Temperature, precipitation, air quality, natural hazards, and monthly weather data.
Decatur experiences four distinct seasons with an average annual temperature of 48°F (9°C). Winters average 24°F in January while summers reach 71°F in July. Annual precipitation totals 41.7 inches. The area receives 86.6 inches of snow annually, making winter weather a significant factor for residents. Air quality is rated Good with a median AQI of 45. 64% of days have good air quality. The city sits at an elevation of 790 feet.
Temperature
24°F Jan (-5°C)71°F Jul (22°C)
Annual Average
48.1°F
11% below US avg
January Average
24°F (-5°C)
July Average
71°F (22°C)
Geography
Elevation
790 ft (241 m)
Area
1.4 sq mi (3.5 km²)
Population Density
1,344/sq mi
Coordinates
42.1077°N, 85.9750°W
Timezone
America/Detroit
County
Kalamazoo County County
Nearest Airport
Southwest Michigan Regional (BEH) 23 miles away
Precipitation & Snow
Annual Rainfall41.7"
10% above US avg
Snowfall86.6"
Wettest Month (Oct)4.33"
Driest Month (Feb)2.41"
Air Quality
AQI Median
45.0
Rating
Good
Good Days %
63.9%
Unhealthy Days
0
Natural Hazard Risk
Overall Risk
Relatively Moderate
Risk Score
81.7 / 100
Social Vulnerability
18.5 / 100
Community Resilience
91.5 / 100
Hazard Breakdown
Tornado
Relatively High
Hurricane
Very Low
Earthquake
Relatively Low
Wildfire
Very Low
Flood
Relatively Moderate
Hail
Relatively High
Strong Wind
Relatively High
Heat Wave
Relatively Low
Winter Weather
Relatively Moderate
Lightning
Relatively Moderate
Ice Storm
Relatively Moderate
Drought
No Rating
Cold Wave
Relatively Moderate
Landslide
Relatively Low
Source: FEMA National Risk Index v1.20 (Dec 2025)
Earthquake History
4 earthquakes (M2.5+) recorded within 150 km since 1990.
Strongest on record: M4.2.
May 2, 2015
5 km S of Galesburg, Michigan
M4.2
47 km
4 km
Sep 2, 1994
5 km SSW of DeWitt, Michigan
M3.5
136 km
5 km
Jun 30, 2015
5 km NNE of Burlington, Michigan
M3.3
77 km
5 km
Jan 26, 2012
5 km NE of Topeka, Indiana
M3.0
72 km
5 km
Source: USGS Earthquake Catalog (M2.5+, 1990-2025). Sorted by magnitude.
Tornado History
367 tornadoes (EF0+) recorded within 100 km since 1950.
Strongest on record: EF5. Total: 159 fatalities, 2,142 injuries.
Date
Rating
Distance
Path
Fatalities
Apr 3, 1956
EF5
64 km
58.8 mi
17
Apr 2, 1977
EF4
86 km
16.6 mi
1
Apr 2, 1977
EF4
40 km
12.4 mi
0
Apr 11, 1965
EF4
88 km
80.5 mi
21
Apr 11, 1965
EF4
79 km
90.3 mi
23
Apr 11, 1965
EF4
59 km
21.6 mi
5
Apr 11, 1965
EF4
66 km
21.2 mi
31
Apr 11, 1965
EF4
62 km
37.0 mi
36
Oct 18, 2007
EF3
91 km
20.3 mi
0
Oct 24, 2001
EF3
66 km
47.0 mi
1
Mar 27, 1991
EF3
99 km
21.0 mi
1
Mar 27, 1991
EF3
94 km
2.0 mi
0
May 15, 1986
EF3
85 km
1.2 mi
0
May 13, 1980
EF3
24 km
21.0 mi
0
May 13, 1980
EF3
30 km
10.6 mi
5
Mar 12, 1976
EF3
94 km
12.6 mi
0
Apr 3, 1974
EF3
87 km
36.2 mi
5
Apr 21, 1967
EF3
90 km
13.6 mi
0
Nov 26, 1965
EF3
63 km
1.0 mi
0
Apr 11, 1965
EF3
43 km
14.2 mi
0
Source: NOAA Storm Prediction Center (EF0+, 1950-2024, US only).
Tsunami History
1 tsunami recorded within 500 km.
Highest wave on record: 3.0 m (10 ft).
Year
Location
Cause
Max Wave
Deaths
Distance
1954
MICHIGAN CITY, IN (LAKE MICHIGAN)
Avalanche
3.0 m
7
88 km
Source: NOAA/NCEI Historical Tsunami Database.
Wildfire History
1 wildfire (100+ acres) recorded within 100 km.
Largest: ALLEGAN6 (1,077 acres, 1988).
Year
Name
Acres Burned
Distance
1988
ALLEGAN6
1,077
52 km
Source: NIFC/IRWIN Wildfire Records (100+ acres).
Monthly Weather
Month
Avg Temperature
Precipitation
Summary
January
24°F (-5°C)
3.1 in
Coldest
February
26°F (-3°C)
2.4 in
Driest
March
35°F (2°C)
2.4 in
April
46°F (8°C)
3.7 in
May
58°F (14°C)
4.2 in
June
67°F (20°C)
4.3 in
July
71°F (22°C)
4.1 in
Warmest
August
69°F (21°C)
4.1 in
September
62°F (17°C)
3.4 in
October
50°F (10°C)
4.3 in
Wettest
November
39°F (4°C)
2.9 in
December
29°F (-1°C)
2.8 in
Decatur has a seasonal temperature swing of 47°F / from 24°F in January to 71°F in July. Total annual precipitation is 41.7 inches, with October being the wettest month (4.3") and February the driest (2.4").