EF1 tornado, Strathmere to Marmora, New Jersey, August 4, 2020

1. EF065 to 85 mph

   Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.

2. EF186 to 110 mphthis tornado

   Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.

3. EF2111 to 135 mph

   Considerable damage. Roofs torn off well-built houses, frame homes shifted on their foundations, mobile homes destroyed, large trees snapped or uprooted, cars lifted off the ground.

4. EF3136 to 165 mph

   Severe damage. Whole stories of well-built houses destroyed, large buildings badly damaged, trains overturned, trees debarked, heavy cars lifted and thrown.

5. EF4166 to 200 mph

   Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.

6. EF5over 200 mph

   Incredible damage. Strong frame houses swept off their foundations, car-sized missiles thrown more than 100 meters, steel-reinforced concrete badly damaged, high-rise buildings deformed.

7. Unrated

   The survey recorded a tornado but could not put a number on it, most often because it crossed open country and damaged nothing a rating can be read from.

Rating

EF1

Date

August 4, 2020

Touchdown

9:45 AM EDT (13:45 UTC)

Lifted

9:50 AM EDT (13:50 UTC)

On the ground

5 minutes

Path length

4.2 miles (6.8 km)

Path width

150 yards (137 m)

Deaths

0

Injuries

0

County

Cape May County

Touchdown point

39.209, -74.648

Lift-off point

39.270, -74.660

Record number

2008040745-01

Tropical Storm Isaias brought high winds, heavy rain, several tornadoes, and coastal flooding to the mid-Atlantic region, becoming the most impactful tropical cyclone to impact most of the region since Sandy in 2012.

A waterspout came ashore near the southern end of Corson���s |Inlet State Park near Strathmere then across marshy areas. The |tornado then crossed the Garden State Parkway then tracked along |Route 9 across the south side of Marmora. There were several |pictures and videos of the waterspout and tornado including a |trained spotter reporting a tornado on the ground with debris in |the air. The tornado produced significant damage to homes and |businesses on the 500 block of Route 9, starting in the vicinity |of a Coca Cola facility where containers were tossed around with |even a truck trailer flipped onto its side. Adjacent to the Coca |Cola facility, a large shed at a residence was upended and |vehicles were moved from their original locations. Several homes |had portions of their roofs blown off with a couple of homes |sustaining significant damage to a side wall or corner walls. The |tornado crossed Route 9 to the Pine Hill Mobile Home Court where |significant damage occurred to trees and buildings. One home was |shifted off its foundation and others had roof damage and downed |trees crushed several cars. The tornado tracked north northwest |crossing Tuckahoe Road and may have dissipated over the adjacent |marsh areas. Doppler radar data showed a well defined tornado |debris signature as the tornado moved through portions of Marmora.

From NOAA NCEI's Storm Events Database, the narrative the local forecast office wrote for Storm Data.

No tornado warning for this county appears in the archive as in force at the moment the tornado touched down.

The county was under a tornado watch, issued at 06:27 UTC and running to 15:54 UTC.

Every warning and watch covering the touchdown point that day, from the Iowa Environmental Mesonet's archive of National Weather Service products. Lead time is measured from the issue of the warning in force to the touchdown time in the database, both of which were recorded to the minute by different people.

The Storm Prediction Center had this point in a Enhanced Risk, with a 0.10 chance of a tornado within 25 miles. The outlook in force was issued at 12:04 UTC.

SPC's Day 1 convective outlook as it stood when the tornado began, read at the touchdown point. The same archive is on the radar archive.

The radiosonde launches on either side of the tornado, from the nearest station that was launching then, drawn and analyzed the way Storm Lab does: the same diagram, the same parcel and shear definitions SPC's mesoanalysis uses.

The Philadelphia radar (KDIX), 81 km away, was scanning. The volume nearest the touchdown began at 13:42 UTC.

Open the radar archive at this moment, over the track

Reflectivity and velocity, decoded from the Level II archive in the browser. Volumes take a few seconds to open the first time.

Local storm reports within 60 km of the path, in the three hours either side.

From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.

The live radar over the trackEvery 2020 tornado in New JerseyEvery tornado in New Jersey since 1950Warnings in force in New Jersey nowThe forecast where you are

30 more were confirmed in the United States that day.

Ratings are the survey's, read off the damage rather than measured; the rating scale is above. Tornado counts rise through the record as reporting improved, so a year in the 1950s is not comparable with one today except for the strongest tornadoes, which were always noticed.

NOAA Storm Prediction Center tornado database, 1950-2025, the official record kept by NOAA's Storm Prediction Center.