Alert archive / New Jersey / Severe Thunderstorm Warnings in 2026

Severe Thunderstorm Warning 319, NWS Philadelphia/Mount Holly

August 20, 2026Atlantic County, Cape May County, Cumberland County, New Jersey

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Aug 20, 2026, 6:38 PM EDT for Atlantic County, Cape May County, Cumberland County, New Jersey. It was in force for 37 min. 3 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Aug 20, 2026, 6:38 PM EDT (22:38 UTC)
Expired
Aug 20, 2026, 7:15 PM EDT
In force
37 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Tornado
Possible
Hail
0.75 in
Wind
60.0 mph

Counties Atlantic County, NJ, Cape May County, NJ, Cumberland County, NJ

The radar

The Dover AFB radar (KDOX), 59 km from the middle of the area, began a volume at 22:39 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

What was reported inside it

TimeReportWhereRemark
Aug 20, 7:14 PM EDTTSTM WND DMG3 N Belleplain, NJReport of a tree down at the 47 mile post of Route 49 in Estell Manor. Time estimated from radar.
Aug 20, 7:16 PM EDTTSTM WND GST 671 Se Villas, NJAWOS station KWWD Wildwood.
Aug 20, 7:16 PM EDTMARINE TSTM WIND 671 Se Villas, NJAWOS station KWWD Wildwood.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

Did it verify

Verified. The Iowa Environmental Mesonet's Cow matched one storm report to this severe thunderstorm warning; the first came 36 minutes after it went out.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Aug 20, 2:31 PM EDTSevere Thunderstorm WatchSPC7 hr
Aug 20, 2:58 PM EDTTornado WatchSPC7 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 10.6 hours before the alert went out and 214 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Washington/Dulle, VA at 12:00Z on 2026-08-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 97 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Washington/Dulle, VA at 12:00Z on 2026-08-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 115 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
97 J/kg
Mixed-layer CIN
-72 J/kg
Mixed-layer LCL
1192 m above ground
0-6 km bulk shear
47 kt
0-1 km storm-relative helicity
115 m²/s²
0-3 km storm-relative helicity
230 m²/s²
Significant tornado parameter
-0.0
Supercell composite
-0.0

Open this sounding in Storm Lab

The text

As transmitted.

047 
WUUS51 KPHI 202238
SVRPHI
NJC001-009-011-202315-
/O.NEW.KPHI.SV.W.0319.260820T2238Z-260820T2315Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
Issued by National Weather Service New York NY
638 PM EDT Thu Aug 20 2026

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Southwestern Atlantic County in southern New Jersey...
  Cumberland County in southern New Jersey...
  Cape May County in southern New Jersey...

* Until 715 PM EDT.

* At 637 PM EDT, severe thunderstorms were located along a line
  extending from near Fairton to near Big Stone Beach, moving east at
  30 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

  IMPACT...Expect damage to trees and power lines.

* Locations impacted include...
  Vineland, Millville, Bridgeton, Ocean City, Cape May, Cumberland,
  Somers Point, North Wildwood, Laurel Lake, Wildwood Crest,
  Woodbine, Sea Isle City, Estell Manor, Avalon, and West Cape May.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 1000 PM EDT for southern New
Jersey.

Remain alert for a possible tornado! Tornadoes can develop quickly
from severe thunderstorms. If you spot a tornado go at once into the
basement or small central room in a sturdy structure.

For your protection move to an interior room on the lowest floor of a
building.

A Tornado Watch remains in effect until 1000 PM EDT for southern New
Jersey.

&&

LAT...LON 3920 7463 3898 7478 3893 7486 3893 7498
      3913 7491 3916 7493 3920 7510 3917 7515
      3923 7518 3928 7526 3928 7530 3944 7526
      3944 7465 3927 7457
TIME...MOT...LOC 2237Z 266DEG 26KT 3940 7520 3896 7530 

TORNADO...POSSIBLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

DeSilva
1 follow-up statement
095 
WWUS51 KPHI 202304
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
Issued by National Weather Service New York NY
704 PM EDT Thu Aug 20 2026

NJC001-009-011-202315-
/O.CON.KPHI.SV.W.0319.000000T0000Z-260820T2315Z/
Atlantic NJ-Cumberland NJ-Cape May NJ-
704 PM EDT Thu Aug 20 2026

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 715 PM EDT
FOR SOUTHWESTERN ATLANTIC...SOUTHEASTERN CUMBERLAND AND CAPE MAY
COUNTIES...

