Alert archive / Pennsylvania / Flash Flood Warnings in 2024

Flash Flood Warning 60, NWS Philadelphia/Mount Holly

August 18, 2024Warren County, New Jersey; Monroe County, Northampton County, Pennsylvania

NWS Philadelphia/Mount Holly issued this flash flood warning at Aug 18, 2024, 4:56 PM EDT for Warren County, New Jersey; Monroe County, Northampton County, Pennsylvania. It was in force for 6 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 18, 2024, 4:56 PM EDT (20:56 UTC)
Expired
Aug 18, 2024, 11:15 PM EDT
In force
6 hr
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Flood severity
None

Counties Warren County, NJ, Monroe County, PA, Northampton County, PA

The radar

The Philadelphia radar (KDIX), 128 km from the middle of the area, began a volume at 20:56 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 18, 5:30 PM EDTFLASH FLOODBlairstown Twp, NJMultiple reports of flooding in the Blairstown area. Time estimated from radar.

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

The nearest sounding before it

Brookhaven, NY (KOKX), launched 12:00Z, 8.9 hours before the alert went out and 187 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, Brookhaven, NY at 12:00Z on 2024-08-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 109 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, Brookhaven, NY at 12:00Z on 2024-08-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 187 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
109 J/kg
Mixed-layer CIN
-20 J/kg
Mixed-layer LCL
582 m above ground
0-6 km bulk shear
26 kt
0-1 km storm-relative helicity
187 m²/s²
0-3 km storm-relative helicity
205 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.2

Open this sounding in Storm Lab

The text

As transmitted.

949 
WGUS51 KPHI 182056
FFWPHI
NJC041-PAC089-095-190100-
/O.NEW.KPHI.FF.W.0060.240818T2056Z-240819T0100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
456 PM EDT Sun Aug 18 2024

The National Weather Service in Mount Holly has issued a

* Flash Flood Warning for...
  Central Warren County in northwestern New Jersey...
  Northeastern Northampton County in eastern Pennsylvania...
  Southeastern Monroe County in northeastern Pennsylvania...

* Until 900 PM EDT.

* At 456 PM EDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 1.5 and 2.5 inches of 
  rain have fallen. Additional rainfall amounts of 0.5 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...
  East Stroudsburg, Blairstown, Bangor, Pen Argyl, Wind Gap, 
  Belvidere, Harmony, Oxford, Hope, Belfast, Tatamy and East Bangor.

This includes the following highways...
	Interstate 80 in New Jersey between mile markers 0 and 13.
	Interstate 80 in Pennsylvania between mile markers 306 and 314.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Flooding is occurring or is imminent. It is important to know where 
you are relative to streams, rivers, or creeks which can become 
killers in heavy rains. Campers and hikers should avoid streams or 
creeks.

Please report observed flooding to local emergency services or law 
enforcement and request they pass this information to the National 
Weather Service when you can do so safely.

&&

LAT...LON 4107 7521 4111 7506 4109 7504 4108 7503
      4109 7500 4109 7499 4109 7497 4104 7494
      4095 7491 4087 7497 4078 7502 4073 7515
      4072 7525 4085 7533 4098 7532

FLASH FLOOD...RADAR INDICATED

$$

Hoeflich
4 follow-up statements
171 
WGUS71 KPHI 182250
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
650 PM EDT Sun Aug 18 2024

NJC041-PAC089-095-190100-
/O.CON.KPHI.FF.W.0060.000000T0000Z-240819T0100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Warren NJ-Monroe PA-Northampton PA-
650 PM EDT Sun Aug 18 2024

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 9 PM EDT THIS EVENING 
FOR CENTRAL WARREN, NORTHEASTERN NORTHAMPTON AND SOUTHEASTERN MONROE 
COUNTIES...

At 650 PM EDT, emergency management reported thunderstorms producing 
heavy rain in around Blairstown, NJ. Between 2.5 and 4 inches of 
rain have fallen. Additional rainfall amounts up to 1 inch are 
possible in the warned area. Flash flooding is already occurring.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Emergency management reported.

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...
  East Stroudsburg, Blairstown, Bangor, Pen Argyl, Wind Gap, 
  Belvidere, Harmony, Oxford, Hope, Belfast, Tatamy and East Bangor.

