Forest Lake, IL Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Forest Lake, a community in Lake County, Illinois.
This Afternoon
71°F
Slight Chance Rain Showers
A slight chance of rain showers. Mostly cloudy. High near 71, with temperatures falling to around 69 in the afternoon. East wind around 10 mph, with gusts as high as 20 mph. Chance of precipitation is 20%.
7-day forecast for Forest Lake
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| This Afternoon | 71°F | Slight Chance Rain Showers | 10 mph E | 22% |
| Tonight | 61°F | Slight Chance Rain Showers then Showers And Thunderstorms Likely | 10 to 15 mph E | 64% |
| Saturday | 75°F | Showers And Thunderstorms then Showers And Thunderstorms Likely | 10 to 15 mph SE | 94% |
| Saturday Night | 62°F | Showers And Thunderstorms Likely then Showers And Thunderstorms | 5 to 10 mph ENE | 80% |
| Sunday | 67°F | Showers And Thunderstorms | 10 to 15 mph NE | 75% |
| Sunday Night | 55°F | Chance Rain Showers | 15 mph NE | 47% |
| Monday | 63°F | Chance Rain Showers | 15 mph ENE | 42% |
| Monday Night | 51°F | Chance Rain Showers | 10 to 15 mph ENE | 36% |
| Tuesday | 62°F | Slight Chance Rain Showers | 10 to 15 mph NE | 21% |
| Tuesday Night | 51°F | Slight Chance Rain Showers then Mostly Cloudy | 5 to 10 mph NE | 17% |
| Wednesday | 64°F | Partly Sunny | 5 to 10 mph NE | 11% |
| Wednesday Night | 51°F | Mostly Cloudy | 5 mph NNE | 4% |
| Thursday | 67°F | Partly Sunny | 5 mph NNE | 6% |
| Thursday Night | 52°F | Mostly Cloudy | 0 to 5 mph NNE | 4% |
Forecast source: National Weather Service (api.weather.gov) for Forest Lake (42.212, -88.052). Updated through the day.
Growing snapshot for Forest Lake
Last spring frost
Apr 29
First fall frost
Oct 20
Growing season
172 days
Hardiness zone
5b
More local growing data for Forest Lake: nearby ZIP 60047 weather · frost dates · planting calendar · Illinois frost dates
Nearby towns & communities
Antioch
Bannockburn
Beach Park
Buffalo Grove
Burtons Bridge
Deer Park
Deerfield
Fox Lake
Fox Lake Hills
Gages Lake
Grandwood Park
Grayslake
Green Oaks
Gurnee
Hainesville
Hawthorn Woods
Highland Park
Highwood
Holiday Hills
Indian Creek
Island Lake
Kildeer
Knollwood
Lake Bluff
Lake Forest
Lake Villa
Lake Zurich
Libertyville
Lincolnshire
Lindenhurst
Climate data from the nearest NOAA station, Mundelein 4 Wsw, Il (4 mi from Forest Lake). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.