Lake Summerset, IL Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Lake Summerset, a community in Stephenson County, Illinois.
Tonight
56°F
Rain
Rain. Cloudy. Low around 56, with temperatures rising to around 59 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 for Lake Summerset
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Tonight | 56°F | Rain | 15 mph S | 82% |
| Wednesday | 58°F | Chance Rain then Chance Rain Showers | 15 mph SSW | 47% |
| Wednesday Night | 45°F | Chance Rain Showers | 15 mph SW | 32% |
| Thursday | 53°F | Rain Showers Likely | 10 to 15 mph WSW | 64% |
| Thursday Night | 39°F | Chance Rain Showers | 10 to 15 mph NNW | 30% |
| Friday | 49°F | Partly Sunny | 10 to 15 mph N | 14% |
| Friday Night | 32°F | Partly Cloudy | 0 to 10 mph NNW | 1% |
| Saturday | 52°F | Mostly Sunny | 0 to 5 mph WNW | 2% |
| Saturday Night | 33°F | Partly Cloudy | 5 mph WSW | 4% |
| Sunday | 57°F | Mostly Sunny then Slight Chance Rain | 5 to 10 mph W | 15% |
| Sunday Night | 34°F | Mostly Clear | 5 to 10 mph W | 4% |
| Monday | 59°F | Sunny | 5 to 15 mph SW | 1% |
| Monday Night | 38°F | Mostly Clear | 5 to 10 mph W | 0% |
| Tuesday | 60°F | Sunny | 5 to 10 mph WNW | 1% |
Forecast source: National Weather Service (api.weather.gov) for Lake Summerset (42.454, -89.390). Updated through the day.
Growing snapshot for Lake Summerset
Last spring frost
Apr 29
First fall frost
Oct 12
Growing season
165 days
Hardiness zone
5a
More local growing data for Lake Summerset: nearby ZIP 61019 weather · frost dates · planting calendar · Illinois frost dates
Nearby towns & communities
Adeline
Cedarville
Dakota
Davis
Freeport
German Valley
Lena
Orangeville
Pearl City
Ridott
Rock City
Willow Lake
Winslow
Climate data from the nearest NOAA station, Brodhead Wwtp, Wi (12.4 mi from Lake Summerset). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 4, 2026.