Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2017

Severe Thunderstorm Warning 69, NWS Philadelphia/Mount Holly

June 23, 20174 counties in Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jun 23, 2017, 5:21 PM EDT for 4 counties in Pennsylvania. It was in force for 54 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 23, 2017, 5:21 PM EDT (21:21 UTC)
Expired: Jun 23, 2017, 6:15 PM EDT
In force: 54 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), 121 km from the middle of the area, began a volume at 21:22 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 23, 5:27 PM EDT	TSTM WND DMG	Upper Saucon Twp, PA	TREE REPORTED DOWN AT THE TUMBLEBROOK GOLF COURSE.

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.

Issued	Product	Office	Lasted
Jun 23, 5:09 PM EDT	Severe Thunderstorm Watch	SPC	4 hr

The nearest sounding before it

Brookhaven, NY (KOKX), launched 12:00Z, 9.4 hours before the alert went out and 233 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: 688 J/kg
Mixed-layer CIN: -89 J/kg
Mixed-layer LCL: 1159 m above ground
0-6 km bulk shear: 29 kt
0-1 km storm-relative helicity: 83 m²/s²
0-3 km storm-relative helicity: 100 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 0.6

Open this sounding in Storm Lab

The text

As transmitted.

125 
WUUS51 KPHI 232121
SVRPHI
PAC011-017-077-091-232215-
/O.NEW.KPHI.SV.W.0069.170623T2121Z-170623T2215Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
521 PM EDT FRI JUN 23 2017

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...
  Southeastern Lehigh County in eastern Pennsylvania...
  West central Bucks County in southeastern Pennsylvania...

* Until 615 PM EDT

* At 520 PM EDT, a severe thunderstorm was located near Leesport, or 
  9 miles north of Reading, moving east at 30 mph. Some rotation has 
  been indicated by radar inside this storm. While not likely, a 
  tornado is possible.

  HAZARD...60 mph wind gusts. 

  SOURCE...Radar indicated. 

  IMPACT...Expect damage to trees and power lines. 

* Locations impacted include...
  Allentown, Reading, Bethlehem, Emmaus, Quakertown, Kutztown,
  Hamburg, Fleetwood, Laureldale, East Greenville, Topton, Leesport,
  Shoemakersville, Bally, Lyons, Zionsville, Ancient Oaks,
  Claussville, Geryville and Catasauqua.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4053 7604 4067 7542 4064 7539 4061 7538
      4058 7541 4056 7537 4042 7533 4036 7598
TIME...MOT...LOC 2120Z 256DEG 27KT 4047 7591 

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

Meola

1 follow-up statement

420 
WWUS51 KPHI 232156
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
556 PM EDT FRI JUN 23 2017

PAC011-017-077-091-232215-
/O.CON.KPHI.SV.W.0069.000000T0000Z-170623T2215Z/
Berks PA-Montgomery PA-Lehigh PA-Bucks PA-
556 PM EDT FRI JUN 23 2017

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 615 PM EDT
FOR NORTHEASTERN BERKS...NORTHWESTERN MONTGOMERY...SOUTHEASTERN
LEHIGH AND WEST CENTRAL BUCKS COUNTIES...

At 555 PM EDT, a severe thunderstorm was located near Topton, or 12 
miles southwest of Allentown, moving east at 25 mph. Some rotation 
has been indicated by radar inside this storm. While not likely, a 
tornado is possible.

HAZARD...60 mph wind gusts. 

SOURCE...Radar indicated. 

IMPACT...Expect damage to trees and power lines. 

Locations impacted include...
Allentown, Bethlehem, Emmaus, Quakertown, Kutztown, Fleetwood,
Laureldale, East Greenville, Topton, Bally, Lyons, Zionsville,
Geryville, Ancient Oaks, Catasauqua, Fountain Hill, Macungie,
Coopersburg, Alburtis and Trumbauersville.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

In addition to 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 4054 7583 4063 7559 4067 7542 4064 7539
      4061 7538 4058 7541 4056 7537 4042 7533
      4037 7592
TIME...MOT...LOC 2155Z 258DEG 23KT 4046 7565 

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

Meola

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 23, 4:53 PM EDT	Special Weather Statement	PHI	Berks	52 min
Jun 23, 5:15 PM EDT	Areal Flood Advisory	PHI	Berks, Carbon, Lehigh, Northampton	4 hr
Jun 23, 5:33 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Bucks, Chester, Montgomery	57 min
Jun 23, 6:10 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Bucks, Lehigh, Montgomery	50 min
Jun 23, 6:57 PM EDT	Special Weather Statement	PHI	Bucks	33 min
Jun 23, 6:58 PM EDT	Areal Flood Advisory	PHI	Bucks, Lehigh, Northampton	4 hr
Jun 23, 7:30 PM EDT	Areal Flood Advisory	PHI	Bucks, Montgomery	4 hr
Jun 23, 7:46 PM EDT	Special Weather Statement	PHI	Berks, Carbon, Lehigh, Northampton	59 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2017 Every severe thunderstorm warning in 2017

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.