Forest Lake, IL Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Forest Lake, a community in Lake County, Illinois.
Today
84°F
Mostly Sunny
Mostly sunny, with a high near 84. Southwest wind around 10 mph, with gusts as high as 20 mph.
7-day forecast for Forest Lake
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 84°F | Mostly Sunny | 10 mph SW | 0% |
| Tonight | 67°F | Mostly Cloudy then Chance Showers And Thunderstorms | 5 to 10 mph SW | 45% |
| Wednesday | 78°F | Showers And Thunderstorms Likely | 5 mph WSW | 74% |
| Wednesday Night | 62°F | Showers And Thunderstorms | 0 to 5 mph WNW | 83% |
| Thursday | 78°F | Rain Showers Likely then Slight Chance Showers And Thunderstorms | 0 to 5 mph NNE | 55% |
| Thursday Night | 60°F | Slight Chance Showers And Thunderstorms then Partly Cloudy | 0 to 5 mph S | 16% |
| Friday | 82°F | Mostly Sunny | 0 to 5 mph S | 3% |
| Friday Night | 63°F | Mostly Clear | 0 to 5 mph S | 7% |
| Saturday | 84°F | Mostly Sunny | 5 mph SW | 10% |
| Saturday Night | 68°F | Partly Cloudy then Slight Chance Showers And Thunderstorms | 5 mph SW | 21% |
| Sunday | 85°F | Slight Chance Showers And Thunderstorms | 5 to 10 mph SW | 21% |
| Sunday Night | 68°F | Chance Showers And Thunderstorms | 5 to 10 mph SW | 46% |
| Monday | 84°F | Chance Showers And Thunderstorms | 5 to 10 mph SSW | 46% |
| Monday Night | 68°F | Chance Showers And Thunderstorms | 5 mph W | 47% |
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 Aug 4, 2026.