Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2019

Severe Thunderstorm Warning 248, NWS Philadelphia/Mount Holly

July 21, 20195 counties in Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 21, 2019, 10:14 PM EDT for 5 counties in Pennsylvania. It was in force for 46 min. 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 21, 2019, 10:14 PM EDT (02:14 UTC)
Expired
Jul 21, 2019, 11:00 PM EDT
In force
46 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

Counties Berks County, PA, Bucks County, PA, Lehigh County, PA, Montgomery County, PA, Northampton County, PA

The radar

The Philadelphia radar (KDIX), 107 km from the middle of the area, began a volume at 02:15 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 21, 10:15 PM EDTTSTM WND GST 70Trexlertown, PACHASER ESTIMATES GUSTS UP TO 70MPH.
Jul 21, 10:25 PM EDTTSTM WND DMGEmmaus, PASEVERAL REPORTS OF TREES AND WIRES DOWN. TIME ESTIMATED FROM RADAR.
Jul 21, 10:25 PM EDTTSTM WND DMGTrexlertown, PAMULTIPLE TRANSFORMERS EXPLODING WITH ESTIMATED GUSTS TO AT LEAST 60MPH.
Jul 21, 10:30 PM EDTTSTM WND DMG1 Ene Salisbury Twp, PADOWNED TREES AND WIRES ON CHURCH RD.
Jul 21, 10:30 PM EDTTSTM WND DMG1 W Salisbury Twp, PADOWNED WIRES ON ELLSWORTH ST.
Jul 21, 11:06 PM EDTTSTM WND DMG1 N Lyons, PADOWNED TREE ON BASTIAN ROAD IN MAXATAWNY TWP. 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 00:00Z, 2.2 hours before the alert went out and 216 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 2019-07-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2295 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 2019-07-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 80 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
2295 J/kg
Mixed-layer CIN
-39 J/kg
Mixed-layer LCL
1588 m above ground
0-6 km bulk shear
29 kt
0-1 km storm-relative helicity
80 m²/s²
0-3 km storm-relative helicity
85 m²/s²
Significant tornado parameter
0.2
Supercell composite
2.4

Open this sounding in Storm Lab

The text

As transmitted.

115 
WUUS51 KPHI 220214
SVRPHI
PAC011-017-077-091-095-220300-
/O.NEW.KPHI.SV.W.0248.190722T0214Z-190722T0300Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
1014 PM EDT Sun Jul 21 2019

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Northeastern Berks County in eastern Pennsylvania...
  Northwestern Montgomery County in southeastern Pennsylvania...
  Southern Lehigh County in eastern Pennsylvania...
  Northwestern Bucks County in southeastern Pennsylvania...
  South central Northampton County in eastern Pennsylvania...

* Until 1100 PM EDT.

* At 1014 PM EDT, a severe thunderstorm was located over Ancient
  Oaks, or 7 miles southwest of Allentown, moving east at 30 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Trained weather spotters.

  IMPACT...Damage to roofs, siding, trees, and power lines is 
           possible.

* Locations impacted include...
  Allentown, Bethlehem, Emmaus, Quakertown, Perkasie, Souderton,
  Bedminster, Hellertown, Kutztown, Fleetwood, Chalfont, East
  Greenville, Dublin, Topton, Leesport, Ferndale, Shoemakersville,
  Bally, Riegelsville and Lyons.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

In addition to large hail and damaging winds, frequent cloud to
ground lightning is occurring with this storm. Move indoors
immediately. Remember, if you can hear thunder, you are close enough
to be struck by lightning.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4061 7592 4060 7519 4057 7519 4057 7516
      4058 7515 4058 7512 4057 7511 4029 7519
      4045 7599
TIME...MOT...LOC 0214Z 279DEG 28KT 4052 7558 

HAIL...<.75IN
WIND...60MPH
 
$$

CMS
3 follow-up statements
569 
WWUS51 KPHI 220227
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
1027 PM EDT Sun Jul 21 2019

PAC011-017-077-091-095-220300-
/O.CON.KPHI.SV.W.0248.000000T0000Z-190722T0300Z/
Berks PA-Montgomery PA-Lehigh PA-Bucks PA-Northampton PA-
1027 PM EDT Sun Jul 21 2019

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1100 PM EDT
FOR NORTHEASTERN BERKS...NORTHWESTERN MONTGOMERY...SOUTHERN LEHIGH...
NORTHWESTERN BUCKS AND SOUTH CENTRAL NORTHAMPTON COUNTIES...