At 703 PM EDT, severe thunderstorms were located along a line
extending from near Dorothy to North Cape May, moving east at 40 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Expect damage to trees and power lines.

Locations impacted include...
Millville, Ocean City, Cape May, Cumberland, Somers Point, North
Wildwood, Laurel Lake, Wildwood Crest, Woodbine, Sea Isle City,
Estell Manor, Avalon, West Cape May, Stone Harbor, and Corbin City.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 1000 PM EDT for southern New
Jersey.

Remain alert for a possible tornado! Tornadoes can develop quickly
from severe thunderstorms. If you spot a tornado go at once into the
basement or small central room in a sturdy structure.

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 3920 7463 3898 7478 3893 7486 3893 7498
      3913 7491 3916 7493 3920 7510 3917 7515
      3925 7520 3938 7505 3941 7464 3927 7457
TIME...MOT...LOC 2303Z 255DEG 35KT 3941 7486 3897 7496 

TORNADO...POSSIBLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

DeSilva

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Philadelphia/Mount Holly wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 20, 4:23 PM EDT, 2 hours 15 minutes earlier. Its key messages:

  • 1. A cold front will cross the region this evening, resulting in widespread showers and thunderstorms. Flash flooding, damaging wind gusts and tornadoes are possible later today. 2. Conditions look to remain unsettled through the weekend, with daily chances of showers and storms each day. 3. Fair weather is expected to return for early next week.
Area forecast discussion, Aug 20, 4:23 PM EDT, 2 hours 15 minutes before
Area Forecast Discussion
National Weather Service Mount Holly NJ
423 PM EDT Thu Aug 20 2026

.WHAT HAS CHANGED...
Severe thunderstorm and tornado watches now in effect for most
of the forecast area.

&&

.KEY MESSAGES...
1. A cold front will cross the region this evening, resulting
in widespread showers and thunderstorms. Flash flooding,
damaging wind gusts and tornadoes are possible later today.

2. Conditions look to remain unsettled through the
weekend, with daily chances of showers and storms each day.

3. Fair weather is expected to return for early next week.

&&

.DISCUSSION...
KEY MESSAGE 1...Broad troughing will be the main driving force
in the sensible weather into the early to middle part of next
week across much of the Eastern Seaboard. A shortwave will round
the base of the trough today into this evening providing some
mid level synoptic forcing. At the surface a warm front has
lifted north into the Philadelphia metro area with a cold front
approaching from the west.

The trend for increasing QPF and increasing severe weather
potential is being realized this afternoon. Severe thunderstorm,
tornado, and flood watches are in effect for most of the
forecast area.

Mesoanalysis fields this afternoon show moderate to strong
instability centered roughly around the Delmarva peninsula, but
extending north into southern NJ and southeast PA. Deep layer
shear of 40-60kt along with backed low level flow and strongly
curved hodographs will support a tornado risk, most notably from
the Philadelphia metro area and points south. Primary mode at
the moment is supercellular with all attendant risks, but more
multicell clusters may become the primary mode along the cold
front.

The other threat this evening is the potential for flash
flooding. Guidance shows very moisture rich airmass surging into
the region with PWAT values raching 2-2.5 inches. Warm cloud
depths suggest warm rain processes and high precipitation
efficiency into this evening and WPC has introduced a moderate
risk of execessive reainfall from Philadelphia north and east.

In general, expecting anywhere between 1 to 2 inches of rain to
fall, with localized higher amounts up to 3 to 5 inches.

The severe and flooding rain threat will diminish by the late
evening and overnight hours.

KEY MESSAGE 2...Conditions look to remain unsettled through the
weekend, with daily chances of showers and storms each day.

