Lake Summerset, Illinois Weather
Day 93 of summer. Read today’s microseason across nine climate regions →
Lake Summerset weather forecast — hour by hour, 7-day outlook, NOAA radar
Conditions updated 1:30 AM CDT · Open-Meteo
- TodaySep 21Overcast19%—64°54°—
- TuesdaySep 22Overcast14%—61°49°-3°
- WednesdaySep 23Overcast——67°47°+6°
- ThursdaySep 24Overcast——66°51°-1°
- FridaySep 25Overcast——67°54°+1°
- SaturdaySep 26Light Drizzle—0.06″57°54°-10°
- SundaySep 27Overcast12%—65°54°+8°
Air quality now AQI 31 · Good
AQI 31 (Good), driven by Ozone. AQI flat over the last 6 hours (within ±3 points).
OK No precautions needed for the general population; unusually sensitive individuals may consider limiting prolonged outdoor exertion.
Trends
Seven days of AQI and PM2.5.
Hourly air-quality data from the Copernicus Atmosphere Monitoring Service, charted across the past and next several days. Dashed lines mark the AQI breakpoints at 50 (Good → Moderate) and 100 (Moderate → Unhealthy for Sensitive Groups).
September dries up ditches or breaks down bridges.
- Moonrise
- 4:38 PM
- Moonset
- 1:10 AM
- In sign
- ♑︎ Capricorn
Lake Summerset at a glance
- Today vs. normal: Today averages 59°F (high 64°F, low 54°F), about the 60°F normal for Sep 21
- Last frost: April 29 (1991–2020 median, NOAA station 19 km away)
- Microseason: Sep 21–25
- Planting calendar: September — plant garlic (overwinter); harvest tomatoes, peppers, beans, summer squash, winter squash
15-Day Forecast — Lake Summerset
- Mon63°54°19%
- Tue61°49°14%
- Wed67°47°0%
- Thu66°51°1%
- Fri67°54°1%
- Sat57°54°7%
- Sun65°54°12%
- Mon71°48°18%
- Tue69°54°31%
- Wed67°48°22%
- Thu68°47°25%
- Fri63°56°29%
- Sat60°56°20%
- Sun79°57°23%
- Mon65°50°21%
Forecast data from Open-Meteo (CC BY 4.0).
Right now in the garden
Fall planting + final harvests
As of September 21, the season's first frost (typically October 12) is approaching. Pick what frost-tender plants still carry before the next cold front. This city's planting calendar for September: plant garlic (overwinter); harvest tomatoes, peppers, beans, summer squash, and winter squash.
Sun & seasons in Lake Summerset
Lake Summerset sits in Winnebago County, where the year’s longest day runs 15h 18m of daylight and its shortest just 9h 4m — a swing of +6h 14m between the June and December solstices. Clocks spring forward on Sunday, March 8, 2026 and fall back on Sunday, November 1, 2026.
Chicago, the state’s largest city, lies about 97 miles to the ESE. The nearest town Lake Summerset tracks is Rockford, roughly 22 miles to the SE.
Air quality in Lake Summerset
Air quality in Lake Summerset’s county has held roughly steady since 2020; its cleanest year on record was 2025 (median AQI 40).
Planting calendar
| Month | Plant | Harvest |
|---|---|---|
| April | lettuce, peas, spinach, radishes | — |
| May | lettuce, peas, spinach, radishes, tomatoes, peppers, beans, squash | lettuce, spinach, radishes |
| June | tomatoes, peppers, beans, squash | lettuce, peas, spinach, radishes |
| July | tomatoes, peppers, beans, squash, fall brassicas, carrots | lettuce, peas, spinach, beans, summer squash, garlic |
| August | — | tomatoes, peppers, beans, summer squash, garlic |
| September | garlic (overwinter) | tomatoes, peppers, beans, summer squash, winter squash |
| October | — | tomatoes, peppers, beans, summer squash, winter squash, fall brassicas, carrots |
| November | — | fall brassicas, carrots |
A year in weather
Lake Summerset peaks at about 72°F in July and bottoms near 19°F in January; June brings the heaviest rain (5.6 inches) and January the least (1.6 inches).
