Alert archive / Pennsylvania / Flash Flood Warnings in 2021

Flash Flood Warning 56, NWS Philadelphia/Mount Holly

August 22, 2021Monroe County, Northampton County, Pennsylvania; Sussex County, Warren County, New Jersey

NWS Philadelphia/Mount Holly issued this flash flood warning at Aug 22, 2021, 8:47 PM EDT for Monroe County, Northampton County, Pennsylvania; Sussex County, Warren County, New Jersey. It was in force for 6 hr. 11 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
Aug 22, 2021, 8:47 PM EDT (00:47 UTC)
Expired
Aug 23, 2021, 2:45 AM EDT
In force
6 hr
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Flood severity
None

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

The radar

The Binghamton radar (KBGM), 141 km from the middle of the area, began a volume at 00:46 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 22, 9:26 PM EDTFLASH FLOODMiddle Smithfield Towns, PAVEHICLES SUBMERGED IN RISING WATERS. BROWNOUTS AND FLOODED BASEMENTS.
Aug 22, 9:26 PM EDTFLASH FLOODSmithfield Twp, PAVEHICLES SUBMERGED IN RISING WATERS. BROWNOUTS AND FLOODED BASEMENTS.
Aug 22, 9:26 PM EDTFLASH FLOODStroud Twp, PAVEHICLES SUBMERGED IN RISING WATERS. BROWNOUTS AND FLOODED BASEMENTS.
Aug 22, 10:14 PM EDTFLASH FLOOD2 Se Delaware Water Gap, PAFLOODING ON PA 611 BOTH DIRECTIONS BETWEEN STATE PARK AND MOUNTAIN RD, WARING DR. ALL LANES CLOSED.
Aug 22, 10:29 PM EDTFLASH FLOODTannersville, PAFLOODING ON I-80 EASTBOUND BETWEEN EXIT 299: PA 715 - TANNERSVILLE AND EXIT 302B: PA 611 - BARTONSVILLE. ALL LANES CLOSED.
Aug 22, 10:47 PM EDTFLASH FLOOD3 Ssw Upper Mount Bethe, PAPA 611 CLOSED IN BOTH DIRECTIONS BETWEEN RIVERTON RD AND STATE PARK RD DUE TO FLOODING. ALL LANES CLOSED.
Aug 23, 12:00 AM EDTFLASH FLOOD2 W Smithfield Twp, PAFLASH FLOODING ON LITTLE SAMBO CREEK. PROPERTY DAMAGE ADJACENT TO ITS BANKS.
Aug 23, 12:00 AM EDTHEAVY RAIN 4.86Stroudsburg, PASTORM TOTAL SO FAR.
Aug 23, 12:00 AM EDTHEAVY RAIN 4.952 W Smithfield Twp, PALITTLE SAMBO CREEK IS FLOODING WITH WATER AFFECTING RESIDENCES ON ITS BANKS.
Aug 23, 12:39 AM EDTFLASH FLOOD1 Ese Jackson Twp, PAMILLER ROAD AND GOLDEN SLIPPER ROAD CLOSED DUE TO FLOODING. ALL LANES CLOSED.
Aug 23, 1:30 AM EDTFLOOD2 Nne Echo Lake, PATHE GAUGE ON BUSH KILL AT SHOEMAKERS (SHOP1) REACHED FLOOD STAGE.

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 00:00Z, 0.8 hours before the alert went out and 197 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 00:00Z on 2021-08-23Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 59 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 00:00Z on 2021-08-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -22 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
59 J/kg
Mixed-layer CIN
-168 J/kg
Mixed-layer LCL
610 m above ground
0-6 km bulk shear
21 kt
0-1 km storm-relative helicity
-22 m²/s²
0-3 km storm-relative helicity
-66 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.0

Open this sounding in Storm Lab

The text

As transmitted.

990 
WGUS51 KPHI 230047
FFWPHI
NJC037-041-PAC089-095-230645-
/O.NEW.KPHI.FF.W.0056.210823T0047Z-210823T0645Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
847 PM EDT Sun Aug 22 2021

The National Weather Service in Mount Holly has issued a

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

* Until 245 AM EDT.

* At 847 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 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 will experience flash flooding include...
  Mount Pocono, East Stroudsburg, Tobyhanna, Blairstown, Bangor, Pen 
  Argyl, Wind Gap, East Bangor, Delaware Water Gap, Analomink, 
  Henryville, and Tannersville.

