Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 164, NWS Philadelphia/Mount Holly

August 5, 2012Berks County, Chester County, Montgomery County, Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Aug 5, 2012, 4:23 PM EDT for Berks County, Chester County, Montgomery County, Pennsylvania. It was in force for 67 min. 2 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: Aug 5, 2012, 4:23 PM EDT (20:23 UTC)
Expired: Aug 5, 2012, 5:30 PM EDT
In force: 67 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon

Counties Berks County, PA, Chester County, PA, Montgomery County, PA

The radar

The Philadelphia radar (KDIX), 141 km from the middle of the area, began a volume at 20:26 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
Aug 5, 4:59 PM EDT	TSTM WND GST 51	Reading Airport, PA	51 MPH WIND GUST AT READING AIRPORT.
Aug 5, 5:13 PM EDT	TSTM WND DMG	Reading, PA	LARGE BRANCHES BROKEN IN READING.

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
Aug 5, 3:36 PM EDT	Severe Thunderstorm Watch	SPC	5 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 8.4 hours before the alert went out and 173 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: 809 J/kg
Mixed-layer CIN: -82 J/kg
Mixed-layer LCL: 1048 m above ground
0-6 km bulk shear: 5 kt
0-1 km storm-relative helicity: 48 m²/s²
0-3 km storm-relative helicity: 57 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

768 
WUUS51 KPHI 052023
SVRPHI
PAC011-029-091-052130-
/O.NEW.KPHI.SV.W.0164.120805T2023Z-120805T2130Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
423 PM EDT SUN AUG 5 2012

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHERN BERKS COUNTY IN EASTERN PENNSYLVANIA...
  THIS INCLUDES THE CITY OF READING...
  WESTERN CHESTER COUNTY IN SOUTHEAST PENNSYLVANIA...
  NORTHWESTERN MONTGOMERY COUNTY IN SOUTHEAST PENNSYLVANIA...

* UNTIL 530 PM EDT

* AT 417 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING QUARTER SIZE
  HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH.  THESE STORMS WERE
  LOCATED ALONG A LINE EXTENDING FROM NEAR LEBANON TO ELIZABTHTOWN TO
  YORK...AND MOVING EAST AT 30 MPH.

* SEVERE THUNDERSTORMS WILL BE NEAR...
  WOMELSDORF AROUND 445 PM EDT...
  BERNVILLE AROUND 450 PM EDT...
  WERNERSVILLE AROUND 500 PM EDT...
  LEESPORT AND SINKING SPRING AROUND 505 PM EDT...
  LAURELDALE AND WYOMISSING AROUND 510 PM EDT...
  READING AROUND 515 PM EDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS A DANGEROUS STORM. IF YOU ARE IN ITS PATH...PREPARE
IMMEDIATELY FOR DAMAGING WINDS...LARGE HAIL...AND DEADLY CLOUD TO
GROUND LIGHTNING. PEOPLE OUTSIDE SHOULD MOVE TO A SHELTER...
PREFERABLY INSIDE A STRONG BUILDING BUT AWAY FROM WINDOWS.

PLEASE REPORT HAIL OR STRONG WINDS TO THE NATIONAL WEATHER SERVICE BY
CALLING TOLL FREE...1-877-633-6772...WHEN YOU CAN DO SO SAFELY.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 900 PM EDT SUNDAY
EVENING FOR EASTERN PENNSYLVANIA.

&&

LAT...LON 4049 7643 4050 7637 4042 7555 3973 7585
      3972 7614 3974 7610 3988 7600 3998 7599
      4003 7594 4011 7595 4014 7589
TIME...MOT...LOC 2022Z 271DEG 24KT 4043 7634 3971 7677

$$

IOVINO

1 follow-up statement

183 
WWUS51 KPHI 052102
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
502 PM EDT SUN AUG 5 2012

PAC011-029-091-052130-
/O.CON.KPHI.SV.W.0164.000000T0000Z-120805T2130Z/
BERKS PA-MONTGOMERY PA-CHESTER PA-
502 PM EDT SUN AUG 5 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 530 PM EDT
FOR WESTERN CHESTER...NORTHWESTERN MONTGOMERY AND SOUTHERN BERKS
COUNTIES...

AT 500 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING QUARTER
SIZE HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH.  THESE STORMS 
WERE LOCATED ALONG A LINE EXTENDING FROM LEESPORT TO EPHRATA TO 
LANCASTER...MOVING EAST AT 30 MPH.

SEVERE THUNDERSTORMS WILL BE NEAR...
  WYOMISSING HILLS...WYOMISSING...WEST WYOMISSING AND WEST LAWN BY
  510 PM EDT...
  WEST READING...SHILLINGTON...READING AND LAURELDALE BY 515 PM
  EDT...
  MOUNT PENN AND FLYING HILLS BY 520 PM EDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS A DANGEROUS STORM. IF YOU ARE IN ITS PATH...PREPARE
IMMEDIATELY FOR DAMAGING WINDS...DESTRUCTIVE HAIL...AND DEADLY CLOUD
TO GROUND LIGHTNING. PEOPLE OUTSIDE SHOULD MOVE TO A SHELTER...
PREFERABLY INSIDE A STRONG BUILDING BUT AWAY FROM WINDOWS.

PLEASE REPORT HAIL OR STRONG WINDS TO THE NATIONAL WEATHER SERVICE BY
CALLING TOLL FREE...1-877-633-6772...WHEN YOU CAN DO SO SAFELY.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 900 PM EDT SUNDAY
EVENING FOR NORTHERN DELAWARE AND NORTHEASTERN MARYLAND AND NEW
JERSEY AND EASTERN PENNSYLVANIA.

&&

LAT...LON 4049 7643 4050 7637 4042 7555 3973 7585
      3972 7614 3974 7610 3988 7600 3998 7599
      4003 7594 4011 7595 4014 7589
TIME...MOT...LOC 2101Z 271DEG 24KT 4042 7600 3971 7643

$$

IOVINO

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 5, 3:49 AM EDT	Flash Flood Watch	PHI	Carbon, Monroe, Northampton	16 hr
Aug 5, 12:15 PM EDT	Special Weather Statement	PHI	Carbon, Monroe	45 min
Aug 5, 12:29 PM EDT	Special Weather Statement	PHI	Northampton	31 min
Aug 5, 1:03 PM EDT	Special Weather Statement	PHI	Monroe	27 min
Aug 5, 4:12 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Carbon, Lehigh, Monroe, Northampton	78 min
Aug 5, 5:13 PM EDT	Severe Thunderstorm Warning	PHI	Monroe, Northampton	77 min
Aug 5, 5:22 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Bucks, Chester, Delaware, Lehigh, Montgomery and 2 more	68 min
Aug 5, 6:16 PM EDT	Severe Thunderstorm Warning	PHI	Bucks, Delaware, Montgomery, Philadelphia	74 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2012 Every severe thunderstorm warning in 2012

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.