Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2026

Severe Thunderstorm Warning 212, NWS Philadelphia/Mount Holly

July 21, 2026Chester County, Delaware County, Pennsylvania; New Castle County, Delaware; Gloucester County, Salem County, New Jersey

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 21, 2026, 4:43 PM EDT for Chester County, Delaware County, Pennsylvania; New Castle County, Delaware; Gloucester County, Salem County, New Jersey. It was in force for 47 min. 4 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
Jul 21, 2026, 4:43 PM EDT (20:43 UTC)
Expired
Jul 21, 2026, 5:30 PM EDT
In force
47 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

Counties New Castle County, DE, Gloucester County, NJ, Salem County, NJ, Chester County, PA, Delaware County, PA

The radar

The Philadelphia radar (KDIX), 105 km from the middle of the area, began a volume at 20:42 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
Jul 21, 5:02 PM EDTTSTM WND DMG2 Wsw Eastburn Heights, DETrees and wires down on Laurel Ave. Time estimated from radar.
Jul 21, 5:09 PM EDTTSTM WND DMG1 Nnw Nottingham Manor, DETree down on a house on Bridlebrook Ln.
Jul 21, 5:14 PM EDTTSTM WND DMG1 Wnw Nottingham Manor, DEDebris broke the window out on a house on Panorama Dr.
Jul 21, 5:15 PM EDTTSTM WND DMG2 Wsw Eastburn Heights, DEPoles and wires down at Capitol Trail and Polly Drummond Hill Rd.

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 4 storm reports to this severe thunderstorm warning; the first came 19 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
Jul 21, 2:06 PM EDTTornado WatchSPC7 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 8.7 hours before the alert went out and 180 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 2026-07-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 941 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Washington/Dulle, VA at 12:00Z on 2026-07-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 68 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
941 J/kg
Mixed-layer CIN
-113 J/kg
Mixed-layer LCL
772 m above ground
0-6 km bulk shear
35 kt
0-1 km storm-relative helicity
68 m²/s²
0-3 km storm-relative helicity
112 m²/s²
Significant tornado parameter
0.2
Supercell composite
0.9

Open this sounding in Storm Lab

The text

As transmitted.

763 
WUUS51 KPHI 212043
SVRPHI
DEC003-NJC015-033-PAC029-045-212130-
/O.NEW.KPHI.SV.W.0212.260721T2043Z-260721T2130Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
443 PM EDT Tue Jul 21 2026

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Northern New Castle County in northern Delaware...
  Northwestern Salem County in southern New Jersey...
  Northwestern Gloucester County in southern New Jersey...
  South central Chester County in southeastern Pennsylvania...
  Southern Delaware County in southeastern Pennsylvania...

* Until 530 PM EDT.

* At 443 PM EDT, a severe thunderstorm was located over Ashland, or 9
  miles northwest of Wilmington, moving east at 30 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

  IMPACT...Damage to roofs, siding, trees, and power lines is 
           possible.

* Locations impacted include...
  Wilmington, Newark, Chester, Pennsville, Yeadon, Carneys Point,
  Folcroft, Swarthmore, Elsmere, Paulsboro, Kennett Square, New
  Castle, Penns Grove, Oxford, Woodstown, Swedesboro, Newport, Arden,
  Darby Township, and Stanton.

This includes the following highways...
 New Jersey Turnpike between exits 1 and 2.
 Interstate 95 in Pennsylvania between mile markers 0 and 11.
 Interstate 95 in Delaware between mile markers 1 and 23.
 Interstate 295 in New Jersey between mile markers 0 and 17.
 Interstate 476 in Pennsylvania between mile markers 0 and 4.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 900 PM EDT for northern
Delaware...southern New Jersey...and southeastern Pennsylvania.

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

A Tornado Watch remains in effect until 900 PM EDT for northern
Delaware...southern New Jersey...and southeastern Pennsylvania.