At 1026 PM EDT, a severe thunderstorm was located over Emmaus, or
near Allentown, moving east at 30 mph.

HAZARD...70 mph wind gusts.

SOURCE...Trained weather spotters. There have been several reports 
         of trees down in Lehigh County with this storm.

IMPACT...Expect considerable tree damage. Damage is likely to mobile 
         homes, roofs, and outbuildings.

Locations impacted include...
Allentown, Bethlehem, Emmaus, Quakertown, Perkasie, Souderton,
Bedminster, Hellertown, Kutztown, Fleetwood, Chalfont, East
Greenville, Dublin, Topton, Leesport, Ferndale, Shoemakersville,
Bally, Riegelsville and Lyons.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

Continuous cloud to ground lightning is occurring with this storm.
Move indoors immediately. Lightning is one of nature's leading
killers. Remember, if you can hear thunder, you are close enough to
be struck by lightning.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4061 7592 4060 7519 4057 7519 4057 7516
      4058 7515 4058 7512 4057 7511 4029 7519
      4045 7599
TIME...MOT...LOC 0226Z 269DEG 28KT 4051 7549 

HAIL...<.75IN
WIND...70MPH
 
$$

CMS
292 
WWUS51 KPHI 220248
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
1048 PM EDT Sun Jul 21 2019

PAC011-017-077-091-095-220300-
/O.CON.KPHI.SV.W.0248.000000T0000Z-190722T0300Z/
Berks PA-Montgomery PA-Lehigh PA-Bucks PA-Northampton PA-
1048 PM EDT Sun Jul 21 2019

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1100 PM EDT
FOR NORTHEASTERN BERKS...NORTH CENTRAL MONTGOMERY...SOUTHEASTERN
LEHIGH...NORTHWESTERN BUCKS AND SOUTH CENTRAL NORTHAMPTON COUNTIES...

At 1048 PM EDT, a severe thunderstorm was located over Emmaus, or
near Allentown, moving east at 30 mph.

HAZARD...60 mph wind gusts.

SOURCE...Law enforcement. Numerous reports of wind damage have been 
         received from Lehigh County.

IMPACT...Damage to roofs, siding, trees, and power lines is 
         possible.

Locations impacted include...
Allentown, Bethlehem, Emmaus, Quakertown, Perkasie, Bedminster,
Hellertown, Kutztown, Fleetwood, Chalfont, East Greenville, Dublin,
Topton, Ferndale, Bally, Riegelsville, Lyons, Pleasant Valley, Fricks
and Revere.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

Continuous cloud to ground lightning is occurring with this storm.
Move indoors immediately. Lightning is one of nature's leading
killers. Remember, if you can hear thunder, you are close enough to
be struck by lightning.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4060 7519 4057 7519 4057 7516 4058 7515
      4058 7512 4057 7511 4029 7519 4043 7569
      4047 7586 4061 7574
TIME...MOT...LOC 0248Z 270DEG 28KT 4051 7549 

HAIL...<.75IN
WIND...60MPH
 
$$

CMS
818 
WWUS51 KPHI 220255
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
1055 PM EDT Sun Jul 21 2019

PAC011-017-077-091-095-220305-
/O.EXP.KPHI.SV.W.0248.000000T0000Z-190722T0300Z/
Berks PA-Montgomery PA-Lehigh PA-Bucks PA-Northampton PA-
1055 PM EDT Sun Jul 21 2019

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN BERKS...NORTH
CENTRAL MONTGOMERY...SOUTHEASTERN LEHIGH...NORTHWESTERN BUCKS AND
SOUTH CENTRAL NORTHAMPTON COUNTIES WILL EXPIRE AT 1100 PM EDT...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning will be allowed to expire.  However gusty
winds and heavy rain are still possible with this thunderstorm.

