All Countries
Flossmoor, IL
Full City Profile · Illinois · Will County County
3.8
/5.0
B+
Good
9,666
Population
2,634/sq mi density
$137,768
Median Income
$70,353 per capita
$309,100
Home Value
$319,546 Zillow
$2,191
Median Rent
21.4% income on rent
53°F
Avg Temperature
275 sunny days/yr
152
Violent Crime/100K
2,312 property/100K
B+
Overall
3.8 / 5.0
Good overall score based on economy, affordability, safety and education
A
Economy
4.3 / 5.0
$137,768 median income, 7.0% unemployment
A+
Affordability
5.0 / 5.0
$309,100 home value, $2,191/mo rent
F
Safety
1.0 / 5.0
152 violent crimes/100K
A+
Education
5.0 / 5.0
67.0% bachelor's degree or higher
Flossmoor experiences four distinct seasons with an average annual temperature of 53°F (12°C). Winters average 26°F in January while summers reach 77°F in July. The area gets 275 sunny days per year. Annual precipitation totals 40.9 inches. The area receives 38.8 inches of snow annually. Air quality is rated Good with a median AQI of 43.
Temperature
26°F Jan (-3°C)
77°F Jul (25°C)
| Annual Average | 52.5°F |
| 3% below US avg | |
| January Average | 26°F (-3°C) |
| July Average | 77°F (25°C) |
| Sunny Days | 275 days/yr |
Geography
| Elevation | 671 ft (205 m) |
| Area | 1.4 sq mi (3.7 km²) |
| Population Density | 2,634/sq mi |
| Coordinates | 41.5391°N, 87.6857°W |
| Timezone | America/Chicago |
| County | Will County County |
| Nearest Airport | Gary/Chicago International (GYY) 15 miles away |
Precipitation & Snow
Air Quality
| AQI Median | 43.0 |
| Rating | Good |
Air Pollutants (EPA 2023)
| Ozone (O₃) | 0.0479 ppm |
| PM2.5 (Fine Particles) | 9.5 μg/m³ |
Natural Hazard Risk
| Overall Risk | Relatively High |
| Risk Score | 97.3 / 100 |
| Social Vulnerability | 13.4 / 100 |
| Community Resilience | 92.4 / 100 |
Hazard Breakdown
| Tornado | Very High |
| Hurricane | Very Low |
| Earthquake | Relatively Moderate |
| Wildfire | Very Low |
| Flood | Relatively High |
| Hail | Relatively Low |
| Strong Wind | Relatively Low |
| Heat Wave | Relatively Moderate |
| Winter Weather | Relatively High |
| Lightning | Relatively High |
| Ice Storm | Relatively Moderate |
| Drought | Relatively Low |
| Cold Wave | Very High |
| Landslide | Very Low |
Source: FEMA National Risk Index v1.20 (Dec 2025)
Tsunami History
1 tsunami recorded within 500 km. Highest wave on record: 3.0 m (10 ft).
| Year | Location | Cause | Max Wave | Deaths | Distance |
| 1954 | MICHIGAN CITY, IN (LAKE MICHIGAN) | Avalanche | 3.0 m | 7 | 69 km |
Source: NOAA/NCEI Historical Tsunami Database. Sorted by wave height.
Monthly Weather
| Month | Avg Temperature | Precipitation | Summary |
|---|---|---|---|
| January | 26°F (-3°C) | 1.6 in | Coldest |
| February | 27°F (-3°C) | 1.5 in | Driest |
| March | 38°F (3°C) | 2.7 in | |
| April | 49°F (9°C) | 3.9 in | |
| May | 60°F (15°C) | 3.9 in | |
| June | 70°F (21°C) | 4.2 in | Wettest |
| July | 77°F (25°C) | 3.9 in | Warmest |
| August | 72°F (22°C) | 3.8 in | |
| September | 65°F (18°C) | 3.6 in | |
| October | 53°F (12°C) | 2.8 in | |
| November | 40°F (5°C) | 3.2 in | |
| December | 28°F (-2°C) | 2.6 in |
Flossmoor has a seasonal temperature swing of 51°F / from 26°F in January to 77°F in July. Total annual precipitation is 37.7 inches, with June being the wettest month (4.2") and February the driest (1.5").