&&

LAT...LON 3977 7603 3981 7577 3992 7574 3993 7525
      3990 7525 3989 7526 3987 7525 3961 7525
      3964 7579 3972 7579 3972 7603
TIME...MOT...LOC 2043Z 270DEG 28KT 3983 7565 

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

$$

AKL
1 follow-up statement
818 
WWUS51 KPHI 212113
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
513 PM EDT Tue Jul 21 2026

PAC029-212122-
/O.CAN.KPHI.SV.W.0212.000000T0000Z-260721T2130Z/
Chester PA-
513 PM EDT Tue Jul 21 2026

...THE SEVERE THUNDERSTORM WARNING FOR SOUTH CENTRAL CHESTER COUNTY
IS CANCELLED...

The severe thunderstorm which prompted the warning has moved out of 
the warned area. Therefore, the warning has been cancelled.

A Tornado Watch remains in effect until 900 PM EDT for northern
Delaware...southern New Jersey...and southeastern Pennsylvania.

LAT...LON 3978 7573 3988 7525 3961 7525 3965 7577
      3972 7578
TIME...MOT...LOC 2112Z 263DEG 29KT 3972 7568 

$$

DEC003-NJC015-033-PAC045-212130-
/O.CON.KPHI.SV.W.0212.000000T0000Z-260721T2130Z/
New Castle DE-Salem NJ-Gloucester NJ-Delaware PA-
513 PM EDT Tue Jul 21 2026

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 530 PM EDT
FOR NORTHERN NEW CASTLE...NORTHWESTERN SALEM...NORTHWESTERN
GLOUCESTER AND SOUTHEASTERN DELAWARE COUNTIES...

At 512 PM EDT, a severe thunderstorm was located over Pike Creek, or
near Newark, moving east at 35 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Damage to roofs, siding, trees, and power lines is 
         possible.

Locations impacted include...
Wilmington, Newark, Chester, Pennsville, Carneys Point, Elsmere,
Paulsboro, New Castle, Penns Grove, Woodstown, Swedesboro, Newport,
Arden, Stanton, North Star, Talleyville, Wilmington Manor, Pike
Creek, Beckett, and Greenville.

This includes the following highways...
 New Jersey Turnpike between exits 1 and 2.
 Interstate 95 in Pennsylvania between mile markers 0 and 5, and
between mile markers 11 and 12.
 Interstate 95 in Delaware between mile markers 3 and 23.
 Interstate 295 in New Jersey between mile markers 0 and 17.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 900 PM EDT for northern
Delaware...southern New Jersey...and southeastern Pennsylvania.

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

&&

LAT...LON 3978 7573 3988 7525 3961 7525 3965 7577
      3972 7578
TIME...MOT...LOC 2112Z 263DEG 29KT 3972 7568 

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

$$

AKL

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 Jul 21, 4:16 PM EDT, 27 minutes earlier. Its key messages:

  • 1. There continues to be an elevated risk for severe thunderstorms and flash flooding today and Wednesday, with the greater risk through this evening.
Area forecast discussion, Jul 21, 4:16 PM EDT, 27 minutes before
Area Forecast Discussion
National Weather Service Mount Holly NJ
416 PM EDT Tue Jul 21 2026

.WHAT HAS CHANGED...
A Tornado Watch has been issued until 9PM tonight.
A Severe Thunderstorm Watch has been issued until 10PM tonight.

&&

.KEY MESSAGES...
1. There continues to be an elevated risk for severe thunderstorms
and flash flooding today and Wednesday, with the greater risk
through this evening.

&&

.DISCUSSION...
KEY MESSAGE 1...There continues to be an elevated risk for severe
thunderstorms and flash flooding today and Wednesday, with the
greater risk through this evening.

A Tornado Watch has been issued until 9PM tonight for New
Jersey, eastern PA, and northern Delaware.

A Severe Thunderstorm Watch has been issued until 10PM tonight
for the central and southern Delmarva.

