Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2022

Severe Thunderstorm Warning 37, NWS Philadelphia/Mount Holly

May 20, 20224 counties in Pennsylvania; Gloucester County, New Jersey; New Castle County, Delaware

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at May 20, 2022, 2:27 PM EDT for 4 counties in Pennsylvania; Gloucester County, New Jersey; New Castle County, Delaware. It was in force for 48 min. 20 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
May 20, 2022, 2:27 PM EDT (18:27 UTC)
Expired
May 20, 2022, 3:15 PM EDT
In force
48 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Hail
0.88 in
Wind
60.0 mph

Counties New Castle County, DE, Gloucester County, NJ, Chester County, PA, Delaware County, PA, Montgomery County, PA, Philadelphia County, PA

The radar

The Philadelphia radar (KDIX), 77 km from the middle of the area, began a volume at 18:28 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
May 20, 2:28 PM EDTHAIL 0.7Chadds Ford Twp, PA
May 20, 2:32 PM EDTHAIL 0.25Chadds Ford Twp, PA
May 20, 2:35 PM EDTHAIL 0.25Glen Mills, PA
May 20, 2:35 PM EDTHAIL 0.25Upper Chichester Twp, PA
May 20, 2:35 PM EDTHAIL 0.71 N Glen Mills, PA
May 20, 2:36 PM EDTHAIL 0.88Talleyville, DE
May 20, 2:50 PM EDTHAIL 1Green Ridge, PAREPORT FROM MPING: QUARTER (1.00 IN.).
May 20, 2:54 PM EDTHAIL 1.25Swarthmore, PA
May 20, 2:55 PM EDTHAIL 0.88Ridley Twp., PA
May 20, 2:57 PM EDTHAIL 1Aston Twp., PA
May 20, 3:00 PM EDTHAIL 1Upper Darby, PA
May 20, 3:00 PM EDTHAIL 1.5Folsom, PA
May 20, 3:01 PM EDTHAIL 0.88Secane, PA
May 20, 3:02 PM EDTHAIL 0.88Clifton Heights, PA
May 20, 3:04 PM EDTHAIL 0.75Morton, PAREPORT FROM MPING: DIME (0.75 IN.).
May 20, 3:10 PM EDTHAIL 0.751 Se Point Breeze, PAREPORT FROM MPING: DIME (0.75 IN.).
May 20, 3:15 PM EDTHAIL 0.882 E South Philadelphia, PA
May 20, 3:15 PM EDTHAIL 1.251 Sse Point Breeze, PAHAIL UP TO HALF DOLLAR SIZE IN SOUTH PHILLY. TIME ESTIMATED FROM RADAR.
May 20, 3:16 PM EDTHAIL 12 Ese Point Breeze, PAHAIL AROUND 1 INCH DIAMETER NEAR DICKINSON SQUARE PARK IN SOUTH PHILLY.
May 20, 3:20 PM EDTHAIL 11 Sse Point Breeze, PA

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

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
May 20, 11:35 AM EDTTornado WatchSPC7 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 6.5 hours before the alert went out and 209 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 2022-05-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1 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 2022-05-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 106 square meters per square second.19395878Sfc1 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
1 J/kg
Mixed-layer CIN
-226 J/kg
Mixed-layer LCL
1469 m above ground
0-6 km bulk shear
34 kt
0-1 km storm-relative helicity
106 m²/s²
0-3 km storm-relative helicity
169 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.2

Open this sounding in Storm Lab

The text

As transmitted.

219 
WUUS51 KPHI 201827
SVRPHI
DEC003-NJC015-PAC029-045-091-101-201915-
/O.NEW.KPHI.SV.W.0037.220520T1827Z-220520T1915Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
227 PM EDT Fri May 20 2022

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Northeastern New Castle County in northern Delaware...
  Northwestern Gloucester County in southern New Jersey...
  South central Montgomery County in southeastern Pennsylvania...
  Southeastern Chester County in southeastern Pennsylvania...
  Southwestern Philadelphia County in southeastern Pennsylvania...
  Delaware County in southeastern Pennsylvania...

* Until 315 PM EDT.

* At 227 PM EDT, a severe thunderstorm was located over Ashland, or 8
  miles northwest of Wilmington, moving northeast at 25 mph.

  HAZARD...60 mph wind gusts and nickel size hail.

