Temperature, precipitation, air quality, natural hazards, and monthly weather data.
Rockville experiences four distinct seasons with an average annual temperature of 51°F (11°C). Winters average 27°F in January while summers reach 74°F in July. Annual precipitation totals 47.1 inches (wetter than the 38-inch national average). The area receives 51.7 inches of snow annually, making winter weather a significant factor for residents. The city sits at an elevation of 393 feet.
Temperature
27°F Jan (-3°C)74°F Jul (24°C)
Annual Average
51.0°F
6% below US avg
January Average
27°F (-3°C)
July Average
74°F (24°C)
Geography
Elevation
393 ft (120 m)
Area
1.8 sq mi (4.8 km²)
Population Density
3,618/sq mi
Coordinates
41.8665°N, 72.4513°W
Timezone
America/New_York
County
Capitol Planning Region County
Nearest Airport
Bradley International (BDL) 13 miles away
Precipitation & Snow
Annual Rainfall47.1"
24% above US avg
Snowfall51.7"
Wettest Month (Oct)4.52"
Driest Month (Feb)3.13"
Air Quality
Natural Hazard Risk
Overall Risk
Relatively High
Risk Score
97.4 / 100
Social Vulnerability
28.1 / 100
Community Resilience
64.2 / 100
Hazard Breakdown
Tornado
Relatively High
Hurricane
Relatively High
Earthquake
Relatively Moderate
Wildfire
Very Low
Flood
Relatively High
Hail
Relatively Moderate
Strong Wind
Relatively Moderate
Heat Wave
Relatively Moderate
Winter Weather
Relatively High
Lightning
Relatively High
Ice Storm
Very High
Drought
Relatively Low
Cold Wave
Relatively High
Landslide
Relatively Moderate
Coastal Flood
Very Low
Source: FEMA National Risk Index v1.20 (Dec 2025)
Earthquake History
17 earthquakes (M2.5+) recorded within 150 km since 1990.
Strongest on record: M3.7.
Oct 2, 1994
6 km W of Hardwick, Massachusetts
M3.7
55 km
10 km
Oct 2, 1994
1 km NW of Hardwick, Massachusetts
M3.3
58 km
10 km
Jun 16, 2000
5 km NE of Granville, Massachusetts
M3.3
40 km
10 km
Jan 12, 2015
0 km NE of Wauregan, Connecticut
M3.3
47 km
5 km
Mar 22, 1996
2 km NE of Bristol, Rhode Island
M3.1
102 km
12 km
Oct 28, 1991
3 km WNW of Stamford, Connecticut
M3.0
129 km
10 km
Mar 10, 1992
2 km SW of Napeague, New York
M2.8
102 km
10 km
Sep 28, 2002
2 km N of Wilton, New Hampshire
M2.8
126 km
5 km
Apr 12, 1991
2 km ENE of North Castle, New York
M2.7
128 km
9 km
Oct 13, 1999
2 km E of Littleton Common, Massachusetts
M2.7
113 km
2 km
Sep 30, 1991
0 km SSE of Bedford, New Hampshire
M2.7
142 km
4 km
Aug 14, 2014
6 km SW of Deep River Center, Connecticut
M2.7
58 km
4 km
Apr 22, 1996
3 km NE of North Westport, Massachusetts
M2.6
117 km
5 km
Jan 13, 2015
2 km E of Wauregan, Connecticut
M2.6
49 km
9 km
Aug 22, 2000
2 km WSW of Brewster Hill, New York
M2.6
110 km
7 km
Jun 7, 2002
3 km NNW of Hopedale, Massachusetts
M2.5
81 km
5 km
Jan 23, 1990
3 km NNW of Boxborough, Massachusetts
M2.5
105 km
5 km
Source: USGS Earthquake Catalog (M2.5+, 1990-2025). Sorted by magnitude.
Hurricane History
3 hurricanes (Category 1+) recorded within 500 km since 1980.
Strongest on record: Category 2.
Year
Name
Category
Max Wind
Closest
2014
Arthur
Category 1
75 mph
296 km
1991
Bob
Category 2
104 mph
102 km
1985
Gloria
Category 1
86 mph
29 km
Source: NOAA IBTrACS (Category 1+, 1980-2026).
Tornado History
258 tornadoes (EF0+) recorded within 100 km since 1950.
Strongest on record: EF4. Total: 107 fatalities, 2,208 injuries.
Date
Rating
Distance
Path
Fatalities
May 29, 1995
EF4
89 km
11.5 mi
3
Jul 10, 1989
EF4
66 km
3.0 mi
0
Oct 3, 1979
EF4
18 km
11.3 mi
3
Jun 9, 1953
EF4
71 km
34.9 mi
94
Jun 1, 2011
EF3
36 km
37.6 mi
3
Jun 22, 1981
EF3
79 km
7.1 mi
0
Sep 13, 1971
EF3
55 km
0.5 mi
0
Jul 29, 1971
EF3
61 km
0.1 mi
0
Oct 3, 1970
EF3
57 km
35.4 mi
1
May 24, 1962
EF3
66 km
11.6 mi
1
May 10, 1954
EF3
6 km
0.3 mi
0
Jun 9, 1953
EF3
66 km
28.0 mi
0
Aug 21, 1951
EF3
32 km
0.1 mi
0
Aug 18, 2023
EF2
73 km
9.1 mi
0
Jul 11, 2006
EF2
76 km
2.9 mi
0
Jun 23, 2001
EF2
56 km
0.5 mi
0
Aug 8, 1999
EF2
97 km
4.0 mi
0
Jul 3, 1997
EF2
69 km
3.7 mi
0
Jul 3, 1997
EF2
100 km
1.5 mi
0
Jul 3, 1997
EF2
72 km
4.5 mi
0
Source: NOAA Storm Prediction Center (EF0+, 1950-2024, US only).
Tsunami History
1 tsunami recorded within 500 km.
Highest wave on record: 0.3 m (1 ft).
Year
Location
Cause
Max Wave
Deaths
Distance
1964
LONG ISLAND, NY
Meteorological
0.3 m
-
130 km
Source: NOAA/NCEI Historical Tsunami Database.
Wildfire History
1 wildfire (100+ acres) recorded within 100 km.
Largest: THE RANGE (760 acres, 2005).
Year
Name
Acres Burned
Distance
2005
THE RANGE
760
96 km
Source: NIFC/IRWIN Wildfire Records (100+ acres).
Monthly Weather
Month
Avg Temperature
Precipitation
Summary
January
27°F (-3°C)
3.3 in
Coldest
February
30°F (-1°C)
3.1 in
Driest
March
38°F (3°C)
3.8 in
April
50°F (10°C)
3.9 in
May
60°F (16°C)
3.8 in
June
69°F (21°C)
4.3 in
July
74°F (24°C)
4.2 in
Warmest
August
73°F (23°C)
4.2 in
September
65°F (18°C)
4.4 in
October
53°F (12°C)
4.5 in
Wettest
November
42°F (6°C)
3.5 in
December
33°F (0°C)
4.1 in
Rockville has a seasonal temperature swing of 47°F / from 27°F in January to 74°F in July. Total annual precipitation is 47.1 inches, with October being the wettest month (4.5") and February the driest (3.1").