This includes the following highways...
	Interstate 80 in New Jersey between mile markers 0 and 13.
	Interstate 80 in Pennsylvania between mile markers 306 and 314.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Flooding is occurring or is imminent. It is important to know where 
you are relative to streams, rivers, or creeks which can become 
killers in heavy rains. Campers and hikers should avoid streams or 
creeks.

Please report observed flooding to local emergency services or law 
enforcement and request they pass this information to the National 
Weather Service when you can do so safely.

&&

LAT...LON 4107 7521 4111 7506 4109 7504 4108 7503
      4109 7500 4109 7499 4109 7497 4104 7494
      4095 7491 4087 7497 4078 7502 4073 7515
      4072 7525 4085 7533 4098 7532

FLASH FLOOD...OBSERVED

$$

Hoeflich
879 
WGUS51 KPHI 190037
FFWPHI
NJC041-PAC089-095-190315-
/O.EXT.KPHI.FF.W.0060.000000T0000Z-240819T0315Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
837 PM EDT Sun Aug 18 2024

The National Weather Service in Mount Holly has extended the

* Flash Flood Warning for...
  Central Warren County in northwestern New Jersey...
  Northeastern Northampton County in eastern Pennsylvania...
  Southeastern Monroe County in northeastern Pennsylvania...

* Until 1115 PM EDT.

* At 837 PM EDT, emergency management reported flooding around 
  Blairstown, NJ and other cities within Warren County. Between 2.5 
  and 4 inches of rain have fallen. Additional rainfall amounts of 1 
  to 2 inches are possible in the warned area as another round of 
  heavy rain moves in. Flash flooding is already occurring.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Emergency management reported.

  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...
  East Stroudsburg, Blairstown, Bangor, Pen Argyl, Wind Gap, 
  Belvidere, Harmony, Oxford, Hope, Belfast, Tatamy and East Bangor.

This includes the following highways...
	Interstate 80 in New Jersey between mile markers 0 and 13.
	Interstate 80 in Pennsylvania between mile markers 306 and 314.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Be especially cautious at night when it is harder to recognize the 
dangers of flooding.

Please report observed flooding to local emergency services or law 
enforcement and request they pass this information to the National 
Weather Service when you can do so safely.

&&

LAT...LON 4107 7521 4111 7506 4109 7504 4108 7503
      4109 7500 4109 7499 4109 7497 4104 7494
      4095 7491 4087 7497 4078 7502 4073 7515
      4072 7525 4085 7533 4098 7532

FLASH FLOOD...OBSERVED

$$

Hoeflich
521 
WGUS71 KPHI 190134
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
934 PM EDT Sun Aug 18 2024

PAC089-190144-
/O.CAN.KPHI.FF.W.0060.000000T0000Z-240819T0315Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Monroe PA-
934 PM EDT Sun Aug 18 2024

...FLASH FLOOD WARNING IS CANCELLED FOR SOUTHEASTERN MONROE COUNTY...

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 Pennsylvania.

&&

LAT...LON 4086 7529 4090 7523 4091 7524 4093 7521
      4096 7513 4097 7512 4097 7513 4099 7513
      4103 7504 4104 7503 4107 7501 4109 7497
      4104 7494 4095 7491 4087 7497 4078 7502
      4073 7515 4072 7525 4085 7533

$$

NJC041-PAC095-190315-
/O.CON.KPHI.FF.W.0060.000000T0000Z-240819T0315Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Warren NJ-Northampton PA-
934 PM EDT Sun Aug 18 2024

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1115 PM EDT THIS 
EVENING FOR CENTRAL WARREN AND NORTHEASTERN NORTHAMPTON COUNTIES...

At 934 PM EDT, emergency management reported thunderstorms producing 
heavy rain with flooding around Blairstown, NJ . Between 2.5 and 4 
inches of rain have fallen. Additional rainfall amounts of 1 to 2 
inches are possible in the warned area. Flash flooding is already 
occurring.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Emergency management reported.

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...
  Blairstown, Bangor, Pen Argyl, Wind Gap, Belvidere, Harmony, 
  Oxford, Hope, Belfast, Tatamy, East Bangor and Delaware Water Gap.

This includes Interstate 80 in New Jersey between mile markers 1 and 
13.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Be especially cautious at night when it is harder to recognize the 
dangers of flooding.

