Alert archive / Pennsylvania / Flash Flood Warnings in 2021

Flash Flood Warning 5, NWS Pittsburgh, PA

June 13, 2021Allegheny County, Westmoreland County, Pennsylvania

NWS Pittsburgh, PA issued this flash flood warning at Jun 13, 2021, 5:29 PM EDT for Allegheny County, Westmoreland County, Pennsylvania. It was in force for 3 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
Jun 13, 2021, 5:29 PM EDT (21:29 UTC)
Expired
Jun 13, 2021, 8:45 PM EDT
In force
3 hr
Issued by
NWS Pittsburgh, PA
Area
Storm-based polygon
Flood severity
None

Counties Allegheny County, PA, Westmoreland County, PA

The radar

The Pittsburgh radar (KPBZ), 41 km from the middle of the area, began a volume at 21:29 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
Jun 13, 6:15 PM EDTFLOODSquirrel Hill, PAMINOR STREET FLOODING
Jun 13, 6:16 PM EDTFLOODSwissvale, PAMINOR STREET FLOODING
Jun 13, 6:30 PM EDTFLOOD4 Nw West Mifflin, PAWIDESPREAD FLOODING
Jun 13, 6:30 PM EDTFLASH FLOOD1 N Monroeville, PAINTERSTATE 376 EAST ON RAMP AT MONROEVILLE FLOODED WITH STRANDED CAR. TIME ESTIMATED.
Jun 13, 6:30 PM EDTFLASH FLOODMunhall, PAREPORT OF 7 FOOT DEEP WATER OVER ROADWAY IN MUNHALL.
Jun 13, 6:30 PM EDTHEAVY RAIN 2.02N Baldwin, PA
Jun 13, 6:45 PM EDTFLASH FLOODWest Mifflin, PANUMEROUS REPORTS OF VEHICLES STUCK IN FLOOD WATERS ACROSS THE COUNTY AND AROUND PITTSBURGH.
Jun 13, 6:55 PM EDTFLASH FLOODWhitehall, PAINTERSECTION OF PROVOST AND WAYMAN FLOODED BY NEARBY SAW MILL RUN BEING OUT OF ITS BANKS.
Jun 13, 7:15 PM EDTFLASH FLOODBaldwin, PAWATER RESCUE OF SEVERAL PEOPLE TRAPPED IN VEHICLES IN THE VICINITY OF 4846 STREETS RUN RD.
Jun 13, 7:15 PM EDTFLASH FLOODPleasant Hills, PAMULTIPLE VEHICLES TRAPPED IN FLOOD WATERS OF CLAIRTON BLVD AND LEWIS RUN RD.
Jun 13, 7:26 PM EDTFLOODW Castle Shannon, PAMINOR STREET FLOODING

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

The nearest sounding before it

Pittsburgh, PA (KPIT), launched 12:00Z, 9.5 hours before the alert went out and 25 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, Pittsburgh, PA at 12:00Z on 2021-06-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1001 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, Pittsburgh, PA at 12:00Z on 2021-06-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 53 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
1001 J/kg
Mixed-layer CIN
-33 J/kg
Mixed-layer LCL
944 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
53 m²/s²
0-3 km storm-relative helicity
47 m²/s²
Significant tornado parameter
0.2
Supercell composite
1.3

Open this sounding in Storm Lab

The text

As transmitted.

923 
WGUS51 KPBZ 132129
FFWPBZ
PAC003-129-132330-
/O.NEW.KPBZ.FF.W.0005.210613T2129Z-210613T2330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Pittsburgh PA
529 PM EDT Sun Jun 13 2021

The National Weather Service in Pittsburgh has issued a

* Flash Flood Warning for...
  Southeastern Allegheny County in southwestern Pennsylvania...
  Southwestern Westmoreland County in southwestern Pennsylvania...

* Until 730 PM EDT.

* At 529 PM EDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Up to 1 inch of rain has 
  fallen. Flash flooding is ongoing or expected to begin shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar.