Severe thunderstorms continue to pop off across the region this
afternoon and are expected to become more widespread through the
evening. Several moving parts are coinciding to develop a
widespread severe and flash flooding threat. On the mesoscale,
an MCS that developed across the Ohio River Valley earlier this
morning has collided with a warm front that has draped across
the NJ/NY border. This MCS has already resulted in several
tornado warnings across northern NJ and into portions of
southern NY and northeast PA. This threat looks to persist for
at least the next few hours. On the synoptic scale, an upper-
level trough continues to provide strong mid to upper level flow
across the Mid Atlantic, resulting in widespread convective
development. In the near-term, the convection has begun to
concentrate itself along a pre-frontal trough across central and
eastern PA this afternoon. Storms have shown severe potential
cross this region and have also begun to congeal and train,
increasing the flash flood threat. Another round of storms may
pivot from central PA/MD border down into the Delmarva tonight
as well. Storm evolution has already become rather chaotic this
afternoon and is expected to become more disorderly through the
evening before the cold front arrives from the west and pushes
all the convection towards the coast by midnight or so. Any of
these storms have the potential to also produce rainfall rates
of 1-3 inches per hour at times. Overall rainfall amounts will
be a widespread 1-3 inches with locally higher amounts. Damaging
wind gusts, flash flooding, a few tornadoes, and hail are all
possible through tonight.

During the overnight hours, convection may persist mainly across
the southern Delmarva as the frontal boundary stalls across the
region. The flash flood guidance for this region is not as
sensitive to excessive rainfall, but will still bear monitoring
through the early morning hours.

On Wednesday, the cold front will sag farther south and east and
depending on how quickly this clears our area there will be some
showers and thunderstorms, especially as additional shortwaves move
through the flow within the upper-level trough overhead. This looks
to be more concentrated across southern New Jersey to Delmarva but
could extend into the I-95 corridor for a time. There is some severe
weather risk mainly near and south/east of the I-95 corridor with
locally damaging wind gusts the main threat. The greater instability
and shear looks to reside across Delmarva on southward, where a
little higher severe thunderstorm risk is indicated. Some locally
excessive rainfall is possible with some local flash flood risk,
however this looks to be less compared to today given the shift
farther south and more into the coastal plain. Once the front moves
away by later Wednesday, it turns drier for Thursday/Friday and
right into the weekend.

&&

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

Through 04Z...Prevailing VFR ceilings. However, expecting
increasing coverage of showers and thunderstorms after 18z from
west to east with MVFR/IFR conditions at times. The most
widespread coverage is expected between 20 and 02Z from West to
East. Locally strong and variable winds probable with stronger
thunderstorms. Otherwise, southwest winds 10-15 knots. Moderate
confidence.

After 04Z through 12Z...Once storms clear out, prevailing MVFR
ceilings likely, localized IFR conditions possible. South to
southwest winds 10 knots or less. Low confidence.

Wednesday...Once morning clouds clear by 15Z, should have
prevailing VFR conditions. However, temporary MVFR or even IFR
conditions will be possible with showers and storms. The highest
risk of showers and storms is at KACY, but it is possible the
storms will be south of all TAF sites. Southwest winds around 10
KT.

Outlook...

Thursday through Saturday...VFR.

&&

.MARINE...
Small Craft Advisory conditions for all coastal waters through
Wednesday evening. SCA conditions do subside though overnight
on Delaware Bay. Gusty thunderstorms probable mainly this
evening and into tonight.

Outlook...

Wednesday...Small Craft Advisory remains in effect for the ocean
zones.

Thursday through Saturday...The conditions are anticipated to be
below Small Craft Advisory criteria.

Rip Currents...

For the rest of today, southerly winds of 15-25 mph with either a
shore parallel or slight onshore flow expected depending on
location. Breaking waves of 2-4 feet will result in more energy
within the surf zone. As a result, maintained a MODERATE risk for
the development of dangerous rip currents at all beaches.

