Lannon, WI
Full City Profile · Wisconsin · Waukesha County County
4.6
/5.0
A+
Excellent
1,475
Population
597/sq mi density
$79,191
Median Income
$56,946 per capita
$255,900
Home Value
$519,926 Zillow
47°F
Avg Temperature
A+
Overall
4.6 / 5.0
Strong
A+
Economy
4.6 / 5.0
$79,191 median income, 1.5% unemployment
A+
Affordability
4.9 / 5.0
$255,900 home value, /mo rent
A
Education
4.5 / 5.0
43.4% bachelor's degree or higher
Lannon 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 36.8 inches. The area receives 54.3 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 | 46.5°F |
| 14% below US avg | |
| January Average | 19°F (-7°C) |
| July Average | 72°F (22°C) |
Geography
| Elevation | 889 ft (271 m) |
| Area | 2.5 sq mi (6.4 km²) |
| Population Density | 597/sq mi |
| Coordinates | 43.1572°N, 88.1582°W |
| Timezone | America/Chicago |
| County | Waukesha County County |
| Nearest Airport | General Mitchell International (MKE) 20 miles away |
Precipitation & Snow
Air Quality
| AQI Median | 43.0 |
| Rating | Good |
| Good Days % | 71.0% |
| Unhealthy Days | 1 |
Air Pollutants (EPA 2023)
| Ozone (O₃) | 0.0501 ppm |
| PM2.5 (Fine Particles) | 10.4 μg/m³ |
Natural Hazard Risk
| Overall Risk | Relatively Moderate |
| Risk Score | 88.9 / 100 |
| Social Vulnerability | 10.6 / 100 |
| Community Resilience | 97.4 / 100 |
Hazard Breakdown
| Tornado | Relatively High |
| Hurricane | Very Low |
| Earthquake | Very Low |
| Wildfire | Very Low |
| Flood | Relatively Moderate |
| Hail | Relatively High |
| Strong Wind | Relatively Moderate |
| Heat Wave | Relatively Moderate |
| Winter Weather | Relatively High |
| Lightning | Relatively Moderate |
| Ice Storm | Relatively Moderate |
| Drought | Relatively Low |
| Cold Wave | Relatively High |
| Landslide | Relatively Low |
Source: FEMA National Risk Index v1.20 (Dec 2025)
Monthly Weather
| Month | Avg Temperature | Precipitation | Summary |
|---|---|---|---|
| January | 19°F (-7°C) | 1.7 in | Coldest, Driest |
| February | 23°F (-5°C) | 1.9 in | |
| March | 33°F (1°C) | 2.1 in | |
| April | 45°F (7°C) | 3.9 in | |
| May | 57°F (14°C) | 4.1 in | |
| June | 67°F (19°C) | 4.7 in | Wettest |
| July | 72°F (22°C) | 4.2 in | Warmest |
| August | 70°F (21°C) | 3.7 in | |
| September | 62°F (17°C) | 3.3 in | |
| October | 50°F (10°C) | 2.9 in | |
| November | 36°F (2°C) | 2.3 in | |
| December | 25°F (-4°C) | 2.1 in |
Lannon has a seasonal temperature swing of 53°F / from 19°F in January to 72°F in July. Total annual precipitation is 36.8 inches, with June being the wettest month (4.7") and January the driest (1.7").