Alert archive / Delaware / Flash Flood Warnings in 2026

Flash Flood Warning 133, NWS Philadelphia/Mount Holly

August 27, 2026New Castle County, Delaware; Salem County, New Jersey

NWS Philadelphia/Mount Holly issued this flash flood warning at Aug 27, 2026, 1:50 PM EDT for New Castle County, Delaware; Salem County, New Jersey. It was in force for 4 hr. 1 report 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 27, 2026, 1:50 PM EDT (17:50 UTC)
Expired
Aug 27, 2026, 5:45 PM EDT
In force
4 hr
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Flood severity
None

Counties New Castle County, DE, Salem County, NJ

The radar

The Dover AFB radar (KDOX), 94 km from the middle of the area, began a volume at 17:52 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 27, 4:25 PM EDTRAIN 1.78Pennsville, NJMesonet station FW8127 Pennsville.

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, 5.8 hours before the alert went out and 179 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 2026-08-27Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 728 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 2026-08-27The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 145 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
728 J/kg
Mixed-layer CIN
-107 J/kg
Mixed-layer LCL
980 m above ground
0-6 km bulk shear
33 kt
0-1 km storm-relative helicity
145 m²/s²
0-3 km storm-relative helicity
120 m²/s²
Significant tornado parameter
0.2
Supercell composite
2.7

Open this sounding in Storm Lab

The text

As transmitted.

128 
WGUS51 KPHI 271750
FFWPHI
DEC003-NJC033-272145-
/O.NEW.KPHI.FF.W.0133.260827T1750Z-260827T2145Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
Issued by National Weather Service New York NY
150 PM EDT Thu Aug 27 2026

The National Weather Service in Mount Holly has issued a

* Flash Flood Warning for...
  Northeastern New Castle County in northern Delaware...
  Northwestern Salem County in southern New Jersey...

* Until 545 PM EDT.

* At 150 PM EDT, Doppler radar indicated thunderstorms producing
  heavy rain across the warned area. Between 2 and 3 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...Flash flooding caused by thunderstorms.

  SOURCE...Radar indicated.

  IMPACT...Flash flooding of small creeks and streams, urban areas,
           highways, streets and underpasses as well as other poor
           drainage and low-lying areas.

* Some locations that will experience flash flooding include...
  Wilmington, Pennsville, Carneys Point, Elsmere, New Castle, Penns
  Grove, Woodstown, Newport, Delaware Memorial Bridge, Wilmington
  Manor, Bear and Edgemoor.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3959 7561 3958 7567 3975 7563 3973 7556
      3978 7543 3978 7541 3979 7541 3969 7539
      3966 7529 3960 7559 3961 7558 3963 7558
      3961 7560 3959 7560

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

$$

PHI
2 follow-up statements
578 
WGUS71 KPHI 272026
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
Issued by National Weather Service New York NY
426 PM EDT Thu Aug 27 2026

DEC003-NJC033-272145-
/O.CON.KPHI.FF.W.0133.000000T0000Z-260827T2145Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
New Castle DE-Salem NJ-
426 PM EDT Thu Aug 27 2026

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 545 PM EDT THIS
AFTERNOON FOR NORTHEASTERN NEW CASTLE AND NORTHWESTERN SALEM
COUNTIES...

At 426 PM EDT, Doppler radar indicated thunderstorms producing heavy
rain across the warned area. Between 2 and 3 inches of rain have
fallen. The expected rainfall rate is 0.5 inches in 1 hour.
Additional rainfall amounts up to 0.5 inches are possible in the
warned area. Flash flooding is ongoing or expected to begin shortly.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Radar indicated.

IMPACT...Flash flooding of small creeks and streams, urban areas,
         highways, streets and underpasses as well as other poor
         drainage and low-lying areas.