For Wednesday, winds turn more southwesterly but still 10-20 mph.
However, breaking wave heights are expected to increase, with
breaking waves in the surf zone as high as 5 feet possible. Still a
7 second period though which will mitigate the rip current threat
some. However, will continue with a MODERATE risk for the
development of dangerous rip currents at all beaches.

For Thursday, winds come around to the northeast and will generally
be 15 to 20 mph. Breaking waves are expected to be around 2-4 feet
with a 7 second period. With the onshore component of the wind and
multiple swell groups expected, expecting a MODERATE risk for the
development of dangerous rip currents at all beaches.

For specific beach forecasts, visit weather.gov/beach/phi

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...Flood Watch until 2 AM EDT Wednesday for PAZ070-071-101>106.
NJ...Flood Watch until 2 AM EDT Wednesday for NJZ008>010-012>015-
     017>019.
DE...Flood Watch until 2 AM EDT Wednesday for DEZ001.
MD...None.
MARINE...Small Craft Advisory until 6 AM EDT Wednesday for ANZ430-431.
     Small Craft Advisory until 2 AM EDT Thursday for ANZ450>455.

&&

DISCUSSION...Gorse/MJL
AVIATION...Gorse/Johnson
MARINE...Gorse/Hoeflich/MJL
Hazardous weather outlook, Jul 21, 4:29 AM EDT, 12 hours 14 minutes before
Hazardous Weather Outlook
National Weather Service Mount Holly NJ
429 AM EDT Tue Jul 21 2026

MDZ012-015-019-020-220900-
Kent MD-Queen Annes-Talbot-Caroline-
429 AM EDT Tue Jul 21 2026

This Hazardous Weather Outlook is for northeast Maryland.

.DAY ONE...Today and tonight.

Severe thunderstorms with damaging winds and hail are possible this
afternoon and evening. Localized flash flooding is possible this
afternoon and tonight.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday.

Some severe thunderstorms with damaging winds are possible Wednesday.
Localized flash flooding is possible on Wednesday.

.SPOTTER INFORMATION STATEMENT...

Weather spotters are encouraged to report significant weather
conditions according to standard operating procedures.

In the hours before

Local storm report, Jul 21, 12:16 PM EDT, 4 hours 27 minutes before
Preliminary Local Storm Report
National Weather Service Mount Holly NJ
1216 PM EDT Tue Jul 21 2026

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

1130 AM     Marine Tstm Wind 19 E Fenwick Island     38.46N 74.69W
07/21/2026  M47 MPH          ANZ485             DE   Buoy

            NDBC Buoy 44009 - DELAWARE BAY 26 NM
            Southeast of Cape May NJ gusted to 40.8 kt.

&&

DeSilva
Local storm report, Jul 21, 2:42 PM EDT, 2 hours 1 minute before
Preliminary Local Storm Report
National Weather Service Mount Holly NJ
242 PM EDT Tue Jul 21 2026

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

0210 PM     Tornado          1 W Stanhope            40.90N 74.72W
07/21/2026                   Morris             NJ   Trained Spotter

            Trained spotter witnessed tornado touching
            down at the intersection of Interstate 80
            and US Route 206. Trees and debris on road.

&&

PF
Local storm report, Jul 21, 3:20 PM EDT, 1 hour 23 minutes before
Preliminary Local Storm Report
National Weather Service Mount Holly NJ
320 PM EDT Tue Jul 21 2026

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

0243 PM     Tornado          1 N Troy Hills          40.86N 74.39W
07/21/2026                   Morris             NJ   Trained Spotter

            Video sent in of a tornado on the ground
            sent from a driving range in Parsippany.
            Time estimated from radar.

&&

Hoeflich
Local storm report, Jul 21, 3:24 PM EDT, 1 hour 19 minutes before
Preliminary Local Storm Report
National Weather Service Mount Holly NJ
324 PM EDT Tue Jul 21 2026

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

0320 PM     Flash Flood      2 NNE Dover             40.91N 74.55W
07/21/2026                   Morris             NJ   Dept of Highways

            Exit 35 ramp closed on I-80 due to high
            water and flooded roadways.