This includes the following highways...
	Interstate 80 in New Jersey between mile markers 0 and 11.
	Interstate 80 in Pennsylvania between mile markers 289 and 314.
	Interstate 380 in Pennsylvania between mile markers 0 and 12.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Be aware of your surroundings and do not drive on flooded roads.

In hilly terrain there are hundreds of low water crossings which are 
potentially dangerous in heavy rain. Do not attempt to cross flooded 
roads. Find an alternate route.

&&

LAT...LON 4114 7562 4122 7554 4125 7513 4115 7516
      4114 7508 4108 7503 4112 7495 4107 7482
      4096 7492 4086 7510 4079 7535

FLASH FLOOD...RADAR INDICATED

$$

Meola

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 22, 8:11 PM EDTAreal Flood AdvisoryPHICarbon, Monroe, Northampton6 hr
Aug 22, 10:34 PM EDTAreal Flood AdvisoryPHICarbon, Lehigh, Northampton3 hr
Aug 22, 10:53 PM EDTFlash Flood WarningPHICarbon, Lehigh, Monroe, Montgomery, Northampton4 hr
Aug 22, 11:42 PM EDTAreal Flood AdvisoryPHIBerks3 hr
Aug 23, 12:32 AM EDTRiver Flood WarningPHIMonroe10 hr
Aug 23, 12:55 AM EDTRiver Flood WarningPHIMonroe10 hr
Aug 23, 2:36 AM EDTAreal Flood WarningPHICarbon, Monroe21 hr
Aug 23, 3:50 AM EDTRiver Flood WarningPHICarbon3 hr
Aug 23, 3:50 AM EDTRiver Flood WarningPHILehigh, Northampton11 hr
Aug 23, 8:28 AM EDTAreal Flood WarningPHILehigh7 hr
Aug 23, 4:41 PM EDTSpecial Weather StatementPHIMontgomery34 min
Aug 22, 11:27 PM EDTAreal Flood WarningPHIMiddlesex29 hr
Aug 23, 2:09 AM EDTRiver Flood WarningPHIMorris, Passaic17 hr
Aug 23, 3:25 AM EDTAreal Flood WarningPHIMorris8 hr
Aug 23, 4:10 AM EDTRiver Flood WarningPHIMorris41 hr
Aug 23, 5:07 AM EDTAreal Flood WarningPHIWarren21 hr
Aug 23, 5:22 AM EDTAreal Flood WarningPHISomerset9 hr
Aug 23, 5:44 AM EDTAreal Flood WarningPHIHunterdon7 hr
Aug 23, 7:20 AM EDTRiver Flood WarningPHIHunterdon, Somerset7 hr
Aug 23, 7:47 AM EDTRiver Flood WarningPHIMorris, Passaic13 hr
Aug 23, 8:36 AM EDTAreal Flood WarningPHISomerset9 hr
Aug 23, 8:42 AM EDTRiver Flood WarningPHIMiddlesex, Somerset21 hr
Aug 23, 11:22 AM EDTRiver Flood WarningPHIMiddlesex, Somerset16 hr
Aug 23, 11:32 AM EDTRiver Flood WarningPHIEssex, Morris, Passaic5 days
Aug 23, 11:58 AM EDTRiver Flood WarningPHISomerset15 hr
Aug 23, 12:19 PM EDTRiver Flood WarningPHIBurlington33 hr
Aug 23, 12:51 PM EDTCoastal Flood StatementPHIOcean3 hr
Aug 23, 2:26 PM EDTAreal Flood WarningPHISussex14 hr
Aug 23, 2:26 PM EDTSpecial Weather StatementPHIOcean49 min
Aug 23, 3:12 PM EDTSpecial Weather StatementPHIOcean33 min
Aug 23, 3:15 PM EDTSevere Thunderstorm WarningPHIOcean45 min
Aug 23, 3:18 PM EDTSpecial Marine WarningPHI57 min
Aug 23, 3:38 PM EDTRiver Flood WarningPHIEssex, Morris, Passaic48 hr
Aug 23, 4:47 PM EDTSpecial Weather StatementPHIAtlantic28 min
Aug 23, 4:50 PM EDTSpecial Marine WarningPHI55 min
Aug 23, 5:13 PM EDTSpecial Weather StatementPHICamden32 min
Aug 23, 5:39 PM EDTSpecial Marine WarningPHI33 min
Aug 23, 6:46 PM EDTSpecial Marine WarningPHI64 min

Nearby

Flash Flood Warnings in Pennsylvania, 2021Flash Flood Warnings in New Jersey, 2021Every flash flood warning in 2021

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.