Some locations that will experience flash flooding include...
  Wilmington, Pennsville, Carneys Point, Elsmere, New Castle, Penns
  Grove, Woodstown, Newport, Delaware Memorial Bridge, Wilmington
  Manor, Bear and Edgemoor.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3959 7561 3958 7567 3975 7563 3973 7556
      3978 7543 3978 7541 3979 7541 3969 7539
      3966 7529 3960 7559 3961 7558 3963 7558
      3961 7560 3959 7560

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL RATE...0.5 INCHES IN 1 HOUR

$$

PHI
172 
WGUS71 KPHI 272136
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
Issued by National Weather Service New York NY
536 PM EDT Thu Aug 27 2026

DEC003-NJC033-272146-
/O.EXP.KPHI.FF.W.0133.000000T0000Z-260827T2145Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
New Castle DE-Salem NJ-
536 PM EDT Thu Aug 27 2026

...FLASH FLOOD WARNING WILL EXPIRE AT 545 PM EDT THIS AFTERNOON FOR
NORTHEASTERN NEW CASTLE AND NORTHWESTERN SALEM COUNTIES...

The heavy rain has ended. Flooding is no longer expected to pose a
threat. Please continue to heed remaining road closures.

A Flood Watch remains in effect until 400 AM EDT Friday for portions
of northern Delaware, New Jersey, and Pennsylvania.

&&

LAT...LON 3959 7561 3958 7567 3975 7563 3973 7556
      3978 7543 3978 7541 3979 7541 3969 7539
      3966 7529 3960 7559 3961 7558 3963 7558
      3961 7560 3959 7560

$$

PHI

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 27, 11:38 AM EDTFlash Flood WarningPHINew Castle4 hr
Aug 27, 1:32 PM EDTSevere Thunderstorm WarningPHINew Castle43 min
Aug 27, 3:26 PM EDTAreal Flood WarningPHINew Castle5 hr
Aug 27, 12:26 PM EDTSevere Thunderstorm WarningPHICamden, Gloucester49 min
Aug 27, 12:41 PM EDTFlash Flood WarningPHICamden, Gloucester, Salem5 hr
Aug 27, 1:06 PM EDTSevere Thunderstorm WarningPHIMiddlesex24 min
Aug 27, 1:07 PM EDTFlash Flood WarningPHIMiddlesex, Somerset4 hr
Aug 27, 1:15 PM EDTSevere Thunderstorm WarningPHIAtlantic, Burlington, Camden, Gloucester45 min
Aug 27, 1:17 PM EDTFlash Flood WarningPHIMercer, Somerset7 hr
Aug 27, 1:20 PM EDTSevere Thunderstorm WarningPHIMiddlesex, Monmouth40 min
Aug 27, 1:26 PM EDTSevere Thunderstorm WarningPHIMiddlesex, Monmouth49 min
Aug 27, 1:34 PM EDTSpecial Marine WarningPHI21 min
Aug 27, 1:57 PM EDTTornado WarningPHISalem11 min
Aug 27, 2:02 PM EDTSevere Thunderstorm WarningPHIMonmouth28 min
Aug 27, 2:13 PM EDTSevere Thunderstorm WarningPHIMonmouth47 min
Aug 27, 2:16 PM EDTSevere Thunderstorm WarningPHICamden, Gloucester, Salem44 min
Aug 27, 2:18 PM EDTFlash Flood WarningPHIMiddlesex, Monmouth4 hr
Aug 27, 2:20 PM EDTSpecial Marine WarningPHI40 min
Aug 27, 2:31 PM EDTSevere Thunderstorm WarningPHIBurlington, Ocean44 min
Aug 27, 2:38 PM EDTFlash Flood WarningPHICamden4 hr
Aug 27, 2:58 PM EDTSevere Thunderstorm WarningPHIMonmouth30 min
Aug 27, 3:00 PM EDTSpecial Marine WarningPHI60 min
Aug 27, 3:04 PM EDTSevere Thunderstorm WarningPHIAtlantic, Burlington, Camden41 min
Aug 27, 3:43 PM EDTFlash Flood WarningPHICamden3 hr
Aug 27, 4:52 PM EDTFlash Flood WarningPHIWarren3 hr
Aug 27, 4:59 PM EDTAreal Flood WarningPHIMiddlesex, Somerset4 hr
Aug 27, 5:44 PM EDTAreal Flood WarningPHICamden, Gloucester5 hr
Aug 27, 6:17 PM EDTAreal Flood WarningPHIMiddlesex, Monmouth4 hr
Aug 27, 7:00 PM EDTFlash Flood WarningPHIBurlington, Camden3 hr
Aug 27, 7:26 PM EDTSpecial Marine WarningPHI32 min

Nearby

Flash Flood Warnings in Delaware, 2026Flash Flood Warnings in New Jersey, 2026Every 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.