Please report observed flooding to local emergency services or law 
enforcement and request they pass this information to the National 
Weather Service when you can do so safely.

&&

LAT...LON 4086 7529 4090 7523 4091 7524 4093 7521
      4096 7513 4097 7512 4097 7513 4099 7513
      4103 7504 4104 7503 4107 7501 4109 7497
      4104 7494 4095 7491 4087 7497 4078 7502
      4073 7515 4072 7525 4085 7533

FLASH FLOOD...OBSERVED

$$

Hoeflich
955 
WGUS71 KPHI 190305
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
1105 PM EDT Sun Aug 18 2024

NJC041-PAC095-190315-
/O.EXP.KPHI.FF.W.0060.000000T0000Z-240819T0315Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Warren NJ-Northampton PA-
1105 PM EDT Sun Aug 18 2024

...FLASH FLOOD WARNING WILL EXPIRE AT 1115 PM EDT THIS EVENING FOR 
CENTRAL WARREN AND NORTHEASTERN NORTHAMPTON 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 200 AM EDT for portions of 
northern Delaware, New Jersey, and Pennsylvania.

&&

LAT...LON 4086 7529 4090 7523 4091 7524 4093 7521
      4096 7513 4097 7512 4097 7513 4099 7513
      4103 7504 4104 7503 4107 7501 4109 7497
      4104 7494 4095 7491 4087 7497 4078 7502
      4073 7515 4072 7525 4085 7533

$$

Hoeflich

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 18, 3:09 AM EDTFlash Flood WarningPHIBurlington, Camden93 min
Aug 18, 4:41 AM EDTFlash Flood WarningPHIBurlington, Camden, Mercer2 hr
Aug 18, 2:17 PM EDTSpecial Marine WarningPHI58 min
Aug 18, 2:42 PM EDTSpecial Marine WarningPHI93 min
Aug 18, 3:55 PM EDTSpecial Marine WarningPHI95 min
Aug 18, 4:04 PM EDTSevere Thunderstorm WarningPHIWarren41 min
Aug 18, 4:41 PM EDTSevere Thunderstorm WarningPHISussex, Warren34 min
Aug 18, 5:10 PM EDTSevere Thunderstorm WarningPHIHunterdon, Morris, Warren29 min
Aug 18, 5:21 PM EDTSevere Thunderstorm WarningPHIBurlington, Camden39 min
Aug 18, 5:31 PM EDTFlash Flood WarningPHIHunterdon, Warren6 hr
Aug 18, 5:38 PM EDTFlash Flood WarningPHISussex, Warren4 hr
Aug 18, 5:47 PM EDTSevere Thunderstorm WarningPHIMorris, Sussex43 min
Aug 18, 5:47 PM EDTSevere Thunderstorm WarningPHIBurlington, Mercer, Middlesex, Monmouth58 min
Aug 18, 5:51 PM EDTSevere Thunderstorm WarningPHIMorris, Somerset24 min
Aug 18, 5:59 PM EDTSevere Thunderstorm WarningPHIMorris, Sussex18 min
Aug 18, 6:01 PM EDTFlash Flood WarningPHIHunterdon, Morris, Somerset, Sussex, Warren6 hr
Aug 18, 6:24 PM EDTSevere Thunderstorm WarningPHIMiddlesex, Morris, Somerset66 min
Aug 18, 6:36 PM EDTFlash Flood WarningPHIMorris, Somerset5 hr
Aug 18, 1:35 AM EDTFlash Flood WarningPHIBucks, Delaware, Montgomery, Philadelphia2 hr
Aug 18, 3:24 PM EDTSevere Thunderstorm WarningPHIMonroe, Northampton19 min
Aug 18, 3:34 PM EDTSevere Thunderstorm WarningPHIChester, Delaware, Montgomery, Philadelphia41 min
Aug 18, 3:48 PM EDTSevere Thunderstorm WarningPHICarbon, Monroe42 min
Aug 18, 4:25 PM EDTSevere Thunderstorm WarningPHIBucks, Lehigh, Montgomery, Northampton28 min

Nearby

Flash Flood Warnings in Pennsylvania, 2024Flash Flood Warnings in New Jersey, 2024Every flash flood warning in 2024

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.