&&

Hoeflich

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 21, 2:18 PM EDTSevere Thunderstorm WarningPHIBerks, Lehigh42 min
Jul 21, 2:57 PM EDTSevere Thunderstorm WarningPHIBucks, Lehigh, Northampton37 min
Jul 21, 3:37 PM EDTSevere Thunderstorm WarningPHIChester, Delaware53 min
Jul 21, 3:47 PM EDTSevere Thunderstorm WarningPHICarbon, Monroe43 min
Jul 21, 3:58 PM EDTSevere Thunderstorm WarningPHIChester, Delaware47 min
Jul 21, 4:23 PM EDTSevere Thunderstorm WarningPHIChester, Delaware, Montgomery, Philadelphia52 min
Jul 21, 4:31 PM EDTFlash Flood WarningPHIChester, Delaware96 min
Jul 21, 4:38 PM EDTFlash Flood Warning Considerable damage threatPHIChester, Delaware, Montgomery, Philadelphia4 hr
Jul 21, 5:30 PM EDTSevere Thunderstorm WarningPHIDelaware45 min
Jul 21, 5:06 PM EDTSevere Thunderstorm WarningPHIKent39 min
Jul 21, 5:42 PM EDTSevere Thunderstorm Warning Considerable damage threatPHIKent48 min
Jul 21, 6:00 PM EDTSevere Thunderstorm WarningPHIKent, New Castle45 min
Jul 21, 6:53 PM EDTFlash Flood WarningPHIKent, New Castle3 hr
Jul 21, 8:49 AM EDTFlash Flood WarningPHISussex, Warren2 hr
Jul 21, 11:01 AM EDTSpecial Marine WarningPHI59 min
Jul 21, 11:14 AM EDTSpecial Marine WarningPHI46 min
Jul 21, 12:07 PM EDTSpecial Marine WarningPHI53 min
Jul 21, 1:52 PM EDTSevere Thunderstorm WarningPHIMorris, Sussex, Warren53 min
Jul 21, 2:00 PM EDTTornado WarningPHIMorris30 min
Jul 21, 2:25 PM EDTTornado WarningPHIMorris50 min
Jul 21, 2:49 PM EDTFlash Flood WarningPHIMorris3 hr
Jul 21, 2:57 PM EDTTornado WarningPHIMorris, Somerset48 min
Jul 21, 3:13 PM EDTFlash Flood WarningPHIMorris, Somerset3 hr
Jul 21, 4:06 PM EDTSpecial Marine WarningPHI54 min
Jul 21, 4:46 PM EDTSpecial Marine WarningPHI89 min
Jul 21, 4:50 PM EDTSevere Thunderstorm WarningPHIMercer, Middlesex, Monmouth, Somerset55 min
Jul 21, 5:14 PM EDTSevere Thunderstorm WarningPHIBurlington, Camden46 min
Jul 21, 5:30 PM EDTSpecial Marine WarningPHI2 hr
Jul 21, 5:43 PM EDTSpecial Marine WarningPHI2 hr
Jul 21, 5:49 PM EDTTornado WarningPHICape May26 min
Jul 21, 6:06 PM EDTSevere Thunderstorm WarningPHIBurlington, Ocean39 min
Jul 21, 6:07 PM EDTSpecial Marine WarningPHI53 min
Jul 21, 6:09 PM EDTTornado WarningPHICape May36 min
Jul 21, 6:18 PM EDTSpecial Marine WarningPHI57 min
Jul 21, 6:34 PM EDTSevere Thunderstorm WarningPHIAtlantic, Burlington, Ocean41 min
Jul 21, 6:41 PM EDTSpecial Marine WarningPHI94 min
Jul 21, 6:50 PM EDTSpecial Marine WarningPHI85 min
Jul 21, 7:06 PM EDTTornado WarningPHIOcean12 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2026Severe Thunderstorm Warnings in New Jersey, 2026Severe Thunderstorm Warnings in Delaware, 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.