Temperature, precipitation, air quality, natural hazards, and monthly weather data.
Elgin experiences four distinct seasons with an average annual temperature of 49°F (9°C). Winters average 22°F in January while summers reach 74°F in July. Annual precipitation totals 39.9 inches. The area receives 32.1 inches of snow annually, a moderate snowfall amount. Air quality is rated Good with a median AQI of 43. 67% of days have good air quality. The city sits at an elevation of 817 feet.
Temperature
22°F Jan (-6°C)74°F Jul (23°C)
Annual Average
49.0°F
9% below US avg
January Average
22°F (-6°C)
July Average
74°F (23°C)
Geography
Elevation
817 ft (249 m)
Area
37.7 sq mi (97.7 km²)
Population Density
2,989/sq mi
Coordinates
42.0390°N, 88.3257°W
Timezone
America/Chicago
County
McHenry County County
Nearest Airport
Chicago O'Hare International (ORD) 22 miles away
Precipitation & Snow
Annual Rainfall39.9"
5% above US avg
Snowfall32.1"
Wettest Month (May)5.12"
Driest Month (Feb)1.87"
Air Quality
AQI Median
43.0
Rating
Good
Good Days %
66.9%
Unhealthy Days
1
Natural Hazard Risk
Overall Risk
Relatively Moderate
Risk Score
90.8 / 100
Social Vulnerability
10.6 / 100
Community Resilience
84.0 / 100
Hazard Breakdown
Tornado
Relatively High
Hurricane
Very Low
Earthquake
Relatively Low
Wildfire
Very Low
Flood
Relatively Moderate
Hail
Relatively Moderate
Strong Wind
Relatively High
Heat Wave
Relatively Low
Winter Weather
Relatively Moderate
Lightning
Relatively Moderate
Ice Storm
Relatively Low
Drought
Relatively Low
Cold Wave
Relatively High
Landslide
Very Low
Source: FEMA National Risk Index v1.20 (Dec 2025)
Earthquake History
8 earthquakes (M2.5+) recorded within 150 km since 1990.
Strongest on record: M4.2.
Jun 28, 2004
12 km NW of Dayton, Illinois
M4.2
80 km
10 km
Feb 10, 2010
2 km NW of Lily Lake, Illinois
M3.8
16 km
10 km
Sep 2, 1999
8 km W of Amboy, Illinois
M3.5
98 km
5 km
Nov 4, 2013
1 km SSW of Lyons, Illinois
M3.2
49 km
1 km
Jul 15, 2024
2 km WNW of Somonauk, Illinois
M3.1
54 km
10 km
Mar 25, 2015
3 km WNW of Lake in the Hills, Illinois
M2.9
17 km
6 km
Jun 10, 2013
4 km NNE of Virgil, Illinois
M2.6
16 km
5 km
Mar 15, 2025
6 km W of Dwight, Illinois
M2.6
107 km
5 km
Source: USGS Earthquake Catalog (M2.5+, 1990-2025). Sorted by magnitude.
Tornado History
583 tornadoes (EF0+) recorded within 100 km since 1950.
Strongest on record: EF5. Total: 110 fatalities, 2,202 injuries.
Date
Rating
Distance
Path
Fatalities
Aug 28, 1990
EF5
40 km
16.4 mi
29
Apr 9, 2015
EF4
82 km
30.1 mi
2
Jun 29, 1979
EF4
58 km
5.4 mi
0
Jun 13, 1976
EF4
49 km
3.3 mi
2
Sep 28, 1972
EF4
46 km
5.2 mi
0
Apr 21, 1967
EF4
58 km
15.0 mi
33
Apr 21, 1967
EF4
53 km
25.5 mi
24
Apr 21, 1967
EF4
13 km
8.8 mi
1
Apr 11, 1965
EF4
21 km
9.1 mi
6
Apr 17, 1963
EF4
97 km
57.3 mi
1
Jun 20, 2021
EF3
34 km
17.6 mi
0
Feb 28, 2017
EF3
95 km
11.5 mi
2
Jun 22, 2015
EF3
81 km
16.3 mi
0
Jan 7, 2008
EF3
57 km
10.8 mi
0
Jan 7, 2008
EF3
57 km
13.2 mi
0
Mar 27, 1991
EF3
54 km
15.0 mi
0
Apr 27, 1984
EF3
54 km
9.0 mi
1
Jun 30, 1977
EF3
76 km
6.1 mi
0
Mar 12, 1976
EF3
46 km
22.6 mi
0
Nov 12, 1965
EF3
89 km
4.1 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
125 km
Source: NOAA/NCEI Historical Tsunami Database.
Wildfire History
9 wildfires (100+ acres) recorded within 100 km.
Largest: UNNAMED (1,741 acres, 2019).
Year
Name
Acres Burned
Distance
2019
UNNAMED
1,741
75 km
2019
UNNAMED
1,664
77 km
2021
NORTHEAST PRAIRIE UNIT 3
978
79 km
2024
NORTHEAST PRAIRIE 3 RX
938
77 km
2021
UNNAMED
738
76 km
2021
MIDDLE GRANT CREEK
700
76 km
2019
UNNAMED
698
76 km
2024
IBSP SOUTH F1 RX
690
59 km
2017
UNNAMED
549
76 km
Source: NIFC/IRWIN Wildfire Records (100+ acres).
Monthly Weather
Month
Avg Temperature
Precipitation
Summary
January
22°F (-6°C)
2.0 in
Coldest
February
26°F (-4°C)
1.9 in
Driest
March
36°F (2°C)
2.4 in
April
48°F (9°C)
4.0 in
May
59°F (15°C)
5.1 in
Wettest
June
69°F (21°C)
4.5 in
July
74°F (23°C)
4.0 in
Warmest
August
72°F (22°C)
4.3 in
September
64°F (18°C)
3.5 in
October
52°F (11°C)
3.3 in
November
39°F (4°C)
2.7 in
December
28°F (-2°C)
2.2 in
Elgin has a seasonal temperature swing of 52°F / from 22°F in January to 74°F in July. Total annual precipitation is 39.9 inches, with May being the wettest month (5.1") and February the driest (1.9").