Mid to long range NWP and AI guidance suggests that the pattern
could become unsettled Friday night and into the weekend.
The cold front crossing the area tonight will stall in the
offshore waters. waves of low pressure will ride along the
stalled front resulting in unsettled weather through the
weekend. The main periods to watch are early Saturday through
Saturday evening, with periods of rain increasingly likely, and
again on Sunday. The severe threat appears low at this time but
there could be additional flooding concerns, although no day
has more than a Marginal (1/5) Risk for excessive rainfall.

Temperatures will be seasonable, but humidity will be
uncomfortable.

KEY MESSAGE 3...Fair weather is expected to return for early
next week.

Weak high pressure looks to bring quieter and drier weather in
the early part of the week, with more unsettled conditions
expected later in the week with seasonable temperatures.

&&

.AVIATION /19Z THURSDAY THROUGH TUESDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY and surrounding areas.

Today...Widespread showers and thunderstorms are likely at all
locations this afternoon and evening. Any storms will be
capable of producing very heavy rainfall and LIFR conditions.
Winds will vary depending on location, with northern terminals
experiencing northeast winds 5 to 10 kt where southern
terminals will encounter southeasterly winds around 10 kt. Winds
will be gusty and erratic near any storm. Bulk of the shower and
storm activity ending around 01-02z. Moderate confidence
overall, but low confidence on exact timing details.

Tonight...Sub-VFR conditions probable at times with showers and
thunderstorms continuing into the evening hours. Fog and/or low
stratus possible at night after the precipitation moves out.
Conditions should lift back to VFR near or not long after
daybreak. North/northeast winds around 5 to 10 kt. Moderate
confidence.

Outlook...

Friday through Friday night...Primarily VFR.

Saturday through Sunday...Periods of VFR and sub-VFR at times.
Restrictions expected with daily chances for showers and
thunderstorms.

Monday...VFR. No significant weather expected.

&&

.MARINE...
A cold front will move through tonight, with winds becoming
more north/northeasterly around 10-15 kt. Seas of 2 to 3 feet.
Showers and thunderstorms expected on the waters this evening
into tonight.

Outlook...

Friday through Monday...No marine headlines expected. Showers
and thunderstorms possible during the day Friday through
Sunday.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...Flood Watch until 2 AM EDT Friday for PAZ054-055-060>062-070-
     071-101>106.
NJ...Flood Watch until 2 AM EDT Friday for NJZ001-007>010-012>022-
     025>027.
DE...Flood Watch until 2 AM EDT Friday for DEZ001.
MD...None.
MARINE...None.

&&

DISCUSSION...Manning
AVIATION...Manning
MARINE...Manning
Hazardous weather outlook, Aug 20, 5:12 AM EDT, 13 hours 26 minutes before
Hazardous Weather Outlook
National Weather Service Mount Holly NJ
512 AM EDT Thu Aug 20 2026

MDZ012-015-019-020-210915-
Kent MD-Queen Annes-Talbot-Caroline-
512 AM EDT Thu Aug 20 2026

This Hazardous Weather Outlook is for northeast Maryland.

.DAY ONE...Today and tonight.

Numerous thunderstorms are expected between about 2 PM and 8 PM. These
storms may contain damaging wind gusts and potentially a couple of
tornadoes over the Eastern Shore. Storms will be capable of producing
heavy rainfall, with rainfall rates of 2 to 4" per hour possible.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday.

The probability for widespread hazardous weather is low.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

Hoeflich

In the hours before

Local storm report, Aug 20, 5:48 PM EDT, 50 minutes before
Preliminary Local Storm Report
National Weather Service Mount Holly NJ
548 PM EDT Thu Aug 20 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0525 PM     Tstm Wnd Dmg     Glenmoore               40.09N 75.77W
08/20/2026                   Chester            PA   Public

            Trees and wires down across Creek Road with
            wires arcing. Time estimated from radar.

&&

PF
Local storm report, Aug 20, 6:04 PM EDT, 34 minutes before
Preliminary Local Storm Report
National Weather Service Mount Holly NJ
604 PM EDT Thu Aug 20 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0550 PM     Rain             1 SE Atlantic City Inte 39.44N 74.55W
08/20/2026  M1.98 Inch       Atlantic           NJ   Trained Spotter

            CoCoRaHS station reported 1.98 inches of
            rain over 2 hours.

