Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2019

Severe Thunderstorm Warning 46, NWS Philadelphia/Mount Holly

May 23, 2019Berks County, Chester County, Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at May 23, 2019, 10:47 PM EDT for Berks County, Chester County, Pennsylvania. It was in force for 43 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: May 23, 2019, 10:47 PM EDT (02:47 UTC)
Expired: May 23, 2019, 11:30 PM EDT
In force: 43 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Tornado: Possible
Hail: 1.0 in
Wind: 60.0 mph

Counties Berks County, PA, Chester County, PA

The radar

The Philadelphia radar (KDIX), 129 km from the middle of the area, began a volume at 02:50 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.

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 00:00Z, 2.8 hours before the alert went out and 182 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 225 J/kg
Mixed-layer CIN: -114 J/kg
Mixed-layer LCL: 1497 m above ground
0-6 km bulk shear: 51 kt
0-1 km storm-relative helicity: 192 m²/s²
0-3 km storm-relative helicity: 267 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 2.3

Open this sounding in Storm Lab

The text

As transmitted.

486 
WUUS51 KPHI 240247
SVRPHI
PAC011-029-240330-
/O.NEW.KPHI.SV.W.0046.190524T0247Z-190524T0330Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
1047 PM EDT Thu May 23 2019

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  South central Berks County in eastern Pennsylvania...
  Chester County in southeastern Pennsylvania...

* Until 1130 PM EDT.

* At 1047 PM EDT, a severe thunderstorm was located over Terre Hill,
  or near Ephrata, moving southeast at 45 mph.

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

  SOURCE...Radar indicated.

  IMPACT...Minor damage to vehicles is possible. Wind damage to 
           roofs, siding, trees, and power lines is possible.

* Locations impacted include...
  West Chester, Coatesville, Downingtown, Kennett Square, Parkesburg,
  Honey Brook, Elverson, New Morgan, Marshallton,
  Lionville-Marchwood, Glenmoore, Paoli, Chester Springs, Lionville,
  West Goshen, Malvern, Atglen, South Coatesville, Avondale and
  Modena.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Remain alert for a possible tornado! Tornadoes can develop quickly
from severe thunderstorms. If you spot a tornado go at once into the
basement or small central room in a sturdy structure.

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.

&&

LAT...LON 4032 7610 4006 7540 3977 7575 3996 7599
      4004 7593 4011 7594 4014 7588 4031 7614
TIME...MOT...LOC 0247Z 302DEG 41KT 4017 7609 

TORNADO...POSSIBLE
HAIL...1.00IN
WIND...60MPH
 
$$

Robertson

2 follow-up statements

986 
WWUS51 KPHI 240313
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
1113 PM EDT Thu May 23 2019

PAC011-240322-
/O.CAN.KPHI.SV.W.0046.000000T0000Z-190524T0330Z/
Berks PA-
1113 PM EDT Thu May 23 2019

...THE SEVERE THUNDERSTORM WARNING FOR SOUTH CENTRAL BERKS COUNTY IS
CANCELLED...
    
The severe thunderstorm which prompted the warning has moved out of 
the warned area. Therefore, the warning has been cancelled.

LAT...LON 4004 7593 4011 7594 4013 7590 4014 7587
      4020 7577 4006 7540 3977 7575 3996 7599
TIME...MOT...LOC 0312Z 302DEG 41KT 4002 7577 

$$

PAC029-240330-
/O.CON.KPHI.SV.W.0046.000000T0000Z-190524T0330Z/
Chester PA-
1113 PM EDT Thu May 23 2019

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1130 PM EDT
FOR CHESTER COUNTY...

At 1112 PM EDT, a severe thunderstorm was located near Coatesville,
or 9 miles northwest of West Chester, moving southeast at 45 mph.

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

SOURCE...Radar indicated.

IMPACT...Minor damage to vehicles is possible. Wind damage to roofs, 
         siding, trees, and power lines is possible.

Locations impacted include...
West Chester, Coatesville, Downingtown, Kennett Square, Parkesburg,
Honey Brook, Elverson, Glenmoore, Paoli, Chester Springs, Lionville,
Marshallton, Lionville-Marchwood, West Goshen, Malvern, Atglen, South
Coatesville, Avondale, Modena and Exton.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Remain alert for a possible tornado! A tornado warning is also in 
effect for a portion of the area. Tornadoes can develop quickly 
from severe thunderstorms. If you spot a tornado go at once into the 
basement or small central room in a sturdy structure.

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.

&&

LAT...LON 4004 7593 4011 7594 4013 7590 4014 7587
      4020 7577 4006 7540 3977 7575 3996 7599
TIME...MOT...LOC 0312Z 302DEG 41KT 4002 7577 

TORNADO...POSSIBLE
HAIL...1.00IN
WIND...60MPH
 
$$

Robertson

742 
WWUS51 KPHI 240327
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
1127 PM EDT Thu May 23 2019

PAC029-240337-
/O.EXP.KPHI.SV.W.0046.000000T0000Z-190524T0330Z/
Chester PA-
1127 PM EDT Thu May 23 2019

...THE SEVERE THUNDERSTORM WARNING FOR CHESTER COUNTY WILL EXPIRE AT
1130 PM EDT...
        
The storm which prompted the warning has moved out of the area.
Therefore, the warning will be allowed to expire.

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

LAT...LON 4004 7593 4011 7594 4013 7590 4014 7587
      4020 7577 4006 7540 3977 7575 3996 7599
TIME...MOT...LOC 0327Z 302DEG 41KT 3994 7561 

$$

MPS

The office that day

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

Issued	Product	Office	Counties	Lasted
May 23, 9:28 PM EDT	Special Weather Statement	PHI	Carbon, Monroe	32 min
May 23, 9:37 PM EDT	Severe Thunderstorm Warning	PHI	Carbon, Monroe	23 min
May 23, 9:50 PM EDT	Tornado Warning	PHI	Carbon, Monroe	25 min
May 23, 9:59 PM EDT	Tornado Warning	PHI	Monroe, Northampton	31 min
May 23, 11:01 PM EDT	Tornado Warning	PHI	Chester	29 min
May 23, 11:22 PM EDT	Severe Thunderstorm Warning	PHI	Chester, Delaware, Montgomery, Philadelphia	38 min
May 23, 11:37 PM EDT	Special Weather Statement	PHI	Berks	38 min
May 24, 12:15 AM EDT	Special Weather Statement	PHI	Montgomery, Philadelphia	30 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2019 Every 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.