Janesville, WI
Full City Profile · Wisconsin · Rock County County
3.3
/5.0
B
Good
65,813
Population
1,900/sq mi density
$71,664
Median Income
$36,639 per capita
$209,700
Home Value
$298,166 Zillow
$1,037
Median Rent
27.1% income on rent
48°F
Avg Temperature
143
Violent Crime/100K
1,855 property/100K
B
Overall
3.3 / 5.0
Good overall score based on economy, affordability, safety and education
A
Economy
4.0 / 5.0
$71,664 median income, 4.6% unemployment
A+
Affordability
5.0 / 5.0
$209,700 home value, $1,037/mo rent
F
Safety
1.0 / 5.0
143 violent crimes/100K
B
Education
3.2 / 5.0
26.9% bachelor's degree or higher
Janesville experiences four distinct seasons with an average annual temperature of 48°F (9°C). Winters average 20°F in January while summers reach 73°F in July. Annual precipitation totals 37.4 inches. The area receives 36.6 inches of snow annually. Air quality is rated Good with a median AQI of 41.
Temperature
20°F Jan (-7°C)
73°F Jul (23°C)
| Annual Average | 47.8°F |
| 11% below US avg | |
| January Average | 20°F (-7°C) |
| July Average | 73°F (23°C) |
Geography
| Elevation | 863 ft (263 m) |
| Area | 34.4 sq mi (89.0 km²) |
| Population Density | 1,900/sq mi |
| Coordinates | 42.6847°N, 89.0132°W |
| Timezone | America/Chicago |
| County | Rock County County |
| Nearest Airport | Southern Wisconsin Regional (JVL) 5 miles away |
Precipitation & Snow
Air Quality
| AQI Median | 41.0 |
| Rating | Good |
| Good Days % | 83.4% |
| Unhealthy Days | 2 |
Air Pollutants (EPA 2023)
| Ozone (O₃) | 0.0521 ppm |
Natural Hazard Risk
| Overall Risk | Relatively Moderate |
| Risk Score | 86.4 / 100 |
| Social Vulnerability | 18.5 / 100 |
| Community Resilience | 81.2 / 100 |
Hazard Breakdown
| Tornado | Relatively High |
| Hurricane | Very Low |
| Earthquake | Very Low |
| Wildfire | Very Low |
| Flood | Relatively Moderate |
| Hail | Relatively High |
| Strong Wind | Relatively High |
| Heat Wave | Relatively Moderate |
| Winter Weather | Relatively Moderate |
| Lightning | Relatively High |
| Ice Storm | Relatively Low |
| 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 | 20°F (-7°C) | 1.6 in | Coldest |
| February | 24°F (-5°C) | 1.6 in | Driest |
| March | 35°F (2°C) | 2.1 in | |
| April | 47°F (8°C) | 3.6 in | |
| May | 59°F (15°C) | 4.1 in | |
| June | 69°F (21°C) | 5.0 in | Wettest |
| July | 73°F (23°C) | 4.2 in | Warmest |
| August | 71°F (21°C) | 4.3 in | |
| September | 63°F (17°C) | 3.7 in | |
| October | 51°F (10°C) | 3.0 in | |
| November | 37°F (3°C) | 2.3 in | |
| December | 26°F (-3°C) | 1.9 in |
Janesville has a seasonal temperature swing of 53°F / from 20°F in January to 73°F in July. Total annual precipitation is 37.4 inches, with June being the wettest month (5.0") and February the driest (1.6").