Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 65, NWS Philadelphia/Mount Holly

June 4, 20204 counties in Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jun 4, 2020, 6:42 PM EDT for 4 counties in Pennsylvania. It was in force for 63 min. 1 report 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 4, 2020, 6:42 PM EDT (22:42 UTC)
Expired: Jun 4, 2020, 7:45 PM EDT
In force: 63 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

The radar

The Philadelphia radar (KDIX), 119 km from the middle of the area, began a volume at 22:42 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

Time	Report	Where	Remark
Jun 4, 7:00 PM EDT	TSTM WND GST 58	1 Ssw Ruscombmanor Twp, PA	CWOP SITE.

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 12:00Z, 10.7 hours before the alert went out and 228 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: 1 J/kg
Mixed-layer CIN: -104 J/kg
Mixed-layer LCL: 1402 m above ground
0-6 km bulk shear: 47 kt
0-1 km storm-relative helicity: 17 m²/s²
0-3 km storm-relative helicity: 81 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

233 
WUUS51 KPHI 042242
SVRPHI
PAC011-017-077-091-042345-
/O.NEW.KPHI.SV.W.0065.200604T2242Z-200604T2345Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
642 PM EDT Thu Jun 4 2020

The National Weather Service in Mount Holly NJ has issued a

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

* Until 745 PM EDT.

* At 641 PM EDT, a severe thunderstorm was located over Leesport, or
  7 miles north of Reading, moving east at 30 mph.

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

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Allentown, Reading, Bethlehem, Emmaus, Wyomissing, Northampton,
  Quakertown, Kutztown, Hamburg, Fleetwood, Sinking Spring,
  Laureldale, East Greenville, Topton, Leesport, Shoemakersville,
  Bally, Bechtelsville, Green Lane and Lyons.

This includes the following highways...
 Interstate 78 in Pennsylvania between mile markers 27 and 63.
 Northeast Extension between exits A44 and A56.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Protecting yourself from immediate threats to life and safety shall
take priority.  Whenever possible, as long as it does not cause
greater harm, all COVID-19 protective action guidance should be
followed.

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 4069 7550 4066 7548 4067 7543 4062 7538
      4058 7541 4054 7534 4034 7531 4033 7605
      4055 7607
TIME...MOT...LOC 2241Z 258DEG 27KT 4045 7594 

HAIL...0.75IN
WIND...60MPH
 
$$

Gorse

3 follow-up statements

605 
WWUS51 KPHI 042302
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
702 PM EDT Thu Jun 4 2020

PAC011-017-077-091-042345-
/O.CON.KPHI.SV.W.0065.000000T0000Z-200604T2345Z/
Berks PA-Lehigh PA-Montgomery PA-Bucks PA-
702 PM EDT Thu Jun 4 2020

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 745 PM EDT
FOR NORTHEASTERN BERKS...LEHIGH...NORTHWESTERN MONTGOMERY AND
NORTHWESTERN BUCKS COUNTIES...

At 702 PM EDT, a severe thunderstorm was located over Lyons, or 14
miles northeast of Reading, moving east at 30 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

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

Locations impacted include...
Allentown, Bethlehem, Emmaus, Northampton, Quakertown, Kutztown,
Fleetwood, Laureldale, East Greenville, Topton, Bally, Bechtelsville,
Lyons, Lenhartsville, Coffeetown, Zionsville, Ancient Oaks,
Claussville, Geryville and Catasauqua.

This includes the following highways...
 Interstate 78 in Pennsylvania between mile markers 33 and 63.
 Northeast Extension between exits A44 and A56.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Protecting yourself from immediate threats to life and safety shall
take priority.  Whenever possible, as long as it does not cause
greater harm, all COVID-19 protective action guidance should be
followed.

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

Frequent 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 4069 7550 4066 7548 4067 7543 4062 7538
      4058 7541 4054 7534 4034 7531 4037 7594
      4057 7597
TIME...MOT...LOC 2302Z 258DEG 27KT 4048 7573 

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

Gorse

166 
WWUS51 KPHI 042318
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
718 PM EDT Thu Jun 4 2020

PAC011-017-077-091-042345-
/O.CON.KPHI.SV.W.0065.000000T0000Z-200604T2345Z/
Berks PA-Lehigh PA-Montgomery PA-Bucks PA-
718 PM EDT Thu Jun 4 2020

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 745 PM EDT
FOR NORTHEASTERN BERKS...LEHIGH...NORTHWESTERN MONTGOMERY AND
NORTHWESTERN BUCKS COUNTIES...

At 717 PM EDT, a severe thunderstorm was located near Ancient Oaks, 
or 10 miles southwest of Allentown, moving east at 30 mph. The 
intensity of this storm however is trending downward. 

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

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

Locations impacted include...
Allentown, Bethlehem, Emmaus, Northampton, Quakertown, East
Greenville, Topton, Bally, Bechtelsville, Coffeetown, Zionsville,
Ancient Oaks, Claussville, Geryville, Catasauqua, Fountain Hill,
Sellersville, Pennsburg, Coplay and Macungie.

This includes the following highways...
 Interstate 78 in Pennsylvania between mile markers 45 and 63.
 Northeast Extension between exits A44 and A56.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Protecting yourself from immediate threats to life and safety shall
take priority.  Whenever possible, as long as it does not cause
greater harm, all COVID-19 protective action guidance should be
followed.

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

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 4069 7550 4066 7548 4067 7543 4062 7538
      4058 7541 4054 7534 4034 7531 4036 7574
      4060 7575
TIME...MOT...LOC 2317Z 261DEG 24KT 4048 7562 

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

Gorse

133 
WWUS51 KPHI 042343
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
743 PM EDT Thu Jun 4 2020

PAC011-017-077-091-042352-
/O.EXP.KPHI.SV.W.0065.000000T0000Z-200604T2345Z/
Berks PA-Lehigh PA-Montgomery PA-Bucks PA-
743 PM EDT Thu Jun 4 2020

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN BERKS...LEHIGH...
NORTHWESTERN MONTGOMERY AND NORTHWESTERN BUCKS COUNTIES WILL EXPIRE
AT 745 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 are still possible with this thunderstorm.

LAT...LON 4069 7550 4066 7548 4067 7543 4062 7538
      4058 7541 4054 7534 4034 7531 4036 7574
      4060 7575
TIME...MOT...LOC 2342Z 258DEG 27KT 4052 7539 

$$

Gorse

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 3, 8:52 PM EDT	Severe Thunderstorm Warning	PHI	Chester	24 min
Jun 4, 6:06 AM EDT	Coastal Flood Advisory	PHI	Bucks, Delaware, Philadelphia	22 hr
Jun 4, 5:39 PM EDT	Severe Thunderstorm Warning	PHI	Berks	81 min
Jun 4, 7:47 PM EDT	Special Weather Statement	PHI	Bucks	43 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2020 Every severe thunderstorm warning in 2020

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.