Temperature, precipitation, air quality, natural hazards, and monthly weather data.
Riverwoods experiences four distinct seasons with an average annual temperature of 51°F (10°C). Winters average 25°F in January while summers reach 75°F in July. The area gets 260 sunny days per year, above the national average. Annual precipitation totals 32.3 inches. Air quality is rated Good with a median AQI of 43. The city sits at an elevation of 682 feet.
Temperature
25°F Jan (-4°C)75°F Jul (24°C)
Annual Average
50.8°F
6% below US avg
January Average
25°F (-4°C)
July Average
75°F (24°C)
Sunny Days
260 days/yr
Geography
Elevation
682 ft (208 m)
Area
1.6 sq mi (4.0 km²)
Population Density
1,005/sq mi
Coordinates
42.1729°N, 87.8949°W
Timezone
America/Chicago
County
Lake County County
Nearest Airport
Chicago O'Hare International (ORD) 14 miles away
Precipitation & Snow
Annual Rainfall32.3"
15% below US avg
Wettest Month (Aug)4.06"
Driest Month (Feb)1.30"
Air Quality
AQI Median
43.0
Rating
Good
Natural Hazard Risk
Overall Risk
Relatively High
Risk Score
96.0 / 100
Social Vulnerability
14.1 / 100
Community Resilience
78.1 / 100
Hazard Breakdown
Tornado
Very High
Hurricane
Very Low
Earthquake
Relatively Low
Wildfire
Very Low
Flood
Relatively High
Hail
Relatively Moderate
Strong Wind
Very High
Heat Wave
Relatively Moderate
Winter Weather
Relatively Moderate
Lightning
Relatively High
Ice Storm
Relatively Moderate
Drought
Relatively Low
Cold Wave
Very High
Landslide
Very Low
Coastal Flood
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
115 km
10 km
Feb 10, 2010
2 km NW of Lily Lake, Illinois
M3.8
55 km
10 km
Sep 2, 1999
8 km W of Amboy, Illinois
M3.5
137 km
5 km
Nov 4, 2013
1 km SSW of Lyons, Illinois
M3.2
42 km
1 km
Jul 15, 2024
2 km WNW of Somonauk, Illinois
M3.1
89 km
10 km
Mar 25, 2015
3 km WNW of Lake in the Hills, Illinois
M2.9
39 km
6 km
Jun 10, 2013
4 km NNE of Virgil, Illinois
M2.6
55 km
5 km
Mar 15, 2025
6 km W of Dwight, Illinois
M2.6
131 km
5 km
Source: USGS Earthquake Catalog (M2.5+, 1990–2025). Sorted by magnitude.
Tornado History
495 tornadoes (EF0+) recorded within 100 km since 1950.
Strongest on record: EF5. Total: 105 fatalities, 2,236 injuries.
Date
Rating
Distance
Path
Fatalities
Aug 28, 1990
EF5
67 km
16.4 mi
29
Apr 27, 1984
EF4
98 km
6.5 mi
1
Jun 29, 1979
EF4
78 km
5.4 mi
0
Jun 13, 1976
EF4
57 km
3.3 mi
2
Sep 28, 1972
EF4
12 km
5.2 mi
0
Apr 21, 1967
EF4
56 km
15.0 mi
33
Apr 21, 1967
EF4
31 km
8.8 mi
1
Apr 21, 1967
EF4
85 km
25.5 mi
24
Apr 11, 1965
EF4
40 km
9.1 mi
6
Jun 20, 2021
EF3
54 km
17.6 mi
0
Jan 7, 2008
EF3
55 km
10.8 mi
0
Jan 7, 2008
EF3
81 km
13.2 mi
0
Mar 27, 1991
EF3
68 km
15.0 mi
0
Apr 27, 1984
EF3
78 km
9.0 mi
1
Mar 12, 1976
EF3
93 km
12.6 mi
0
Mar 12, 1976
EF3
71 km
22.6 mi
0
Oct 24, 1967
EF3
89 km
0.1 mi
0
Nov 12, 1965
EF3
77 km
4.1 mi
0
Jul 19, 1963
EF3
54 km
10.6 mi
0
Apr 23, 1961
EF3
95 km
51.7 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
99 km
Source: NOAA/NCEI Historical Tsunami Database.
Wildfire History
12 wildfires (100+ acres) recorded within 100 km.
Largest: UNNAMED (1,741 acres, 2019).
Year
Name
Acres Burned
Distance
2019
UNNAMED
1,741
91 km
2019
UNNAMED
1,664
91 km
2021
NORTHEAST PRAIRIE UNIT 3
978
90 km
2024
NORTHEAST PRAIRIE 3 RX
938
89 km
1986
OGDEN DUNS
863
84 km
2021
UNNAMED
738
88 km
2021
MIDDLE GRANT CREEK
700
92 km
2019
UNNAMED
698
88 km
2024
IBSP SOUTH F1 RX
690
27 km
2021
21-INDU TOLLESTON DUNES EAST
594
85 km
2017
UNNAMED
549
92 km
2017
17 INDU COWLES DUNES
522
88 km
Source: NIFC/IRWIN Wildfire Records (100+ acres).
Monthly Weather
Month
Avg Temperature
Precipitation
Summary
January
25°F (-4°C)
1.7 in
Coldest
February
26°F (-3°C)
1.3 in
Driest
March
36°F (2°C)
2.5 in
April
47°F (8°C)
3.5 in
May
58°F (14°C)
3.4 in
June
67°F (20°C)
3.7 in
July
75°F (24°C)
3.7 in
Warmest
August
71°F (22°C)
4.1 in
Wettest
September
63°F (17°C)
3.7 in
October
52°F (11°C)
2.4 in
November
39°F (4°C)
2.6 in
December
27°F (-3°C)
2.2 in
Riverwoods has a seasonal temperature swing of 50°F / from 25°F in January to 75°F in July. Total annual precipitation is 34.8 inches, with August being the wettest month (4.1") and February the driest (1.3").