Prospect Heights, IL: full frost dates · planting calendar · Illinois frost dates
Climate data from the nearest NOAA station, Chicago Palwaukee Ap, Il (1.7 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 4, 2026.