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Weather & Climate in Dellwood, WI
Temperature, precipitation, air quality, natural hazards, and monthly weather data.
Dellwood has a cool climate with an average annual temperature of 45°F (7°C). Winters average 16°F in January while summers reach 71°F in July. The area gets 260 sunny days per year, above the national average. Annual precipitation totals 35.1 inches. The area receives 52.0 inches of snow annually, making winter weather a significant factor for residents. Air quality is rated Good with a median AQI of 38. The city sits at an elevation of 909 feet.
Temperature
16°F Jan (-9°C)
71°F Jul (22°C)
| Annual Average | 45.0°F |
| 17% below US avg | |
| January Average | 16°F (-9°C) |
| July Average | 71°F (22°C) |
| Sunny Days | 260 days/yr |
Geography
| Elevation | 909 ft (277 m) |
| Area | 5.3 sq mi (13.8 km²) |
| Population Density | 110/sq mi |
| Coordinates | 43.9451°N, 89.9280°W |
| Timezone | America/Chicago |
| County | Adams County County |
| Nearest Airport | Tri-County Regional (LNR) 52 miles away |
Precipitation & Snow
Air Quality
| AQI Median | 38.0 |
| Rating | Good |
Natural Hazard Risk
| Overall Risk | Relatively Low |
| Risk Score | 70.9 / 100 |
| Social Vulnerability | 86.5 / 100 |
| Community Resilience | 21.9 / 100 |
Hazard Breakdown
| Tornado | Relatively Moderate |
| Hurricane | Very Low |
| Earthquake | Very Low |
| Wildfire | Very Low |
| Flood | Relatively Low |
| Hail | Relatively Moderate |
| Strong Wind | Relatively Moderate |
| 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)
Tornado History
383 tornadoes (EF0+) recorded within 100 km since 1950. Strongest on record: EF4. Total: 26 fatalities, 410 injuries.
| Date | Rating | Distance | Path | Fatalities |
| Apr 27, 1984 | EF4 | 95 km | 27.5 mi | 1 |
| Aug 31, 1977 | EF4 | 94 km | 31.8 mi | 0 |
| Apr 21, 1974 | EF4 | 91 km | 26.0 mi | 0 |
| Apr 19, 1957 | EF4 | 22 km | 21.1 mi | 1 |
| Apr 3, 1956 | EF4 | 77 km | 11.5 mi | 7 |
| Sep 26, 1951 | EF4 | 76 km | 9.0 mi | 1 |
| Sep 26, 1951 | EF4 | 66 km | 26.4 mi | 6 |
| Jun 23, 2004 | EF3 | 84 km | 7.6 mi | 1 |
| Jun 23, 2004 | EF3 | 76 km | 33.3 mi | 0 |
| Aug 27, 1994 | EF3 | 17 km | 10.5 mi | 2 |
| Aug 29, 1992 | EF3 | 36 km | 28.0 mi | 1 |
| Jun 8, 1984 | EF3 | 79 km | 29.0 mi | 0 |
| Jul 3, 1983 | EF3 | 28 km | 1.0 mi | 0 |
| Apr 7, 1980 | EF3 | 93 km | 1.2 mi | 0 |
| Jun 5, 1977 | EF3 | 97 km | 69.5 mi | 0 |
| Jun 4, 1975 | EF3 | 97 km | 2.3 mi | 0 |
| Aug 2, 1967 | EF3 | 99 km | 0.1 mi | 2 |
| Aug 16, 1963 | EF3 | 74 km | 9.6 mi | 0 |
| Aug 16, 1963 | EF3 | 74 km | 9.6 mi | 0 |
| Aug 16, 1963 | EF3 | 74 km | 9.6 mi | 0 |
Source: NOAA Storm Prediction Center (EF0+, 1950–2024, US only).
Wildfire History
20 wildfires (100+ acres) recorded within 100 km. Largest: COTTONVILLE INCIDENT (3,466 acres, 2005).
| Year | Name | Acres Burned | Distance |
| 2005 | COTTONVILLE INCIDENT | 3,466 | 23 km |
| 1987 | BIG BURN | 3,154 | 32 km |
| 2024 | 2024 DOD HARDWOOD RANGE RX | 2,717 | 34 km |
| 1994 | BIG BURN | 2,248 | 30 km |
| 2023 | 2023 RX | 1,992 | 35 km |
| 1997 | BIG BURN | 1,642 | 32 km |
| 2004 | POOL ONE NORTH | 1,576 | 23 km |
| 1998 | UNNAMED | 1,297 | 31 km |
| 2021 | 2021 DOD HARDWOOD RANGE RX | 987 | 35 km |
| 2007 | UNNAMED | 981 | 26 km |
| 2003 | UNNAMED | 901 | 32 km |
| 1998 | PR 17 | 896 | 23 km |
| 2007 | UNNAMED | 875 | 22 km |
| 2009 | UNNAMED | 867 | 26 km |
| 2007 | PR 16 | 778 | 31 km |
| 2006 | PR 17 RX FIRE | 701 | 31 km |
| 2018 | 2018 BADGER RX BURNS | 659 | 65 km |
| 2005 | UNNAMED | 657 | 27 km |
| 2003 | PR 17 | 632 | 31 km |
| 2019 | 2019 BADGER RX BURNS | 627 | 66 km |
Source: NIFC/IRWIN Wildfire Records (100+ acres).
Monthly Weather
| Month | Avg Temperature | Precipitation | Summary |
|---|---|---|---|
| January | 16°F (-9°C) | 0.9 in | Coldest, Driest |
| February | 20°F (-7°C) | 1.0 in | |
| March | 31°F (-0°C) | 2.1 in | |
| April | 45°F (7°C) | 3.0 in | |
| May | 57°F (14°C) | 3.5 in | |
| June | 66°F (19°C) | 3.7 in | |
| July | 71°F (22°C) | 3.8 in | Warmest |
| August | 68°F (20°C) | 4.1 in | |
| September | 60°F (16°C) | 4.1 in | Wettest |
| October | 49°F (9°C) | 2.4 in | |
| November | 34°F (1°C) | 2.1 in | |
| December | 21°F (-6°C) | 1.3 in |
Dellwood has a seasonal temperature swing of 55°F / from 16°F in January to 71°F in July. Total annual precipitation is 32.0 inches, with September being the wettest month (4.1") and January the driest (0.9").