Lake Forest, IL Weather & Growing Conditions
Tonight
60°F
Rain Showers
Rain showers. Cloudy, with a low around 60. South wind around 15 mph, with gusts as high as 25 mph. Chance of precipitation is 80%. New rainfall amounts less than a tenth of an inch possible.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Tonight | 60°F | Rain Showers | 15 mph S | 76% |
| Wednesday | 63°F | Rain Showers Likely | 15 mph SSW | 61% |
| Wednesday Night | 48°F | Slight Chance Rain Showers then Mostly Cloudy | 15 mph SW | 17% |
| Thursday | 56°F | Chance Rain Showers | 10 to 15 mph WSW | 34% |
| Thursday Night | 42°F | Rain Showers Likely | 10 to 15 mph WNW | 63% |
| Friday | 52°F | Chance Rain Showers | 15 mph N | 35% |
| Friday Night | 37°F | Mostly Cloudy | 5 to 10 mph NNW | 13% |
| Saturday | 52°F | Mostly Sunny | 5 mph WNW | 9% |
| Saturday Night | 36°F | Partly Cloudy | 0 to 5 mph WSW | 7% |
| Sunday | 56°F | Mostly Sunny then Slight Chance Rain | 5 to 10 mph W | 17% |
| Sunday Night | 37°F | Mostly Clear | 5 mph WNW | 9% |
| Monday | 58°F | Mostly Sunny | 5 to 10 mph W | 5% |
| Monday Night | 41°F | Mostly Clear | 5 to 10 mph W | 3% |
| Tuesday | 59°F | Mostly Sunny | 5 to 10 mph WNW | 1% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for Lake Forest, IL
Last spring frost
Apr 26
First fall frost
Oct 21
Growing season
176 days
Hardiness zone
6a
Explore more for Lake Forest, IL: full frost dates · planting calendar · Illinois frost dates
Climate data from the nearest NOAA station, Chicago Botanic Garden, Il (7.8 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 4, 2026.