Lake Summerset, IL
Full City Profile · Illinois · Winnebago County County
4.1
/5.0
A
Great
2,240
Population
1,057/sq mi density
$105,588
Median Income
$43,625 per capita
$226,700
Home Value
$259,436 Zillow
$1,206
Median Rent
36.9% income on rent
47°F
Avg Temperature
A
Overall
4.1 / 5.0
Strong
B+
Economy
3.9 / 5.0
$105,588 median income, 9.6% unemployment
A+
Affordability
5.0 / 5.0
$226,700 home value, $1,206/mo rent
B
Education
3.4 / 5.0
29.5% bachelor's degree or higher
Lake Summerset experiences four distinct seasons with an average annual temperature of 47°F (8°C). Winters average 19°F in January while summers reach 72°F in July. Annual precipitation totals 38.9 inches. The area receives 37.3 inches of snow annually. Air quality is rated Good with a median AQI of 43.
Temperature
19°F Jan (-7°C)
72°F Jul (22°C)
| Annual Average | 47.2°F |
| 13% below US avg | |
| January Average | 19°F (-7°C) |
| July Average | 72°F (22°C) |
Geography
| Elevation | 853 ft (260 m) |
| Area | 2.1 sq mi (5.5 km²) |
| Population Density | 1,057/sq mi |
| Coordinates | 42.4540°N, 89.3901°W |
| Timezone | America/Chicago |
| County | Winnebago County County |
| Nearest Airport | Southern Wisconsin Regional (JVL) 21 miles away |
Precipitation & Snow
Air Quality
| AQI Median | 43.0 |
| Rating | Good |
| Good Days % | 69.0% |
| Unhealthy Days | 3 |
Air Pollutants (EPA 2023)
| Ozone (O₃) | 0.0475 ppm |
| PM2.5 (Fine Particles) | 10.2 μg/m³ |
Natural Hazard Risk
| Overall Risk | Relatively Moderate |
| Risk Score | 92.4 / 100 |
| Social Vulnerability | 38.9 / 100 |
| Community Resilience | 68.5 / 100 |
Hazard Breakdown
| Tornado | Relatively High |
| Hurricane | Very Low |
| Earthquake | Relatively Low |
| Wildfire | Very Low |
| Flood | Relatively High |
| Hail | Relatively High |
| Strong Wind | Relatively High |
| Heat Wave | Relatively Moderate |
| Winter Weather | Relatively Moderate |
| Lightning | Relatively High |
| Ice Storm | Relatively High |
| Drought | Relatively Low |
| Cold Wave | Relatively High |
| Landslide | Very Low |
Source: FEMA National Risk Index v1.20 (Dec 2025)
Monthly Weather
| Month | Avg Temperature | Precipitation | Summary |
|---|---|---|---|
| January | 19°F (-7°C) | 1.6 in | Coldest |
| February | 23°F (-5°C) | 1.6 in | Driest |
| March | 35°F (1°C) | 2.1 in | |
| April | 47°F (8°C) | 3.7 in | |
| May | 59°F (15°C) | 4.2 in | |
| June | 69°F (20°C) | 5.6 in | Wettest |
| July | 72°F (22°C) | 4.0 in | Warmest |
| August | 70°F (21°C) | 4.2 in | |
| September | 62°F (17°C) | 3.9 in | |
| October | 50°F (10°C) | 2.9 in | |
| November | 37°F (3°C) | 2.6 in | |
| December | 25°F (-4°C) | 2.3 in |
Lake Summerset has a seasonal temperature swing of 53°F / from 19°F in January to 72°F in July. Total annual precipitation is 38.9 inches, with June being the wettest month (5.6") and February the driest (1.6").