Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 51, NWS Philadelphia/Mount Holly

June 4, 2021Berks County, Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jun 4, 2021, 2:27 PM EDT for Berks County, Pennsylvania. It was in force for 48 min. 3 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 4, 2021, 2:27 PM EDT (18:27 UTC)
Expired: Jun 4, 2021, 3:15 PM EDT
In force: 48 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

County Berks County, PA

The radar

The Philadelphia radar (KDIX), 153 km from the middle of the area, began a volume at 18:27 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, 2:54 PM EDT	TSTM WND DMG	1 N West Lawn, PA	DOWNED UTILITY ON STATE HILL ROAD NEAR KEISER BOULEVARD. TIME ESTIMATED FROM RADAR.
Jun 4, 3:05 PM EDT	TSTM WND DMG	1 Sw Kenhorst, PA	DOWNED TREES OR LIMBS CAUSED A POWER OUTAGE NEAR HARDING AVE. TIME ESTIMATED FROM RADAR.
Jun 4, 3:12 PM EDT	TSTM WND DMG	1 W Sinking Spring, PA	TREE LIMBS DOWN ON WIRES NEAR RUTH ST. 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

Washington/Dulle, VA (KIAD), launched 12:00Z, 6.5 hours before the alert went out and 196 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: 381 J/kg
Mixed-layer CIN: -55 J/kg
Mixed-layer LCL: 947 m above ground
0-6 km bulk shear: 42 kt
0-1 km storm-relative helicity: -8 m²/s²
0-3 km storm-relative helicity: 73 m²/s²
Significant tornado parameter: -0.0
Supercell composite: -0.1

Open this sounding in Storm Lab

The text

As transmitted.

127 
WUUS51 KPHI 041827
SVRPHI
PAC011-041915-
/O.NEW.KPHI.SV.W.0051.210604T1827Z-210604T1915Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
227 PM EDT Fri Jun 4 2021

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Central Berks County in eastern Pennsylvania...

* Until 315 PM EDT.

* At 227 PM EDT, a severe thunderstorm was located over Bernville, or
  10 miles northeast of Myerstown, moving east at 20 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...
  Reading, Wyomissing, Kutztown, Fleetwood, Sinking Spring,
  Laureldale, Womelsdorf, Wernersville, Robesonia, Leesport,
  Shoemakersville, Bernville, Lyons, Strausstown, New Morgan, Spring
  Ridge, Fairview Hgts, Shillington, West Reading and Mount Penn.

This includes Interstate 176 in Pennsylvania between mile markers 4
and 11.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

&&

LAT...LON 4048 7624 4054 7602 4053 7570 4018 7589
      4032 7616 4036 7621 4037 7623 4039 7628
TIME...MOT...LOC 1827Z 271DEG 19KT 4043 7613 

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

Davis

2 follow-up statements

237 
WWUS51 KPHI 041856
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
256 PM EDT Fri Jun 4 2021

PAC011-041915-
/O.CON.KPHI.SV.W.0051.000000T0000Z-210604T1915Z/
Berks PA-
256 PM EDT Fri Jun 4 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 315 PM EDT
FOR CENTRAL BERKS COUNTY...

At 256 PM EDT, a severe thunderstorm was located over Wyomissing, or
over Reading, moving east at 25 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

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

Locations impacted include...
Reading, Wyomissing, Sinking Spring, Laureldale, Womelsdorf,
Wernersville, Robesonia, Bernville, New Morgan, Fairview Hgts, Spring
Ridge, Shillington, West Reading, Mount Penn, Mohnton, Kenhorst, St.
Lawrence, Wyomissing Hills, West Lawn and Lorane.

This includes Interstate 176 in Pennsylvania between mile markers 4
and 11.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

&&

LAT...LON 4038 7625 4046 7608 4039 7578 4018 7590
      4032 7616 4036 7621
TIME...MOT...LOC 1856Z 284DEG 21KT 4033 7596 

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

JEO

348 
WWUS51 KPHI 041916
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
316 PM EDT Fri Jun 4 2021

PAC011-041926-
/O.EXP.KPHI.SV.W.0051.000000T0000Z-210604T1915Z/
Berks PA-
316 PM EDT Fri Jun 4 2021

...THE SEVERE THUNDERSTORM WARNING FOR CENTRAL BERKS COUNTY HAS
EXPIRED...
                
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 has been allowed to expire. However gusty 
winds are still possible with this thunderstorm.

LAT...LON 4038 7625 4046 7608 4039 7578 4018 7590
      4032 7616 4036 7621
TIME...MOT...LOC 1916Z 271DEG 19KT 4015 7528 

$$

JEO

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 3, 8:44 PM EDT	Severe Thunderstorm Warning	PHI	Bucks	30 min
Jun 4, 1:02 PM EDT	Special Weather Statement	PHI	Lehigh	28 min
Jun 4, 1:07 PM EDT	Special Weather Statement	PHI	Carbon, Monroe	38 min
Jun 4, 1:29 PM EDT	Areal Flood Advisory	PHI	Berks, Lehigh	2 hr
Jun 4, 1:45 PM EDT	Areal Flood Advisory	PHI	Monroe, Northampton	97 min
Jun 4, 1:49 PM EDT	Severe Thunderstorm Warning	PHI	Monroe, Northampton	41 min
Jun 4, 2:21 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Bucks, Lehigh, Montgomery	21 min
Jun 4, 2:24 PM EDT	Severe Thunderstorm Warning	PHI	Bucks, Montgomery	51 min
Jun 4, 3:14 PM EDT	Severe Thunderstorm Warning	PHI	Bucks, Montgomery, Philadelphia	46 min
Jun 4, 3:16 PM EDT	Areal Flood Advisory	PHI	Bucks, Chester, Delaware, Montgomery, Philadelphia	98 min
Jun 4, 3:18 PM EDT	Severe Thunderstorm Warning	PHI	Bucks	42 min
Jun 4, 3:23 PM EDT	Severe Thunderstorm Warning	PHI	Bucks	67 min
Jun 4, 3:46 PM EDT	Severe Thunderstorm Warning	PHI	Bucks, Philadelphia	44 min
Jun 4, 4:20 PM EDT	Severe Thunderstorm Warning	PHI	Philadelphia	40 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2021 Every severe thunderstorm 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.