Alert archive / Pennsylvania / Flash Flood Warnings in 2026

Flash Flood Warning 2, NWS Philadelphia/Mount Holly

June 14, 2026Chester County, Pennsylvania

NWS Philadelphia/Mount Holly issued this flash flood warning at Jun 14, 2026, 9:50 PM EDT for Chester County, Pennsylvania. It was in force for 3 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Jun 14, 2026, 9:50 PM EDT (01:50 UTC)
Expired
Jun 15, 2026, 12:40 AM EDT
In force
3 hr
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Flood severity
None

County Chester County, PA

The radar

The Dover AFB radar (KDOX), 123 km from the middle of the area, began a volume at 01:50 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.

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 00:00Z, 1.8 hours before the alert went out and 159 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 00:00Z on 2026-06-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 916 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 00:00Z on 2026-06-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 115 square meters per square second.19395878Sfc1 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
916 J/kg
Mixed-layer CIN
-14 J/kg
Mixed-layer LCL
1620 m above ground
0-6 km bulk shear
48 kt
0-1 km storm-relative helicity
115 m²/s²
0-3 km storm-relative helicity
225 m²/s²
Significant tornado parameter
0.2
Supercell composite
6.4

Open this sounding in Storm Lab

The text

As transmitted.

185 
WGUS51 KPHI 150150
FFWPHI
PAC029-150600-
/O.NEW.KPHI.FF.W.0002.260615T0150Z-260615T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
950 PM EDT Sun Jun 14 2026

The National Weather Service in Mount Holly has issued a

* Flash Flood Warning for...
  Southwestern Chester County in southeastern Pennsylvania...

* Until 200 AM EDT.

* At 950 PM EDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 1 and 1.5 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...Flash flooding caused by thunderstorms.

  SOURCE...Radar.

  IMPACT...Flooding of small creeks and streams, urban areas,
           highways, streets, and underpasses as well as other
           drainage and low lying areas.

* Some locations that may experience flash flooding include...
  Coatesville, Downingtown, Kennett Square, Oxford, Parkesburg, West 
  Grove, Honey Brook, Cochranville, Homeville, Landenberg, 
  Kemblesville and Marshallton.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3973 7579 3972 7612 3974 7612 3973 7609
      3975 7610 3976 7606 3983 7604 3983 7602
      3985 7602 3985 7601 3987 7600 3987 7599
      3993 7600 3993 7598 3995 7599 4004 7594
      4010 7594 4005 7567 3982 7569

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

$$

RCM
2 follow-up statements
565 
WGUS71 KPHI 150252
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
1052 PM EDT Sun Jun 14 2026

PAC029-150600-
/O.CON.KPHI.FF.W.0002.000000T0000Z-260615T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Chester PA-
1052 PM EDT Sun Jun 14 2026

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 2 AM EDT MONDAY FOR 
SOUTHWESTERN CHESTER COUNTY...

At 1052 PM EDT, local law enforcement reported 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 already occurring.

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

SOURCE...Law enforcement reported.

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

Some locations that may experience flash flooding include...
  Coatesville, Downingtown, Kennett Square, Oxford, Parkesburg, West 
  Grove, Honey Brook, Cochranville, Homeville, Landenberg, 
  Kemblesville and Marshallton.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3973 7579 3972 7612 3974 7612 3973 7609
      3975 7610 3976 7606 3983 7604 3983 7602
      3985 7602 3985 7601 3987 7600 3987 7599
      3993 7600 3993 7598 3995 7599 4004 7594
      4010 7594 4005 7567 3982 7569

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

$$

RCM
307 
WGUS71 KPHI 150440
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
1240 AM EDT Mon Jun 15 2026

PAC029-150450-
/O.CAN.KPHI.FF.W.0002.000000T0000Z-260615T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Chester PA-
1240 AM EDT Mon Jun 15 2026

...FLASH FLOOD WARNING IS CANCELLED FOR SOUTHWESTERN CHESTER 
COUNTY...

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

&&

LAT...LON 3973 7579 3972 7612 3974 7612 3973 7609
      3975 7610 3976 7606 3983 7604 3983 7602
      3985 7602 3985 7601 3987 7600 3987 7599
      3993 7600 3993 7598 3995 7599 4004 7594
      4010 7594 4005 7567 3982 7569

$$

Hoeflich

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 14, 8:16 PM EDTSevere Thunderstorm WarningPHICarbon, Monroe44 min
Jun 14, 9:06 PM EDTSevere Thunderstorm WarningPHIChester54 min
Jun 14, 9:54 PM EDTSevere Thunderstorm WarningPHIChester, Delaware51 min
Jun 14, 10:15 PM EDTFlash Flood WarningPHIChester, Delaware3 hr
Jun 14, 10:21 PM EDTSevere Thunderstorm WarningPHIBucks, Delaware, Montgomery, Philadelphia39 min
Jun 14, 10:26 PM EDTFlash Flood WarningPHIChester, Delaware, Montgomery, Philadelphia3 hr
Jun 14, 10:38 PM EDTFlash Flood WarningPHIDelaware3 hr
Jun 14, 10:44 PM EDTSevere Thunderstorm WarningPHIBucks, Chester, Delaware, Montgomery, Philadelphia46 min
Jun 14, 10:51 PM EDTFlash Flood WarningPHIBucks, Philadelphia3 hr
Jun 14, 10:58 PM EDTSevere Thunderstorm WarningPHIBucks47 min
Jun 14, 11:16 PM EDTSevere Thunderstorm WarningPHIPhiladelphia29 min
Jun 15, 1:37 AM EDTAreal Flood WarningPHIDelaware4 hr
Jun 15, 2:12 AM EDTRiver Flood WarningPHIDelaware2 hr

Nearby

Flash Flood Warnings in Pennsylvania, 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.