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Philadelphia, Wilmington, Chester, Yeadon, Westtown, Conshohocken,
  Folcroft, Swarthmore, Elsmere, Paulsboro, Kennett Square,
  Westville, Narberth, National Park, East Lansdowne, Brooklawn,
  Arden, Darby Township, Cheyney and Morris Park.

This includes the following highways...
 Interstate 95 in Pennsylvania between mile markers 0 and 19.
 Interstate 95 in Delaware between mile markers 15 and 23.
 Interstate 76 in Pennsylvania between mile markers 331 and 339, and
between mile markers 341 and 351.
 Interstate 676 in Pennsylvania near mile marker 0.
 Interstate 476 in Pennsylvania between mile markers 0 and 18.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 700 PM EDT for northern
Delaware...southern New Jersey...and southeastern Pennsylvania.

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

To report severe weather, contact your nearest law enforcement
agency. They will send your report to the National Weather Service
office in Mount Holly NJ.

A Tornado Watch remains in effect until 700 PM EDT for northern
Delaware...southern New Jersey...and southeastern Pennsylvania.

&&

LAT...LON 4011 7527 3990 7513 3989 7514 3987 7512
      3987 7513 3972 7566 3986 7577
TIME...MOT...LOC 1827Z 242DEG 23KT 3982 7564 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.88 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

MPS
2 follow-up statements
824 
WWUS51 KPHI 201846
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
246 PM EDT Fri May 20 2022

PAC029-091-201855-
/O.CAN.KPHI.SV.W.0037.000000T0000Z-220520T1915Z/
Montgomery PA-Chester PA-
246 PM EDT Fri May 20 2022

...THE SEVERE THUNDERSTORM WARNING FOR SOUTH CENTRAL MONTGOMERY AND
SOUTHEASTERN CHESTER COUNTIES IS CANCELLED...
    
The severe thunderstorm which prompted the warning has moved out of 
the warned area. Therefore, the warning has been cancelled.

A Tornado Watch remains in effect until 700 PM EDT for northern
Delaware...southern New Jersey...and southeastern Pennsylvania.

LAT...LON 3976 7552 3992 7552 3994 7516 3990 7513
      3989 7514 3987 7512 3987 7513
TIME...MOT...LOC 1845Z 271DEG 32KT 3983 7543 

$$

DEC003-NJC015-PAC045-101-201915-
/O.CON.KPHI.SV.W.0037.000000T0000Z-220520T1915Z/
New Castle DE-Gloucester NJ-Philadelphia PA-Delaware PA-
246 PM EDT Fri May 20 2022

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 315 PM EDT
FOR NORTHEASTERN NEW CASTLE...NORTHWESTERN GLOUCESTER...SOUTHWESTERN
PHILADELPHIA AND SOUTHERN DELAWARE COUNTIES...

At 245 PM EDT, a severe thunderstorm was located over Chester
Township, or 8 miles northeast of Wilmington, moving east at 35 mph.

HAZARD...60 mph wind gusts and nickel size hail.

SOURCE...Radar indicated.

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

Locations impacted include...
Philadelphia, Chester, Yeadon, Folcroft, Swarthmore, Paulsboro,
Westville, National Park, Brooklawn, Arden, Darby Township, Chelsea,
Chester Township, Tinicum Township, Lima, South Philadelphia, Nether
Providence Township, Philadelphia International Arpt, Philadelphia
International Airport and Concordville.

This includes the following highways...
 Interstate 95 in Pennsylvania between mile markers 0 and 19.
 Interstate 95 in Delaware between mile markers 18 and 23.
 Interstate 76 in Pennsylvania between mile markers 346 and 351.
 Interstate 476 in Pennsylvania between mile markers 0 and 4.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 700 PM EDT for northern
Delaware...southern New Jersey...and southeastern Pennsylvania.

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

To report severe weather contact your nearest law enforcement agency.
They will send your report to the National Weather Service office in
Mount Holly NJ.

&&

LAT...LON 3976 7552 3992 7552 3994 7516 3990 7513
      3989 7514 3987 7512 3987 7513
TIME...MOT...LOC 1845Z 271DEG 32KT 3983 7543 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.88 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

MPS
567 
WWUS51 KPHI 201908
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
308 PM EDT Fri May 20 2022

DEC003-NJC015-PAC045-101-201917-
/O.EXP.KPHI.SV.W.0037.000000T0000Z-220520T1915Z/
New Castle DE-Gloucester NJ-Philadelphia PA-Delaware PA-
308 PM EDT Fri May 20 2022

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN NEW CASTLE...
NORTHWESTERN GLOUCESTER...SOUTHWESTERN PHILADELPHIA AND SOUTHERN
DELAWARE COUNTIES WILL EXPIRE AT 315 PM EDT...
        