  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...
  Pittsburgh, Penn Hills, Mount Lebanon, Bethel Park, Monroeville, 
  Greensburg, McKeesport, Jeannette, West Mifflin, Baldwin, 
  Murrysville, Wilkinsburg, Whitehall, South Park Township, Munhall, 
  Jefferson Hills, North Versailles, Brentwood, Swissvale and Castle 
  Shannon.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

&&

LAT...LON 4020 7986 4024 7992 4025 7991 4027 7995
      4038 8004 4045 7995 4044 7974 4037 7949
      4013 7976

FLASH FLOOD...RADAR INDICATED

$$
5 follow-up statements
983 
WGUS71 KPBZ 132222
FFSPBZ

Flash Flood Statement
National Weather Service Pittsburgh PA
622 PM EDT Sun Jun 13 2021

PAC003-129-132330-
/O.CON.KPBZ.FF.W.0005.000000T0000Z-210613T2330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Allegheny PA-Westmoreland PA-
622 PM EDT Sun Jun 13 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 730 PM EDT THIS 
EVENING FOR SOUTHEASTERN ALLEGHENY AND SOUTHWESTERN WESTMORELAND 
COUNTIES...

At 622 PM EDT, Doppler radar indicated thunderstorms producing heavy 
rain across the warned area. Between 0.5 and 1.5 inches of rain have 
fallen. An additional 1 to 2 inches are possible.  Flash flooding is 
ongoing or expected to begin shortly.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Radar.

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...
  Pittsburgh, Penn Hills, Mount Lebanon, Bethel Park, Monroeville, 
  Greensburg, McKeesport, Jeannette, West Mifflin, Baldwin, 
  Murrysville, Wilkinsburg, Whitehall, South Park Township, Munhall, 
  Jefferson Hills, North Versailles, Brentwood, Swissvale and Castle 
  Shannon.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

&&

LAT...LON 4020 7986 4024 7992 4025 7991 4027 7995
      4038 8004 4045 7995 4044 7974 4037 7949
      4013 7976

FLASH FLOOD...RADAR INDICATED

$$
116 
WGUS71 KPBZ 132305
FFSPBZ

Flash Flood Statement
National Weather Service Pittsburgh PA
705 PM EDT Sun Jun 13 2021

PAC003-129-132330-
/O.CON.KPBZ.FF.W.0005.000000T0000Z-210613T2330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Allegheny PA-Westmoreland PA-
705 PM EDT Sun Jun 13 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 730 PM EDT THIS 
EVENING FOR SOUTHEASTERN ALLEGHENY AND SOUTHWESTERN WESTMORELAND 
COUNTIES...

At 705 PM EDT, Public reports indicate flooding in Castle Shannon 
and Whitehall. Between 1.5 and 3 inches of rain have fallen.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Public reported.

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...
  Pittsburgh, Penn Hills, Mount Lebanon, Bethel Park, Monroeville, 
  Greensburg, McKeesport, Jeannette, West Mifflin, Baldwin, 
  Murrysville, Wilkinsburg, Whitehall, South Park Township, Munhall, 
  Jefferson Hills, North Versailles, Brentwood, Swissvale and Castle 
  Shannon.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

&&

LAT...LON 4020 7986 4024 7992 4025 7991 4027 7995
      4038 8004 4045 7995 4044 7974 4037 7949
      4013 7976

FLASH FLOOD...OBSERVED

$$
501 
WGUS51 KPBZ 132324
FFWPBZ
PAC003-129-140000-
/O.EXT.KPBZ.FF.W.0005.000000T0000Z-210614T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Pittsburgh PA
724 PM EDT Sun Jun 13 2021

The National Weather Service in Pittsburgh has extended the

* Flash Flood Warning for...
  Southeastern Allegheny County in southwestern Pennsylvania...
  Southwestern Westmoreland County in southwestern Pennsylvania...

* Until 800 PM EDT.

* At 724 PM EDT, Public reports indicate flooding in Castle Shannon 
  and Whitehall as well as numerous roadways across the region.  
  Warning has been extended to allow more time for water to recede. 
  Between 1.5 and 3 inches of rain have fallen.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Public reported.

  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...
  Pittsburgh, Penn Hills, Mount Lebanon, Bethel Park, Monroeville, 
  Greensburg, McKeesport, Jeannette, West Mifflin, Baldwin, 
  Murrysville, Wilkinsburg, Whitehall, South Park Township, Munhall, 
  Jefferson Hills, North Versailles, Brentwood, Swissvale and Castle 
  Shannon.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

&&

LAT...LON 4020 7986 4024 7992 4025 7991 4027 7995
      4038 8004 4045 7995 4044 7974 4037 7949
      4013 7976

FLASH FLOOD...OBSERVED

$$
510 
WGUS51 KPBZ 132349
FFWPBZ
PAC003-129-140045-
/O.EXT.KPBZ.FF.W.0005.000000T0000Z-210614T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Pittsburgh PA
749 PM EDT Sun Jun 13 2021

The National Weather Service in Pittsburgh has extended the

* Flash Flood Warning for...
  Southeastern Allegheny County in southwestern Pennsylvania...
  Southwestern Westmoreland County in southwestern Pennsylvania...

