Alert archive / Pennsylvania / Flash Flood Warnings in 2026

Flash Flood Warning 60, NWS Philadelphia/Mount Holly

July 21, 20264 counties in Pennsylvania; New Castle County, Delaware; 4 counties in New Jersey

NWS Philadelphia/Mount Holly issued this flash flood warning at Jul 21, 2026, 4:38 PM EDT for 4 counties in Pennsylvania; New Castle County, Delaware; 4 counties in New Jersey. It was in force for 4 hr. 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, 4:38 PM EDT (20:38 UTC)
Expired: Jul 21, 2026, 8:45 PM EDT
In force: 4 hr
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Damage threat: Considerable
Flood severity: None

Counties New Castle County, DE, Burlington County, NJ, Camden County, NJ, Gloucester County, NJ, Salem County, NJ, Chester County, PA, Delaware County, PA, Montgomery County, PA, Philadelphia County, PA

The radar

The Philadelphia radar (KDIX), 100 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

Time	Report	Where	Remark
Jul 21, 5:24 PM EDT	FLASH FLOOD	1 Wsw Penn Rose, DE	Water rescues on N Market St. Water up to the door of businesses with subjects stranded.
Jul 21, 5:35 PM EDT	FLASH FLOOD	1 Se New Castle County, DE	Vehicles stuck in flood waters along DuPont Highway.
Jul 21, 5:36 PM EDT	FLASH FLOOD	Rose Hill Gardens, DE	Vehicles stranded in flood waters on New Castle Ave.
Jul 21, 5:36 PM EDT	FLASH FLOOD	White Clay Creek, DE	Water rescues reported on Paper Mill and Creek View Rd.

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

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 8.6 hours before the alert went out and 183 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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.

185 
WGUS51 KPHI 212038
FFWPHI
DEC003-NJC005-007-015-033-PAC029-045-091-101-220045-
/O.NEW.KPHI.FF.W.0060.260721T2038Z-260722T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
438 PM EDT Tue Jul 21 2026

The National Weather Service in Mount Holly has issued a

* Flash Flood Warning for...
  Northern New Castle County in northern Delaware...
  Northwestern Burlington County in southern New Jersey...
  Northwestern Camden County in southern New Jersey...
  Northwestern Gloucester County in southern New Jersey...
  Northwestern Salem County in southern New Jersey...
  Southeastern Chester County in southeastern Pennsylvania...
  Delaware County in southeastern Pennsylvania...
  Southern Montgomery County in southeastern Pennsylvania...
  Philadelphia County in southeastern Pennsylvania...

* Until 845 PM EDT.

* At 438 PM EDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Up to 0.5 inches of rain have 
  fallen. The expected rainfall rate is 1 to 2 inches in 1 hour. 
  Additional rainfall amounts of 1 to 2 inches are possible in the 
  warned area. Flash flooding is ongoing or expected to begin 
  shortly.

  HAZARD...Life threatening flash flooding caused by
           thunderstorms.

  SOURCE...Radar.

  IMPACT...Life threatening flash flooding of creeks and streams,
           urban areas, highways, streets, and underpasses.

* Some locations that may experience flash flooding include...
  Philadelphia, Camden, Wilmington, Newark, Gloucester City, 
  Chester, Deptford, West Deptford, Pennsville, Bellmawr, Yeadon and 
  Westtown.

This includes the following highways...
	Interstate 295 in New Jersey between mile markers 0 and 27.
	Interstate 476 in Pennsylvania between mile markers 0 and 14.
	New Jersey Turnpike between exits 1 and 2.
	Interstate 76 in Pennsylvania between mile markers 336 and 351.
	Interstate 95 in Pennsylvania between mile markers 0 and 32.
	Interstate 676 in Pennsylvania between mile markers 0 and 1.
	Interstate 676 in New Jersey between mile markers 0 and 4.
	Interstate 76 in New Jersey between mile markers 0 and 3.
	Interstate 95 in Delaware between mile markers 0 and 23.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around...don't drown when encountering flooded roads. Most 
flood deaths occur in vehicles.

&&

LAT...LON 3972 7595 3991 7555 4005 7556 4005 7488
      3982 7516 3960 7553 3959 7578 3972 7579

FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
EXPECTED RAINFALL RATE...1-2 INCHES IN 1 HOUR

$$

Kruzdlo

3 follow-up statements

894 
WGUS71 KPHI 212130
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
530 PM EDT Tue Jul 21 2026

DEC003-NJC005-007-015-033-PAC029-045-091-101-220045-
/O.CON.KPHI.FF.W.0060.000000T0000Z-260722T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
New Castle DE-Burlington NJ-Camden NJ-Gloucester NJ-Salem NJ-
Chester PA-Delaware PA-Montgomery PA-Philadelphia PA-
530 PM EDT Tue Jul 21 2026

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 845 PM EDT THIS 
EVENING FOR NORTHERN NEW CASTLE, NORTHWESTERN BURLINGTON, 
NORTHWESTERN CAMDEN, NORTHWESTERN GLOUCESTER, NORTHWESTERN SALEM, 
SOUTHEASTERN CHESTER, DELAWARE, SOUTHERN MONTGOMERY AND PHILADELPHIA 
COUNTIES...

