Alert archive / Pennsylvania / Flash Flood Warnings in 2022

Flash Flood Warning 5, NWS Philadelphia/Mount Holly

July 2, 2022Chester County, Pennsylvania

NWS Philadelphia/Mount Holly issued this flash flood warning at Jul 2, 2022, 5:16 PM EDT for Chester County, Pennsylvania. It was in force for 4 hr. 6 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 2, 2022, 5:16 PM EDT (21:16 UTC)
Expired
Jul 2, 2022, 8:54 PM EDT
In force
4 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), 115 km from the middle of the area, began a volume at 21:17 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
Jul 2, 6:00 PM EDTFLASH FLOOD1 Wnw Nottingham, PAFIRE DEPARTMENT REPORTS WATER RESCUE IN WEST NOTTINGHAM TWP.
Jul 2, 6:34 PM EDTHEAVY RAIN 3.231 Ese Oxford, PAWUNDERGROUND GAUGE KPAOXFOR48 STORM TOTAL IN JUST OVER TWO HOURS.
Jul 2, 6:44 PM EDTHEAVY RAIN 4.04Oxford, PAWUNDERGROUND GAUGE KPAOXFOR22 STORM TOTAL IN JUST LESS THAN TWO AND A HALF HOURS.
Jul 2, 6:54 PM EDTHEAVY RAIN 3.99Nottingham, PAWUNDERGROUND GAUGE KPANOTTI11 STORM TOTAL IN A LITTLE OVER TWO AND A HALF HOURS.
Jul 2, 6:55 PM EDTHEAVY RAIN 4.22Nottingham, PATOTAL RAINFALL IN JUST OVER TWO AND A HALF HOURS.
Jul 2, 6:56 PM EDTHEAVY RAIN 3.261 S Oxford, PAWUNDERGROUND GAUGE KPAOXFOR39 STORM TOTAL IN ABOUT TWO AND A HALF HOURS.

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, 9.3 hours before the alert went out and 146 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 2022-07-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 499 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 12:00Z on 2022-07-02The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 28 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
499 J/kg
Mixed-layer CIN
-137 J/kg
Mixed-layer LCL
1039 m above ground
0-6 km bulk shear
21 kt
0-1 km storm-relative helicity
28 m²/s²
0-3 km storm-relative helicity
88 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

As transmitted.

529 
WGUS51 KPHI 022116
FFWPHI
PAC029-030115-
/O.NEW.KPHI.FF.W.0005.220702T2116Z-220703T0115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
516 PM EDT Sat Jul 2 2022

The National Weather Service in Mount Holly has issued a

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

* Until 915 PM EDT.

* At 516 PM EDT, Doppler radar and automated rain gauges indicated 
  thunderstorms producing heavy rain across the warned area. Between 
  1 and 2 inches of rain have fallen. Additional rainfall amounts of 
  0.5 to 1.5 inches are possible in the warned area. Flash flooding 
  is ongoing or expected to begin shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar and automated gauges.

  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...
  Oxford, Mount Vernon, and Glen Roy.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3973 7611 3973 7612 3974 7612 3974 7611
      3975 7610 3974 7609 3975 7608 3976 7608
      3976 7606 3977 7606 3981 7603 3981 7587
      3977 7587 3973 7591 3972 7598 3972 7605
      3973 7610 3973 7609 3974 7610

FLASH FLOOD...RADAR AND GAUGE INDICATED

$$

Staarmann
3 follow-up statements
143 
WGUS71 KPHI 022156
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
556 PM EDT Sat Jul 2 2022

PAC029-030115-
/O.CON.KPHI.FF.W.0005.000000T0000Z-220703T0115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Chester PA-
556 PM EDT Sat Jul 2 2022

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 915 PM EDT THIS 
EVENING FOR SOUTHWESTERN CHESTER COUNTY...

At 556 PM EDT, Doppler radar and automated rain gauges indicated 
thunderstorms producing heavy rain across the warned area. Between 
1.5 and 3 inches of rain have fallen. 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 and automated gauges.

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...
  Oxford, Mount Vernon, and Glen Roy.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3973 7611 3973 7612 3974 7612 3974 7611
      3975 7610 3974 7609 3975 7608 3976 7608
      3976 7606 3977 7606 3981 7603 3981 7587
      3977 7587 3973 7591 3972 7598 3972 7605
      3973 7610 3973 7609 3974 7610

FLASH FLOOD...RADAR AND GAUGE INDICATED

$$

Staarmann
675 
WGUS71 KPHI 022222
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
622 PM EDT Sat Jul 2 2022

PAC029-030115-
/O.CON.KPHI.FF.W.0005.000000T0000Z-220703T0115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Chester PA-
622 PM EDT Sat Jul 2 2022

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 915 PM EDT THIS 
EVENING FOR SOUTHWESTERN CHESTER COUNTY...

At 622 PM EDT, local law enforcement reported thunderstorms 
producing heavy rain across the warned area. Between 2 and 3 inches 
of rain have fallen. 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...Law enforcement 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...
  Oxford, Mount Vernon, and Glen Roy.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Motorists should not attempt to drive around barricades or drive 
cars through flooded areas.

&&

LAT...LON 3973 7611 3973 7612 3974 7612 3974 7611
      3975 7610 3974 7609 3975 7608 3976 7608
      3976 7606 3977 7606 3981 7603 3981 7587
      3977 7587 3973 7591 3972 7598 3972 7605
      3973 7610 3973 7609 3974 7610

FLASH FLOOD...OBSERVED

$$

Staarmann
910 
WGUS71 KPHI 030054
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
854 PM EDT Sat Jul 2 2022

PAC029-030104-
/O.CAN.KPHI.FF.W.0005.000000T0000Z-220703T0115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Chester PA-
854 PM EDT Sat Jul 2 2022

...FLASH FLOOD WARNING FOR SOUTHWESTERN CHESTER COUNTY HAS BEEN 
REPLACED WITH A FLOOD WARNING...

LAT...LON 3973 7611 3973 7612 3974 7612 3974 7611
      3975 7610 3974 7609 3975 7608 3976 7608
      3976 7606 3977 7606 3981 7603 3981 7587
      3977 7587 3973 7591 3972 7598 3972 7605
      3973 7610 3973 7609 3974 7610

$$

RCM

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 2, 3:45 PM EDTSevere Thunderstorm WarningPHIChester60 min
Jul 2, 4:48 PM EDTSevere Thunderstorm WarningPHIChester24 min
Jul 2, 4:50 PM EDTAreal Flood AdvisoryPHIChester26 min
Jul 2, 5:19 PM EDTSpecial Weather StatementPHIChester56 min
Jul 2, 7:11 PM EDTSpecial Weather StatementPHIBerks64 min

Nearby

Flash Flood Warnings in Pennsylvania, 2022Every flash flood warning in 2022

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.