All Countries
Weather & Climate in Merrill, IA
Temperature, precipitation, air quality, natural hazards, and monthly weather data.
Merrill experiences four distinct seasons with an average annual temperature of 47°F (8°C). Winters average 17°F in January while summers reach 73°F in July. The area gets 291 sunny days per year, well above the U.S. average of 205 / making it one of the sunnier locations in the country. Annual precipitation totals 30.0 inches (drier than the 38-inch national average). The area receives 30.9 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 1,190 feet.
Temperature
17°F Jan (-8°C)
73°F Jul (23°C)
| Annual Average | 46.9°F |
| 13% below US avg | |
| January Average | 17°F (-8°C) |
| July Average | 73°F (23°C) |
| Sunny Days | 291 days/yr |
Geography
| Elevation | 1,190 ft (363 m) |
| Area | 0.6 sq mi (1.5 km²) |
| Population Density | 1,702/sq mi |
| Coordinates | 42.7205°N, 96.2519°W |
| Timezone | America/Chicago |
| County | Plymouth County County |
| Nearest Airport | Sioux Gateway/Brig General Bud Day Field (SUX) 23 miles away |
Precipitation & Snow
Air Quality
| AQI Median | 43.0 |
| Rating | Good |
Natural Hazard Risk
| Overall Risk | Relatively Low |
| Risk Score | 49.2 / 100 |
| Social Vulnerability | 26.2 / 100 |
| Community Resilience | 89.1 / 100 |
Hazard Breakdown
| Tornado | Relatively Moderate |
| Earthquake | Very Low |
| Wildfire | Relatively Low |
| Flood | Relatively Low |
| Hail | Relatively Moderate |
| Strong Wind | Relatively Low |
| Heat Wave | Relatively Low |
| Winter Weather | Relatively Moderate |
| Lightning | Relatively Low |
| Ice Storm | Relatively Moderate |
| Drought | Relatively Moderate |
| Cold Wave | Relatively Low |
| Landslide | Relatively Low |
Source: FEMA National Risk Index v1.20 (Dec 2025)
Earthquake History
5 earthquakes (M2.5+) recorded within 150 km since 1990. Strongest on record: M3.6.
| Feb 6, 1996 | 1 km N of Wausa, Nebraska | M3.6 | 108 km | 5 km |
| Aug 9, 1997 | 9 km NW of Clarkson, Nebraska | M3.4 | 128 km | 5 km |
| Jan 4, 2021 | 5 km N of Tyndall, South Dakota | M3.1 | 136 km | 5 km |
| Jun 30, 2021 | 4 km E of Rembrandt, Iowa | M2.7 | 94 km | 10 km |
| Mar 6, 2024 | 6 km SSE of Santee, Nebraska | M2.5 | 128 km | 5 km |
Source: USGS Earthquake Catalog (M2.5+, 1990–2025). Sorted by magnitude.
Tornado History
625 tornadoes (EF0+) recorded within 100 km since 1950. Strongest on record: EF4. Total: 8 fatalities, 133 injuries.
| Date | Rating | Distance | Path | Fatalities |
| Jun 16, 2014 | EF4 | 83 km | 15.8 mi | 0 |
| Oct 4, 2013 | EF4 | 95 km | 18.3 mi | 0 |
| Oct 4, 2013 | EF4 | 45 km | 24.7 mi | 0 |
| Jun 25, 2010 | EF4 | 84 km | 13.7 mi | 0 |
| Jun 23, 2003 | EF4 | 91 km | 13.0 mi | 1 |
| Jul 28, 1986 | EF4 | 59 km | 52.5 mi | 0 |
| Jul 7, 1977 | EF4 | 73 km | 22.6 mi | 0 |
| Jun 7, 1965 | EF4 | 94 km | 7.8 mi | 1 |
| Jun 23, 1952 | EF4 | 33 km | 24.1 mi | 0 |
| Jun 17, 2014 | EF3 | 85 km | 4.0 mi | 0 |
| Apr 9, 2011 | EF3 | 72 km | 3.4 mi | 0 |
| Apr 9, 2011 | EF3 | 95 km | 29.4 mi | 0 |
| Apr 9, 2011 | EF3 | 89 km | 10.1 mi | 0 |
| Aug 7, 1994 | EF3 | 90 km | 4.5 mi | 0 |
| Jul 5, 1994 | EF3 | 44 km | 1.8 mi | 0 |
| May 27, 1991 | EF3 | 95 km | 6.0 mi | 0 |
| Aug 3, 1981 | EF3 | 96 km | 12.8 mi | 0 |
| May 8, 1979 | EF3 | 31 km | 0.1 mi | 0 |
| Jul 5, 1978 | EF3 | 54 km | 8.0 mi | 0 |
| Oct 1, 1971 | EF3 | 72 km | 11.2 mi | 0 |
Source: NOAA Storm Prediction Center (EF0+, 1950–2024, US only).
Monthly Weather
| Month | Avg Temperature | Precipitation | Summary |
|---|---|---|---|
| January | 17°F (-8°C) | 0.6 in | Coldest, Driest |
| February | 23°F (-5°C) | 0.6 in | |
| March | 35°F (2°C) | 1.9 in | |
| April | 48°F (9°C) | 2.6 in | |
| May | 61°F (16°C) | 3.5 in | |
| June | 70°F (21°C) | 3.9 in | Wettest |
| July | 73°F (23°C) | 3.3 in | Warmest |
| August | 72°F (22°C) | 3.2 in | |
| September | 63°F (17°C) | 2.8 in | |
| October | 50°F (10°C) | 2.0 in | |
| November | 34°F (1°C) | 1.3 in | |
| December | 21°F (-6°C) | 0.8 in |
Merrill has a seasonal temperature swing of 56°F / from 17°F in January to 73°F in July. Total annual precipitation is 26.4 inches, with June being the wettest month (3.9") and January the driest (0.6").