At 530 PM EDT, the Emergency Manager in New Castle Castle, Delaware 
reported water rescues were ongoing on North Market Street in 
Wilmington. Water was up to the doors of businesses with subjects 
stuck in place.

HAZARD...Life threatening flash flooding caused by thunderstorms.

SOURCE...Radar.

IMPACT...Life threatening flash flooding of creeks and streams,
         urban areas, highways, streets, and underpasses.

Some locations that may experience flash flooding include...
  Philadelphia, Camden, Wilmington, Newark, Gloucester City, 
  Chester, Deptford, West Deptford, Pennsville, Bellmawr, Yeadon and 
  Westtown.

This includes the following highways...
	Interstate 295 in New Jersey between mile markers 0 and 27.
	Interstate 476 in Pennsylvania between mile markers 0 and 14.
	New Jersey Turnpike between exits 1 and 2.
	Interstate 76 in Pennsylvania between mile markers 336 and 351.
	Interstate 95 in Pennsylvania between mile markers 0 and 32.
	Interstate 676 in Pennsylvania between mile markers 0 and 1.
	Interstate 676 in New Jersey between mile markers 0 and 4.
	Interstate 76 in New Jersey between mile markers 0 and 3.
	Interstate 95 in Delaware between mile markers 1 and 23.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around...don't drown when encountering flooded roads. Most 
flood deaths occur in vehicles.

&&

LAT...LON 3972 7595 3991 7555 4005 7556 4005 7488
      3982 7516 3960 7553 3959 7578 3972 7579

FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE

$$

Kruzdlo

621 
WGUS71 KPHI 212205
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
605 PM EDT Tue Jul 21 2026

NJC005-007-015-033-PAC029-045-091-101-212215-
/O.CAN.KPHI.FF.W.0060.000000T0000Z-260722T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Burlington NJ-Camden NJ-Gloucester NJ-Salem NJ-Chester PA-
Delaware PA-Montgomery PA-Philadelphia PA-
605 PM EDT Tue Jul 21 2026

...FLASH FLOOD WARNING IS CANCELLED FOR NORTHWESTERN BURLINGTON, 
NORTHWESTERN CAMDEN, NORTHWESTERN GLOUCESTER, NORTHWESTERN SALEM, 
SOUTHEASTERN CHESTER, DELAWARE, SOUTHERN MONTGOMERY AND PHILADELPHIA 
COUNTIES...

The heavy rain has ended. Flooding is no longer expected to pose a 
threat.

A Flood Watch remains in effect until 200 AM EDT Wednesday for 
portions of northern Delaware, New Jersey, and southeast 
Pennsylvania.

&&

LAT...LON 3981 7569 3983 7562 3984 7555 3980 7541
      3976 7546 3971 7548 3970 7551 3965 7548
      3965 7546 3964 7546 3963 7556 3961 7554
      3959 7578 3972 7579

$$

DEC003-220045-
/O.CON.KPHI.FF.W.0060.000000T0000Z-260722T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
New Castle DE-
605 PM EDT Tue Jul 21 2026

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 845 PM EDT THIS 
EVENING FOR NORTHERN NEW CASTLE COUNTY...

At 605 PM EDT, New Castle County Emergency Managers reported 
flooding in Newark and Wilmington. Vehicles were stranded and water 
rescues were ongoing.

HAZARD...Life threatening flash flooding caused by thunderstorms.

SOURCE...Radar.

IMPACT...Life threatening flash flooding of creeks and streams,
         urban areas, highways, streets, and underpasses.

Some locations that may experience flash flooding include...
  Wilmington, Newark, Pennsville, Carneys Point, Elsmere, New 
  Castle, Penns Grove, Newport, Arden, Stanton, Wilmington Manor and 
  Greenville.

This includes Interstate 95 in Delaware between mile markers 1 and 
23.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around...don't drown when encountering flooded roads. Most 
flood deaths occur in vehicles.

&&

LAT...LON 3981 7569 3983 7562 3984 7555 3980 7541
      3976 7546 3971 7548 3970 7551 3965 7548
      3965 7546 3964 7546 3963 7556 3961 7554
      3959 7578 3972 7579

FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE

$$

Kruzdlo

752 
WGUS71 KPHI 220036
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
836 PM EDT Tue Jul 21 2026

DEC003-220046-
/O.EXP.KPHI.FF.W.0060.000000T0000Z-260722T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
New Castle DE-
836 PM EDT Tue Jul 21 2026

...FLASH FLOOD WARNING WILL EXPIRE AT 845 PM EDT THIS EVENING FOR 
NORTHERN NEW CASTLE COUNTY...