LAT...LON 4060 7519 4057 7519 4057 7516 4058 7515
      4058 7512 4057 7511 4029 7519 4043 7569
      4047 7586 4061 7574
TIME...MOT...LOC 0255Z 279DEG 28KT 4050 7544 

$$

CMS

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 21, 8:25 PM EDTSpecial Weather StatementPHICarbon, Lehigh, Northampton50 min
Jul 21, 8:44 PM EDTSevere Thunderstorm WarningPHIBerks, Carbon, Lehigh, Monroe, Northampton46 min
Jul 21, 9:24 PM EDTSevere Thunderstorm WarningPHIBerks, Bucks, Lehigh, Northampton51 min
Jul 21, 9:30 PM EDTSevere Thunderstorm WarningPHIChester45 min
Jul 21, 9:58 PM EDTAreal Flood AdvisoryPHIBerks, Bucks, Lehigh, Montgomery, Northampton2 hr
Jul 21, 10:30 PM EDTFlash Flood WarningPHIBerks, Lehigh, Northampton3 hr
Jul 21, 10:31 PM EDTFlash Flood WarningPHIBerks, Lehigh, Northampton3 hr
Jul 21, 10:35 PM EDTSevere Thunderstorm WarningPHIBerks, Lehigh40 min
Jul 21, 10:42 PM EDTSevere Thunderstorm WarningPHIBerks, Chester, Montgomery48 min
Jul 21, 10:54 PM EDTSevere Thunderstorm WarningPHIDelaware25 min
Jul 21, 10:58 PM EDTAreal Flood AdvisoryPHIBerks, Chester, Montgomery59 min
Jul 21, 11:05 PM EDTSevere Thunderstorm WarningPHIBerks, Bucks, Lehigh, Montgomery40 min
Jul 21, 11:31 PM EDTSevere Thunderstorm WarningPHIBucks, Montgomery, Philadelphia44 min
Jul 21, 11:38 PM EDTFlash Flood WarningPHIBerks, Carbon, Lehigh, Monroe, Northampton2 hr
Jul 21, 11:40 PM EDTSevere Thunderstorm WarningPHIBerks, Bucks, Carbon, Lehigh, Montgomery, Northampton50 min
Jul 22, 12:05 AM EDTSevere Thunderstorm WarningPHICarbon, Monroe40 min
Jul 22, 12:45 AM EDTSpecial Weather StatementPHIMonroe30 min
Jul 22, 1:11 AM EDTSpecial Weather StatementPHIMonroe34 min
Jul 22, 5:32 AM EDTAreal Flood WarningPHILehigh49 min
Jul 22, 1:28 PM EDTSpecial Weather StatementPHIMonroe32 min
Jul 22, 1:50 PM EDTSpecial Weather StatementPHINorthampton25 min
Jul 22, 3:18 PM EDTSpecial Weather StatementPHIChester57 min
Jul 22, 3:27 PM EDTSevere Thunderstorm WarningPHIMonroe48 min
Jul 22, 3:33 PM EDTAreal Flood AdvisoryPHICarbon, Monroe, Northampton7 hr
Jul 22, 3:39 PM EDTSpecial Weather StatementPHIBerks51 min
Jul 22, 3:47 PM EDTSevere Thunderstorm WarningPHIChester, Delaware58 min
Jul 22, 4:11 PM EDTAreal Flood AdvisoryPHIBerks, Bucks, Chester, Lehigh, Montgomery, Northampton4 hr
Jul 22, 4:16 PM EDTSevere Thunderstorm WarningPHIChester, Delaware59 min
Jul 22, 4:40 PM EDTAreal Flood AdvisoryPHIDelaware, Montgomery, Philadelphia114 min
Jul 22, 4:55 PM EDTSevere Thunderstorm WarningPHIBerks, Bucks, Lehigh, Montgomery, Northampton50 min
Jul 22, 5:04 PM EDTSevere Thunderstorm WarningPHIChester, Delaware, Montgomery, Philadelphia41 min
Jul 22, 5:05 PM EDTFlash Flood WarningPHIBerks, Lehigh, Northampton4 hr
Jul 22, 5:14 PM EDTSevere Thunderstorm WarningPHIBucks, Chester, Delaware, Montgomery, Philadelphia61 min
Jul 22, 5:17 PM EDTSevere Thunderstorm WarningPHIBerks, Bucks, Lehigh, Montgomery, Northampton73 min
Jul 22, 5:34 PM EDTFlash Flood WarningPHIBucks, Lehigh, Montgomery, Northampton4 hr
Jul 22, 5:40 PM EDTSevere Thunderstorm WarningPHIBucks, Philadelphia80 min
Jul 22, 5:43 PM EDTAreal Flood AdvisoryPHIBucks3 hr
Jul 22, 5:50 PM EDTSevere Thunderstorm WarningPHIBucks40 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2019Every severe thunderstorm warning in 2019

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.