Thornton, IA

Full City Profile · Iowa · Franklin County County

4.0 /5.0
A Great
534 Population 431/sq mi density
$66,979 Median Income $33,158 per capita
$99,000 Home Value $161,949 Zillow
$775 Median Rent 21.9% income on rent
46°F Avg Temperature
A
Overall
4.0 / 5.0
Strong
A
Economy
4.3 / 5.0
$66,979 median income, 2.5% unemployment
A+
Affordability
5.0 / 5.0
$99,000 home value, $775/mo rent
C+
Education
2.6 / 5.0
19.9% bachelor's degree or higher
Thornton experiences four distinct seasons with an average annual temperature of 46°F (8°C). Winters average 16°F in January while summers reach 72°F in July. Annual precipitation totals 36.2 inches. The area receives 44.4 inches of snow annually.

Temperature

16°F Jan (-9°C) 72°F Jul (22°C)
Annual Average45.6°F
16% below US avg
January Average16°F (-9°C)
July Average72°F (22°C)

Geography

Elevation1,191 ft (363 m)
Area1.2 sq mi (3.2 km²)
Population Density431/sq mi
Coordinates42.9442°N, 93.3870°W
TimezoneAmerica/Chicago
CountyFranklin County County
Nearest AirportNortheast Iowa Regional (CCY)
40 miles away

Precipitation & Snow

Annual Rainfall 36.2"
5% below US avg
Snowfall 44.4"
Wettest Month (Jun) 5.39"
Driest Month (Jan) 0.89"

Air Quality

Natural Hazard Risk

Overall RiskVery Low
Risk Score22.0 / 100
Social Vulnerability10.6 / 100
Community Resilience51.7 / 100

Hazard Breakdown

Tornado Relatively Low
Hurricane Very Low
Earthquake Very Low
Wildfire Very Low
Flood Very Low
Hail Relatively Low
Strong Wind Relatively Low
Heat Wave Very Low
Winter Weather Relatively Low
Lightning Very Low
Ice Storm Relatively Low
Drought Relatively High
Cold Wave Relatively Low
Landslide Very Low
Source: FEMA National Risk Index v1.20 (Dec 2025)

Earthquake History

2 earthquakes (M2.5+) within 150 km since 1990. Strongest: M2.8. Most recent: M2.7 on Jun 30, 2021.

Apr 25, 2017 Near Mankato, Minnesota M2.8 147 km
Jun 30, 2021 4 km E of Rembrandt, Iowa M2.7 141 km
Source: USGS (M2.5+, 1990-2025)

Tornado History

644 tornadoes (EF0+) within 100 km since 1950. Strongest: EF5. Total: 55 fatalities, 1,061 injuries.

Date Rating Distance Fatalities
May 25, 2008 EF5 60 km 9
May 15, 1968 EF5 29 km 13
Oct 14, 1966 EF5 27 km 6
Jun 17, 2010 EF4 73 km 1
May 30, 1989 EF4 76 km 0
May 24, 1989 EF4 87 km 0
May 4, 1977 EF4 78 km 0
Jul 12, 1971 EF4 83 km 0
Jun 8, 1967 EF4 80 km 0
Apr 30, 1967 EF4 96 km 6
Apr 30, 1967 EF4 70 km 5
Apr 30, 1967 EF4 59 km 0
Apr 30, 1967 EF4 43 km 0
May 5, 1965 EF4 59 km 0
Aug 29, 1964 EF4 69 km 0
Sep 1, 1961 EF4 36 km 0
May 10, 1953 EF4 98 km 2
May 10, 1953 EF4 18 km 0
Jun 12, 2013 EF3 25 km 0
Jun 17, 2010 EF3 84 km 0
Source: NOAA SPC (EF0+, 1950-2024)

Monthly Weather

Month Avg Temperature Precipitation Summary
January 16°F (-9°C) 0.9 in Coldest, Driest
February 20°F (-7°C) 1.2 in
March 33°F (0°C) 2.3 in
April 46°F (8°C) 4.2 in
May 58°F (15°C) 5.2 in
June 69°F (20°C) 5.4 in Wettest
July 72°F (22°C) 4.4 in Warmest
August 69°F (21°C) 3.8 in
September 61°F (16°C) 3.5 in
October 48°F (9°C) 2.5 in
November 34°F (1°C) 1.7 in
December 22°F (-6°C) 1.3 in

Thornton has a seasonal temperature swing of 56°F / from 16°F in January to 72°F in July. Total annual precipitation is 36.3 inches, with June being the wettest month (5.4") and January the driest (0.9").

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