&&

MJL
Local storm report, Aug 20, 6:18 PM EDT, 20 minutes before
Preliminary Local Storm Report
National Weather Service Mount Holly NJ
618 PM EDT Thu Aug 20 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0550 PM     Rain             3 SW Milmay             39.40N 74.89W
08/20/2026  M3.51 Inch       Cumberland         NJ   Trained Spotter

            CoCoRaHS station Estell Manor 4.0 WNW
            reported 3.51 inches of rainfall over 3
            hours.

&&

MJL
Local storm report, Aug 20, 6:20 PM EDT, 18 minutes before
Preliminary Local Storm Report
National Weather Service Mount Holly NJ
620 PM EDT Thu Aug 20 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0618 PM     Tornado          Dover                   39.16N 75.54W
08/20/2026                   Kent               DE   Trained Spotter

            Trained spotter reported a rain wrapped
            tornado on the ground, flying debris.

&&

MJL
Local storm report, Aug 20, 6:31 PM EDT, 7 minutes before
Preliminary Local Storm Report
National Weather Service Mount Holly NJ
631 PM EDT Thu Aug 20 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0615 PM     Flash Flood      Wilmington Manor        39.69N 75.59W
08/20/2026                   New Castle         DE   Public

            Road Flooding up to 5 inches deep occurring
            on East Basin Road near 624 East Basin Road.

&&

PF
Local storm report, Aug 20, 6:34 PM EDT, 4 minutes before
Preliminary Local Storm Report
National Weather Service Mount Holly NJ
634 PM EDT Thu Aug 20 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0530 PM     Flash Flood      1 NNE Cardiff           39.43N 74.58W
08/20/2026                   Atlantic           NJ   Public

            Several inches of water on AC Expressway
            near mile marker 8.9. One lane impassable.

&&

MJL

The office that day

Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 20, 2:04 PM EDTSpecial Marine WarningPHI86 min
Aug 20, 3:26 PM EDTSpecial Marine WarningPHI94 min
Aug 20, 4:38 PM EDTTornado WarningPHIAtlantic37 min
Aug 20, 4:41 PM EDTFlash Flood WarningPHIAtlantic, Cape May, Cumberland4 hr
Aug 20, 5:13 PM EDTSpecial Marine WarningPHI92 min
Aug 20, 5:14 PM EDTSpecial Marine WarningPHI91 min
Aug 20, 5:24 PM EDTFlash Flood WarningPHIAtlantic4 hr
Aug 20, 5:27 PM EDTSevere Thunderstorm Warning Considerable damage threatPHIGloucester, Salem48 min
Aug 20, 5:36 PM EDTSpecial Marine WarningPHI84 min
Aug 20, 5:39 PM EDTFlash Flood WarningPHICamden, Gloucester, Salem4 hr
Aug 20, 6:09 PM EDTSevere Thunderstorm WarningPHICumberland, Gloucester, Salem51 min
Aug 20, 6:13 PM EDTSevere Thunderstorm WarningPHIBurlington, Camden, Gloucester, Mercer, Salem47 min
Aug 20, 6:15 PM EDTSpecial Marine WarningPHI60 min
Aug 20, 6:26 PM EDTFlash Flood WarningPHIMercer4 hr
Aug 20, 6:30 PM EDTSpecial Marine WarningPHI90 min
Aug 20, 6:44 PM EDTSpecial Marine WarningPHI61 min
Aug 20, 7:01 PM EDTTornado WarningPHIAtlantic, Cape May, Cumberland29 min
Aug 20, 7:08 PM EDTTornado Warning Tornado observedPHICape May22 min
Aug 20, 7:10 PM EDTSevere Thunderstorm WarningPHIAtlantic, Cape May, Cumberland50 min
Aug 20, 7:37 PM EDTSpecial Marine WarningPHI2 hr
Aug 20, 7:43 PM EDTSpecial Marine WarningPHI2 hr

Nearby

Severe Thunderstorm Warnings in New Jersey, 2026Every severe thunderstorm warning in 2026

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.