Temperature, precipitation, air quality, natural hazards, and monthly weather data.
Marmora enjoys a temperate climate with an average annual temperature of 57°F (14°C). Winters average 37°F in January while summers reach 78°F in July. The area gets 297 sunny days per year, well above the U.S. average of 205 / making it one of the sunnier locations in the country. Air quality is rated Good with a median AQI of 39. The city sits at an elevation of 15 feet.
Temperature
37°F Jan (3°C)78°F Jul (26°C)
Annual Average
56.9°F
5% above US avg
January Average
37°F (3°C)
July Average
78°F (26°C)
Sunny Days
297 days/yr
Geography
Elevation
15 ft (5 m)
Area
2.0 sq mi (5.2 km²)
Population Density
1,001/sq mi
Coordinates
39.2587°N, 74.6574°W
Timezone
America/New_York
County
Atlantic County County
Nearest Airport
Atlantic City International (ACY) 14 miles away
Precipitation & Snow
Wettest Month (Aug)4.33"
Driest Month (Jun)2.91"
Air Quality
AQI Median
39.0
Rating
Good
Natural Hazard Risk
Overall Risk
Relatively Moderate
Risk Score
93.0 / 100
Social Vulnerability
46.5 / 100
Community Resilience
83.0 / 100
Hazard Breakdown
Tornado
Relatively Low
Hurricane
Relatively High
Earthquake
Relatively Low
Wildfire
Relatively Moderate
Flood
Relatively Moderate
Hail
Relatively Low
Strong Wind
Very High
Heat Wave
Relatively Moderate
Winter Weather
Very High
Lightning
Relatively High
Ice Storm
Relatively Moderate
Drought
Relatively Moderate
Cold Wave
Relatively Moderate
Landslide
Very Low
Coastal Flood
Very High
Source: FEMA National Risk Index v1.20 (Dec 2025)
Earthquake History
7 earthquakes (M2.5+) recorded within 150 km since 1990.
Strongest on record: M3.2.
Oct 23, 1990
3 km W of Hancocks Bridge, New Jersey
M3.2
78 km
10 km
Jan 9, 1992
4 km WNW of Robertsville, New Jersey
M3.1
126 km
8 km
Jul 1, 2009
3 km ESE of Pennsville, New Jersey
M2.8
83 km
5 km
Jan 25, 2015
4 km ESE of Downingtown, Pennsylvania
M2.6
119 km
2 km
Jul 5, 1996
2 km NW of Chester Heights, Pennsylvania
M2.6
102 km
18 km
Feb 9, 2023
29 km E of Greenbackville, Virginia
M2.6
141 km
11 km
Feb 26, 1993
2 km SW of Marlton, New Jersey
M2.5
73 km
5 km
Source: USGS Earthquake Catalog (M2.5+, 1990-2025). Sorted by magnitude.
Hurricane History
9 hurricanes (Category 1+) recorded within 500 km since 1980.
Strongest on record: Category 3.
Year
Name
Category
Max Wind
Closest
2014
Arthur
Category 1
92 mph
210 km
2012
Sandy
Category 2
92 mph
165 km
2011
Irene
Category 1
75 mph
132 km
2010
Earl
Category 1
81 mph
283 km
1998
Bonnie
Category 1
75 mph
286 km
1993
Emily
Category 3
115 mph
254 km
1991
Bob
Category 3
109 mph
149 km
1986
Charley
Category 1
75 mph
212 km
1985
Gloria
Category 2
98 mph
97 km
Source: NOAA IBTrACS (Category 1+, 1980-2026).
Tornado History
163 tornadoes (EF0+) recorded within 100 km since 1950.
Strongest on record: EF3. Total: 3 fatalities, 143 injuries.
Date
Rating
Distance
Path
Fatalities
Sep 1, 2021
EF3
69 km
12.4 mi
0
Jul 21, 1983
EF3
56 km
0.2 mi
0
Apr 28, 1961
EF3
91 km
0.3 mi
0
Jul 29, 2021
EF2
68 km
4.2 mi
0
Aug 4, 2020
EF2
75 km
35.8 mi
0
Aug 4, 2020
EF2
95 km
20.8 mi
0
Sep 28, 2004
EF2
94 km
5.0 mi
0
Aug 20, 1999
EF2
48 km
0.4 mi
0
Sep 27, 1993
EF2
99 km
10.0 mi
0
Aug 21, 1993
EF2
44 km
1.5 mi
0
Jul 31, 1992
EF2
79 km
4.0 mi
0
Oct 18, 1990
EF2
98 km
1.0 mi
0
May 10, 1990
EF2
40 km
0.5 mi
0
Jun 9, 1989
EF2
88 km
2.0 mi
0
Aug 17, 1988
EF2
87 km
1.5 mi
0
Jul 21, 1987
EF2
12 km
0.5 mi
0
Jul 18, 1984
EF2
95 km
1.5 mi
0
Jul 21, 1983
EF2
92 km
1.0 mi
2
Jun 29, 1982
EF2
77 km
1.5 mi
0
Sep 5, 1979
EF2
91 km
2.5 mi
0
Source: NOAA Storm Prediction Center (EF0+, 1950-2024, US only).
Tsunami History
1 tsunami recorded within 500 km.
Year
Location
Cause
Max Wave
Deaths
Distance
1840
PHILADELPHIA, PENNSYLVANIA
Earthquake
-
-
76 km
Source: NOAA/NCEI Historical Tsunami Database.
Wildfire History
20 wildfires (100+ acres) recorded within 100 km.
Largest: GREENWOOD STATE FOREST (21,271 acres, 1995).
Year
Name
Acres Burned
Distance
1995
GREENWOOD STATE FOREST
21,271
72 km
2007
WARREN GROVE
15,315
56 km
2022
MULLICA RIVER FIRE
13,082
48 km
1999
BASS RIVER
12,129
48 km
2019
SPRING HILL FIRE
8,182
62 km
2023
ALLEN ROAD
6,213
46 km
1992
FORKED RIVER MOUTAIN APR
5,093
74 km
1992
POWER PLANT
4,928
74 km
1992
UNNAMED
4,470
83 km
2024
TEA TIME HILL
4,444
59 km
2006
UNNAMED
3,780
51 km
2017
PENN SWAMP FIRE
3,587
47 km
2023
JIMMYS WATER HOLE
3,585
87 km
1989
SIMM PLACE
3,262
61 km
2002
UNNAMED
2,824
84 km
2007
ATSION
2,705
52 km
1992
FOUR MILE COLONY
2,647
68 km
1996
UNNAMED
2,625
47 km
2010
FORT DIX RANGE 1-14
2,615
85 km
1990
UNNAMED
2,367
58 km
Source: NIFC/IRWIN Wildfire Records (100+ acres).
Monthly Weather
Month
Avg Temperature
Precipitation
Summary
January
37°F (3°C)
3.5 in
February
36°F (2°C)
3.1 in
Coldest
March
43°F (6°C)
3.9 in
April
51°F (11°C)
3.5 in
May
61°F (16°C)
3.4 in
June
70°F (21°C)
2.9 in
Driest
July
78°F (26°C)
3.6 in
Warmest
August
74°F (24°C)
4.3 in
Wettest
September
68°F (20°C)
3.2 in
October
57°F (14°C)
3.0 in
November
48°F (9°C)
3.3 in
December
39°F (4°C)
3.4 in
Marmora has a seasonal temperature swing of 43°F / from 36°F in February to 78°F in July. Total annual precipitation is 41.1 inches, with August being the wettest month (4.3") and June the driest (2.9").