All Countries
Weather & Climate in Marshalltown, IA
Temperature, precipitation, air quality, natural hazards, and monthly weather data.
Marshalltown experiences four distinct seasons with an average annual temperature of 48°F (9°C). Winters average 18°F in January while summers reach 73°F in July. The area gets 260 sunny days per year, above the national average. Annual precipitation totals 37.9 inches. The area receives 25.3 inches of snow annually, a moderate snowfall amount. Air quality is rated Good with a median AQI of 43. The city sits at an elevation of 897 feet.
Temperature
18°F Jan (-8°C)
73°F Jul (23°C)
| Annual Average | 47.6°F |
| 12% below US avg | |
| January Average | 18°F (-8°C) |
| July Average | 73°F (23°C) |
| Sunny Days | 260 days/yr |
Geography
| Elevation | 897 ft (273 m) |
| Area | 19.3 sq mi (50.0 km²) |
| Population Density | 1,432/sq mi |
| Coordinates | 42.0343°N, 92.9063°W |
| Timezone | America/Chicago |
| County | Marshall County County |
| Nearest Airport | Waterloo Regional (ALO) 44 miles away |
Precipitation & Snow
Air Quality
| AQI Median | 43.0 |
| Rating | Good |
Natural Hazard Risk
| Overall Risk | Relatively Low |
| Risk Score | 62.5 / 100 |
| Social Vulnerability | 39.9 / 100 |
| Community Resilience | 63.4 / 100 |
Hazard Breakdown
| Tornado | Relatively Moderate |
| Hurricane | Very Low |
| Earthquake | Very Low |
| Wildfire | Very Low |
| Flood | Relatively Low |
| Hail | Relatively Moderate |
| Strong Wind | Relatively High |
| Heat Wave | Very Low |
| Winter Weather | Relatively Moderate |
| Lightning | Relatively Low |
| Ice Storm | Relatively Low |
| Drought | Relatively High |
| Cold Wave | Relatively Low |
| Landslide | Very Low |
Source: FEMA National Risk Index v1.20 (Dec 2025)
Tornado History
728 tornadoes (EF0+) recorded within 100 km since 1950. Strongest on record: EF5. Total: 36 fatalities, 1,016 injuries.
| Date | Rating | Distance | Path | Fatalities |
| May 25, 2008 | EF5 | 57 km | 41.0 mi | 9 |
| Jun 13, 1976 | EF5 | 81 km | 21.3 mi | 0 |
| May 15, 1968 | EF5 | 84 km | 62.1 mi | 13 |
| May 30, 1989 | EF4 | 35 km | 11.0 mi | 0 |
| May 24, 1989 | EF4 | 78 km | 66.0 mi | 0 |
| Sep 28, 1986 | EF4 | 66 km | 20.0 mi | 0 |
| Aug 12, 1974 | EF4 | 68 km | 2.0 mi | 0 |
| Jun 18, 1974 | EF4 | 68 km | 15.3 mi | 2 |
| Aug 26, 1965 | EF4 | 65 km | 4.7 mi | 1 |
| Sep 1, 1961 | EF4 | 83 km | 26.6 mi | 0 |
| Apr 30, 1954 | EF4 | 96 km | 80.4 mi | 0 |
| Jul 19, 2018 | EF3 | 11 km | 8.4 mi | 0 |
| Jul 19, 2018 | EF3 | 64 km | 9.2 mi | 0 |
| Jun 22, 2015 | EF3 | 98 km | 11.1 mi | 0 |
| May 25, 2008 | EF3 | 96 km | 32.0 mi | 0 |
| Nov 12, 2005 | EF3 | 98 km | 17.6 mi | 1 |
| May 21, 2004 | EF3 | 90 km | 3.0 mi | 0 |
| May 11, 2000 | EF3 | 66 km | 18.6 mi | 1 |
| Mar 22, 1991 | EF3 | 62 km | 43.0 mi | 0 |
| Jun 28, 1990 | EF3 | 70 km | 9.0 mi | 0 |
Source: NOAA Storm Prediction Center (EF0+, 1950–2024, US only).
Wildfire History
5 wildfires (100+ acres) recorded within 100 km. Largest: NEAL SMITH WUI 2016 1 (1,050 acres, 2016).
| Year | Name | Acres Burned | Distance |
| 2016 | NEAL SMITH WUI 2016 1 | 1,050 | 59 km |
| 2009 | UNNAMED | 939 | 57 km |
| 2010 | FOLEY | 786 | 60 km |
| 2011 | ACE AUTO | 676 | 70 km |
| 2011 | IRCP WUI ROFAE #2 FY11 | 510 | 50 km |
Source: NIFC/IRWIN Wildfire Records (100+ acres).
Monthly Weather
| Month | Avg Temperature | Precipitation | Summary |
|---|---|---|---|
| January | 18°F (-8°C) | 0.9 in | Coldest, Driest |
| February | 24°F (-5°C) | 1.1 in | |
| March | 36°F (2°C) | 2.2 in | |
| April | 49°F (9°C) | 3.2 in | |
| May | 60°F (16°C) | 4.1 in | |
| June | 70°F (21°C) | 4.7 in | Wettest |
| July | 73°F (23°C) | 4.2 in | Warmest |
| August | 71°F (22°C) | 4.4 in | |
| September | 63°F (17°C) | 3.6 in | |
| October | 51°F (11°C) | 2.6 in | |
| November | 36°F (2°C) | 1.8 in | |
| December | 22°F (-5°C) | 1.3 in |
Marshalltown has a seasonal temperature swing of 55°F / from 18°F in January to 73°F in July. Total annual precipitation is 34.1 inches, with June being the wettest month (4.7") and January the driest (0.9").