* Until 845 PM EDT.

* At 749 PM EDT, Emergency management have reported multiple water 
  rescues around Pittsburgh and notably in Pleasant Hills.  The 
  warning has been extended to give time for more water to recede.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Emergency management reported.

  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...
  Pittsburgh, Penn Hills, Mount Lebanon, Bethel Park, Monroeville, 
  Greensburg, McKeesport, Jeannette, West Mifflin, Baldwin, 
  Murrysville, Wilkinsburg, Whitehall, South Park Township, Munhall, 
  Jefferson Hills, North Versailles, Brentwood, Swissvale and Castle 
  Shannon.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

&&

LAT...LON 4020 7986 4024 7992 4025 7991 4027 7995
      4038 8004 4045 7995 4044 7974 4037 7949
      4013 7976

FLASH FLOOD...OBSERVED

$$
900 
WGUS71 KPBZ 140051
FFSPBZ

Flash Flood Statement
National Weather Service Pittsburgh PA
851 PM EDT Sun Jun 13 2021

PAC003-129-140101-
/O.EXP.KPBZ.FF.W.0005.000000T0000Z-210614T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Allegheny PA-Westmoreland PA-
851 PM EDT Sun Jun 13 2021

...FLASH FLOOD WARNING HAS EXPIRED FOR SOUTHEASTERN ALLEGHENY AND 
SOUTHWESTERN WESTMORELAND COUNTIES...

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 4020 7986 4024 7992 4025 7991 4027 7995
      4038 8004 4045 7995 4044 7974 4037 7949
      4013 7976

$$

The office that day

Everything else NWS Pittsburgh, PA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 13, 8:24 AM EDTSpecial Weather StatementPBZWestmoreland36 min
Jun 13, 8:36 AM EDTAreal Flood AdvisoryPBZArmstrong, Westmoreland71 min
Jun 13, 8:51 AM EDTAreal Flood AdvisoryPBZArmstrong, Indiana103 min
Jun 13, 9:02 AM EDTSpecial Weather StatementPBZWestmoreland13 min
Jun 13, 9:39 AM EDTSpecial Weather StatementPBZFayette36 min
Jun 13, 10:42 AM EDTSpecial Weather StatementPBZFayette33 min
Jun 13, 1:37 PM EDTSevere Thunderstorm WarningPBZGreene38 min
Jun 13, 1:57 PM EDTSevere Thunderstorm WarningPBZGreene20 min
Jun 13, 2:08 PM EDTSevere Thunderstorm WarningPBZGreene33 min
Jun 13, 3:55 PM EDTSevere Thunderstorm WarningPBZButler, Lawrence, Mercer35 min
Jun 13, 4:23 PM EDTSevere Thunderstorm WarningPBZBeaver, Butler, Lawrence37 min
Jun 13, 5:33 PM EDTSevere Thunderstorm WarningPBZAllegheny, Beaver, Butler, Westmoreland27 min
Jun 13, 5:43 PM EDTSevere Thunderstorm WarningPBZIndiana, Westmoreland47 min
Jun 13, 5:53 PM EDTSevere Thunderstorm WarningPBZClarion, Forest, Venango17 min
Jun 13, 5:59 PM EDTSevere Thunderstorm WarningPBZAllegheny, Washington, Westmoreland46 min
Jun 13, 6:12 PM EDTSpecial Weather StatementPBZForest33 min
Jun 13, 6:21 PM EDTSevere Thunderstorm WarningPBZGreene, Washington39 min
Jun 13, 6:54 PM EDTAreal Flood AdvisoryPBZAllegheny, Washington, Westmoreland2 hr
Jun 13, 6:58 PM EDTSpecial Weather StatementPBZWashington47 min
Jun 13, 7:22 PM EDTFlash Flood WarningPBZAllegheny, Washington100 min
Jun 13, 7:26 PM EDTSpecial Weather StatementPBZFayette34 min

Nearby

Flash Flood Warnings in Pennsylvania, 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.