Colchester, IL

Full City Profile · Illinois · McDonough County County

3.1 /5.0

B Good

1,057 Population 919/sq mi density

$62,500 Median Income $31,944 per capita

$86,500 Home Value $98,597 Zillow

$808 Median Rent 39.7% income on rent

52°F Avg Temperature 275 sunny days/yr

78 Violent Crime/100K 544 property/100K

Overall

3.1 / 5.0

Good overall score based on economy, affordability, safety and education

Economy

4.1 / 5.0

$62,500 median income, 3.1% unemployment

A+

Affordability

5.0 / 5.0

$86,500 home value, $808/mo rent

Safety

1.0 / 5.0

78 violent crimes/100K

Education

2.5 / 5.0

18.7% bachelor's degree or higher

Colchester experiences four distinct seasons with an average annual temperature of 52°F (11°C). Winters average 25°F in January while summers reach 75°F in July. The area gets 275 sunny days per year. Annual precipitation totals 40.9 inches. Air quality is rated Good with a median AQI of 43.

Temperature

25°F Jan (-4°C) 75°F Jul (24°C)

Annual Average	51.7°F
	4% below US avg
January Average	25°F (-4°C)
July Average	75°F (24°C)
Sunny Days	275 days/yr

Geography

Elevation	696 ft (212 m)
Area	1.2 sq mi (3.0 km²)
Population Density	919/sq mi
Coordinates	40.4256°N, 90.7922°W
Timezone	America/Chicago
County	McDonough County County
Nearest Airport	Southeast Iowa Regional (BRL) 30 miles away

Precipitation & Snow

Annual Rainfall 40.9"

8% above US avg

Wettest Month (May) 4.17"

Driest Month (Feb) 1.38"

Air Quality

AQI Median	43.0
Rating	Good

Natural Hazard Risk

Overall Risk	Very Low
Risk Score	37.5 / 100
Social Vulnerability	61.9 / 100
Community Resilience	74.3 / 100

Hazard Breakdown

Tornado	Relatively Low
Hurricane	Very Low
Earthquake	Relatively Low
Wildfire	Very Low
Flood	Very Low
Hail	Relatively Moderate
Strong Wind	Relatively Moderate
Heat Wave	Relatively Moderate
Winter Weather	Relatively Low
Lightning	Relatively Low
Ice Storm	Relatively Moderate
Drought	Relatively Moderate
Cold Wave	Relatively Moderate
Landslide	Very Low

Source: FEMA National Risk Index v1.20 (Dec 2025)

Earthquake History

1 earthquake (M2.5+) within 150 km since 1990. Strongest: M2.9. Most recent: M2.9 on Feb 8, 2004.

Feb 8, 2004	6 km SSW of Stoutsville, Missouri	M2.9	139 km

Source: USGS (M2.5+, 1990–2025)

Tornado History

518 tornadoes (EF0+) within 100 km since 1950. Strongest: EF4. Total: 10 fatalities, 452 injuries.

Date	Rating	Distance	Fatalities
May 13, 1995	EF4	42 km	0
May 13, 1995	EF4	47 km	0
Jun 29, 1976	EF4	97 km	0
Apr 4, 2023	EF3	41 km	0
Dec 31, 2010	EF3	93 km	0
Jun 1, 2007	EF3	100 km	0
May 10, 2003	EF3	94 km	0
Apr 8, 1999	EF3	56 km	0
May 13, 1995	EF3	73 km	0
Jun 21, 1981	EF3	26 km	1
Aug 15, 1978	EF3	94 km	0
Jul 23, 1975	EF3	42 km	0
Jul 23, 1975	EF3	54 km	2
Jun 13, 1975	EF3	54 km	0
Apr 13, 1974	EF3	61 km	0
Sep 30, 1973	EF3	25 km	0
May 1, 1973	EF3	79 km	2
May 15, 1968	EF3	84 km	0
Jan 24, 1967	EF3	59 km	1
Jan 24, 1967	EF3	52 km	1

Source: NOAA SPC (EF0+, 1950–2024)

Wildfire History

5 wildfires (100+ acres) within 100 km. Largest: UNIT 3 (1,206 ac, 1999).

Year	Name	Acres	Distance
1999	UNIT 3	1,206	80 km
2002	HSB 03 2	1,130	81 km
2000	DESTRUST A	756	82 km
2006	HSB 003	674	80 km
2004	HSB 009	608	81 km

Source: NIFC/IRWIN (100+ acres)

Monthly Weather

Month	Avg Temperature	Precipitation	Summary
January	25°F (-4°C)	1.4 in	Coldest
February	29°F (-2°C)	1.4 in	Driest
March	40°F (5°C)	2.9 in
April	52°F (11°C)	3.7 in
May	62°F (17°C)	4.2 in	Wettest
June	72°F (22°C)	4.0 in
July	75°F (24°C)	4.2 in	Warmest
August	74°F (23°C)	3.5 in
September	66°F (19°C)	4.0 in
October	54°F (12°C)	3.0 in
November	41°F (5°C)	2.7 in
December	29°F (-2°C)	2.2 in

Colchester has a seasonal temperature swing of 50°F / from 25°F in January to 75°F in July. Total annual precipitation is 37.2 inches, with May being the wettest month (4.2") and February the driest (1.4").

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