Millbrook, IL
Full City Profile · Illinois · Kendall County County
4.7
/5.0
A+
Excellent
298
Population
161/sq mi density
$128,750
Median Income
$41,266 per capita
$350,000
Home Value
$300,599 Zillow
$1,100
Median Rent
15.0% income on rent
49°F
Avg Temperature
A+
Overall
4.7 / 5.0
Strong
A+
Economy
4.8 / 5.0
$128,750 median income, 2.6% unemployment
A+
Affordability
5.0 / 5.0
$350,000 home value, $1,100/mo rent
A
Education
4.4 / 5.0
42.1% bachelor's degree or higher
Millbrook experiences four distinct seasons with an average annual temperature of 49°F (9°C). Winters average 23°F in January while summers reach 73°F in July. Annual precipitation totals 40.0 inches. The area receives 27.9 inches of snow annually.
Temperature
23°F Jan (-5°C)
73°F Jul (23°C)
| Annual Average | 49.4°F |
| 9% below US avg | |
| January Average | 23°F (-5°C) |
| July Average | 73°F (23°C) |
Geography
| Elevation | 625 ft (191 m) |
| Area | 0.8 sq mi (2.1 km²) |
| Population Density | 161/sq mi |
| Coordinates | 41.6071°N, 88.5454°W |
| Timezone | America/Chicago |
| County | Kendall County County |
| Nearest Airport | Joliet Regional (JOT) 20 miles away |
Precipitation & Snow
Air Quality
Natural Hazard Risk
| Overall Risk | Relatively Low |
| Risk Score | 80.3 / 100 |
| Social Vulnerability | 10.6 / 100 |
| Community Resilience | 96.0 / 100 |
Hazard Breakdown
| Tornado | Relatively Moderate |
| Hurricane | Very Low |
| Earthquake | Relatively Low |
| Wildfire | Very Low |
| Flood | Relatively Moderate |
| Hail | Very Low |
| Strong Wind | Relatively High |
| Heat Wave | Relatively Low |
| Winter Weather | Relatively Low |
| Lightning | Relatively Low |
| Ice Storm | Relatively Low |
| Drought | Relatively Low |
| Cold Wave | Relatively 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 | 139 km |
Source: NOAA/NCEI Historical Tsunami Database. Sorted by wave height.
Monthly Weather
| Month | Avg Temperature | Precipitation | Summary |
|---|---|---|---|
| January | 23°F (-5°C) | 2.0 in | Coldest |
| February | 27°F (-3°C) | 2.0 in | Driest |
| March | 38°F (3°C) | 2.6 in | |
| April | 49°F (9°C) | 4.0 in | |
| May | 60°F (16°C) | 4.5 in | |
| June | 70°F (21°C) | 5.0 in | Wettest |
| July | 73°F (23°C) | 4.3 in | Warmest |
| August | 71°F (22°C) | 3.9 in | |
| September | 64°F (18°C) | 3.6 in | |
| October | 52°F (11°C) | 3.5 in | |
| November | 39°F (4°C) | 2.6 in | |
| December | 28°F (-2°C) | 2.1 in |
Millbrook has a seasonal temperature swing of 51°F / from 23°F in January to 73°F in July. Total annual precipitation is 40.0 inches, with June being the wettest month (5.0") and February the driest (2.0").