The storm which prompted the warning has moved out of the area.
Therefore, the warning will be allowed to expire.  However small hail
and gusty winds are still possible with this thunderstorm.

A Tornado Watch remains in effect until 700 PM EDT for northern
Delaware...southern New Jersey...and southeastern Pennsylvania.

To report severe weather, contact your nearest law enforcement
agency. They will relay your report to the National Weather Service
Mount Holly NJ.

Remember, a Severe Thunderstorm Warning still remains in effect for 
portions of Gloucester, Philadelphia, and Delaware counties.

LAT...LON 3976 7552 3992 7552 3994 7516 3990 7513
      3989 7514 3987 7512 3987 7513
TIME...MOT...LOC 1907Z 242DEG 23KT 3989 7528 

$$

MPS

The office that day

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

IssuedProductOfficeCountiesLasted
May 20, 3:15 AM EDTHeat AdvisoryPHIBucks, Chester, Delaware, Montgomery, Philadelphia59 hr
May 20, 1:45 PM EDTSevere Thunderstorm WarningPHIBerks, Chester, Montgomery45 min
May 20, 2:22 PM EDTSevere Thunderstorm WarningPHIBerks, Bucks, Chester, Lehigh, Montgomery53 min
May 20, 2:30 PM EDTSevere Thunderstorm WarningPHIBerks45 min
May 20, 2:53 PM EDTSevere Thunderstorm WarningPHIBerks, Lehigh, Montgomery52 min
May 20, 3:00 PM EDTSevere Thunderstorm WarningPHIDelaware, Philadelphia31 min
May 20, 3:05 PM EDTSevere Thunderstorm WarningPHIBucks, Montgomery29 min
May 20, 3:10 PM EDTSevere Thunderstorm WarningPHIBerks, Bucks, Chester, Lehigh, Montgomery50 min
May 20, 3:25 PM EDTSevere Thunderstorm WarningPHIBerks, Carbon, Lehigh, Monroe, Northampton50 min
May 20, 3:28 PM EDTSpecial Weather StatementPHIPhiladelphia32 min
May 20, 3:37 PM EDTSevere Thunderstorm WarningPHIBucks, Chester, Delaware, Montgomery, Philadelphia53 min
May 20, 3:41 PM EDTSevere Thunderstorm Warning Considerable damage threatPHIBucks, Lehigh, Montgomery, Northampton49 min
May 20, 3:52 PM EDTAreal Flood AdvisoryPHIBucks, Chester, Delaware, Lehigh, Montgomery, Philadelphia3 hr
May 20, 3:55 PM EDTAreal Flood AdvisoryPHIBerks, Bucks, Carbon, Chester, Lehigh, Monroe and 2 more3 hr
May 20, 4:26 PM EDTAreal Flood AdvisoryPHIBucks, Philadelphia3 hr
May 20, 5:37 PM EDTAreal Flood WarningPHIBucks, Montgomery68 min
May 20, 12:30 PM EDTMarine Dense Fog AdvisoryPHI6 hr
May 20, 3:48 PM EDTSpecial Weather StatementPHIMonmouth27 min
May 20, 4:11 PM EDTSpecial Weather StatementPHISussex34 min
May 20, 4:32 PM EDTSpecial Weather StatementPHIMercer, Middlesex28 min
May 20, 4:33 PM EDTSevere Thunderstorm WarningPHIBurlington, Camden, Ocean42 min
May 20, 4:56 PM EDTSpecial Weather StatementPHIMiddlesex, Monmouth49 min
May 20, 5:11 PM EDTSevere Thunderstorm Warning Considerable damage threatPHIBurlington, Camden, Ocean64 min
May 20, 5:15 PM EDTSpecial Marine WarningPHI45 min
May 20, 5:20 PM EDTSevere Thunderstorm WarningPHIMonmouth, Ocean27 min
May 20, 5:51 PM EDTSpecial Marine WarningPHI32 min
May 20, 5:54 PM EDTSevere Thunderstorm WarningPHIOcean28 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2022Severe Thunderstorm Warnings in New Jersey, 2022Severe Thunderstorm Warnings in Delaware, 2022Every severe thunderstorm 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.