Flood waters have receded. Flooding is no longer expected to pose a 
threat. Please continue to heed remaining road closures.

A Flood Watch remains in effect until 200 AM EDT for portions of 
northern Delaware, New Jersey, and southeast Pennsylvania.

&&

LAT...LON 3981 7569 3983 7562 3984 7555 3980 7541
      3976 7546 3971 7548 3970 7551 3965 7548
      3965 7546 3964 7546 3963 7556 3961 7554
      3959 7578 3972 7579

$$

Hoeflich

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 21, 2:18 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Lehigh	42 min
Jul 21, 2:57 PM EDT	Severe Thunderstorm Warning	PHI	Bucks, Lehigh, Northampton	37 min
Jul 21, 3:37 PM EDT	Severe Thunderstorm Warning	PHI	Chester, Delaware	53 min
Jul 21, 3:47 PM EDT	Severe Thunderstorm Warning	PHI	Carbon, Monroe	43 min
Jul 21, 3:58 PM EDT	Severe Thunderstorm Warning	PHI	Chester, Delaware	47 min
Jul 21, 4:23 PM EDT	Severe Thunderstorm Warning	PHI	Chester, Delaware, Montgomery, Philadelphia	52 min
Jul 21, 4:31 PM EDT	Flash Flood Warning	PHI	Chester, Delaware	96 min
Jul 21, 4:43 PM EDT	Severe Thunderstorm Warning	PHI	Chester, Delaware	47 min
Jul 21, 5:30 PM EDT	Severe Thunderstorm Warning	PHI	Delaware	45 min
Jul 21, 5:06 PM EDT	Severe Thunderstorm Warning	PHI	Kent	39 min
Jul 21, 5:42 PM EDT	Severe Thunderstorm Warning Considerable damage threat	PHI	Kent	48 min
Jul 21, 6:00 PM EDT	Severe Thunderstorm Warning	PHI	Kent, New Castle	45 min
Jul 21, 6:53 PM EDT	Flash Flood Warning	PHI	Kent, New Castle	3 hr
Jul 21, 8:49 AM EDT	Flash Flood Warning	PHI	Sussex, Warren	2 hr
Jul 21, 11:01 AM EDT	Special Marine Warning	PHI		59 min
Jul 21, 11:14 AM EDT	Special Marine Warning	PHI		46 min
Jul 21, 12:07 PM EDT	Special Marine Warning	PHI		53 min
Jul 21, 1:52 PM EDT	Severe Thunderstorm Warning	PHI	Morris, Sussex, Warren	53 min
Jul 21, 2:00 PM EDT	Tornado Warning	PHI	Morris	30 min
Jul 21, 2:25 PM EDT	Tornado Warning	PHI	Morris	50 min
Jul 21, 2:49 PM EDT	Flash Flood Warning	PHI	Morris	3 hr
Jul 21, 2:57 PM EDT	Tornado Warning	PHI	Morris, Somerset	48 min
Jul 21, 3:13 PM EDT	Flash Flood Warning	PHI	Morris, Somerset	3 hr
Jul 21, 4:06 PM EDT	Special Marine Warning	PHI		54 min
Jul 21, 4:46 PM EDT	Special Marine Warning	PHI		89 min
Jul 21, 4:50 PM EDT	Severe Thunderstorm Warning	PHI	Mercer, Middlesex, Monmouth, Somerset	55 min
Jul 21, 5:14 PM EDT	Severe Thunderstorm Warning	PHI	Burlington, Camden	46 min
Jul 21, 5:30 PM EDT	Special Marine Warning	PHI		2 hr
Jul 21, 5:43 PM EDT	Special Marine Warning	PHI		2 hr
Jul 21, 5:49 PM EDT	Tornado Warning	PHI	Cape May	26 min
Jul 21, 6:06 PM EDT	Severe Thunderstorm Warning	PHI	Burlington, Ocean	39 min
Jul 21, 6:07 PM EDT	Special Marine Warning	PHI		53 min
Jul 21, 6:09 PM EDT	Tornado Warning	PHI	Cape May	36 min
Jul 21, 6:18 PM EDT	Special Marine Warning	PHI		57 min
Jul 21, 6:34 PM EDT	Severe Thunderstorm Warning	PHI	Atlantic, Burlington, Ocean	41 min
Jul 21, 6:41 PM EDT	Special Marine Warning	PHI		94 min
Jul 21, 6:50 PM EDT	Special Marine Warning	PHI		85 min
Jul 21, 7:06 PM EDT	Tornado Warning	PHI	Ocean	12 min

Nearby

Flash Flood Warnings in Pennsylvania, 2026 Flash Flood Warnings in New Jersey, 2026 Flash Flood Warnings in Delaware, 2026 Every flash flood 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.