| Month | Mean temp | Precip | Rainy days |
|---|---|---|---|
| January | 19° | 1.6″ | 10 |
| February | 23° | 1.8″ | 8 |
| March | 35° | 2.1″ | 10 |
| April | 47° | 3.7″ | 12 |
| May | 59° | 4.2″ | 13 |
| June | 69° | 5.6″ | 12 |
| July | 72° | 4.0″ | 10 |
| August | 70° | 4.3″ | 10 |
| September | 62° | 3.8″ | 9 |
| October | 50° | 2.9″ | 10 |
| November | 37° | 2.4″ | 9 |
| December | 25° | 2.0″ | 10 |
Regional context
Similar climates Davis, IL, Durand, IL, Rock City, IL
Per NOAA NCEI 1991-2020 normals, Lake Summerset runs from a 19°F January mean to 72°F in July, a 53°F seasonal spread, with near 38.3 inches of precipitation across about 122 wet days.
Precipitation in Lake Summerset runs summer-dominant: June averages 5.6 inches across 12.2 days of warm-season storms, while January drops to 1.6 inches over 9.6 rainy days of drier cool air. Lake Summerset shares that warm-season-wet pattern with places like Davis, IL, Durand, IL and Rock City, IL.
Once Lake Summerset passes April 29, freezes fade and Lake Summerset's beds take kale, peas, spinach, and parsnips. Heat-demanding starts go out a fortnight on in Lake Summerset, after the soil warms and cold snaps clear. By October 12, frost is back in Lake Summerset — protect or harvest anything tender. That date is a median: Lake Summerset freezes sooner in half of years.
Similar climates: Davis, IL, Durand, IL, Rock City, IL, Dakota, IL, Pecatonica, IL.
Frequently asked
- When does it freeze in Lake Summerset?
- Lake Summerset's last spring frost lands near April 29, and in Lake Summerset the first fall frost follows around October 12.
- What is the rainy season in Lake Summerset?
- Lake Summerset sees its heaviest rain in June (around 5.6 inches), part of roughly 38 inches a year.
- What is the warmest month in Lake Summerset?
- Lake Summerset peaks in July, when the mean runs near 72°F.
- What is the coldest month in Lake Summerset?
- January is Lake Summerset's coldest month, averaging about 19°F.
- When can I start a vegetable garden in Lake Summerset?
- In Lake Summerset, sow peas and hardy greens around April 29; Lake Summerset's tomatoes and peppers wait two weeks more.
- How many rainy days does Lake Summerset get?
- Expect roughly 122 wet days a year in Lake Summerset.
- What hardiness zone is Lake Summerset?
- Since January in Lake Summerset averages 19°F, Lake Summerset's USDA zone follows that floor — confirm it by ZIP.
- What is the 10-day forecast for Lake Summerset?
- Lake Summerset's extended outlook — daily high and low temperatures and precipitation chances for each upcoming day — is in the daily forecast above.
- Will it rain this week in Lake Summerset?
- See this week's day-by-day rain chances for Lake Summerset in the daily forecast above, and the next 24 hours in the hourly chart.
- What is the weather like right now in Lake Summerset?
- Current conditions for Lake Summerset and the next 24 hours — temperature, precipitation chance, and wind by the hour — are in the hourly forecast chart above.
- How often is the Lake Summerset forecast updated?
- The Lake Summerset forecast on this page is built from Open-Meteo weather-model data and refreshes regularly through the day.
- When are sunrise and sunset in Lake Summerset?
- Today's sunrise and sunset times for Lake Summerset are in the Almanac section above, along with civil dawn, civil dusk, and day length. Day length is longest near the summer solstice and shortest near the winter solstice.
- How accurate is the weather forecast for Lake Summerset?
- The next few days in Lake Summerset's forecast are the most reliable; accuracy declines beyond about a week as weather-model uncertainty grows.
Lake Summerset sits at 42.5°N; its climate zone is warm-summer humid continental (Köppen approximation).
ZIP codes in Lake Summerset
- 61019