Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2016

Severe Thunderstorm Warning 24, NWS Philadelphia/Mount Holly

April 7, 2016Chester County, Delaware County, Pennsylvania; Cecil County, Maryland; New Castle County, Delaware

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Apr 7, 2016, 12:08 PM EDT for Chester County, Delaware County, Pennsylvania; Cecil County, Maryland; New Castle County, Delaware. It was in force for 37 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: Apr 7, 2016, 12:08 PM EDT (16:08 UTC)
Expired: Apr 7, 2016, 12:45 PM EDT
In force: 37 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon

Counties New Castle County, DE, Cecil County, MD, Chester County, PA, Delaware County, PA

The radar

The Philadelphia radar (KDIX), 104 km from the middle of the area, began a volume at 16:11 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
Apr 7, 12:08 PM EDT	TSTM WND DMG	2 Sse Atglen, PA	TREES DOWN... ONE ON A CAR... NEAR THE OCTORARA SCHOOLS.
Apr 7, 12:08 PM EDT	TSTM WND DMG	2 Sse Lenover, PA	LARGE SCORE BOARD BLOWN OVER AT THE OCTORARA ELEMENTARY/HIGH SCHOOL FOOTBALL FIELD NEAR ATGLEN. HIGH WINDS WERE ASSOCIATED WITH A BOWING SQUALL LINE.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Phillips Aaf/Abe, MD (KAPG), launched 12:00Z, 4.1 hours before the alert went out and 68 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: 32 J/kg
Mixed-layer CIN: -33 J/kg
Mixed-layer LCL: 605 m above ground
0-6 km bulk shear: 40 kt
0-1 km storm-relative helicity: 299 m²/s²
0-3 km storm-relative helicity: 259 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

703 
WUUS51 KPHI 071608
SVRPHI
DEC003-MDC015-PAC029-045-071645-
/O.NEW.KPHI.SV.W.0024.160407T1608Z-160407T1645Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1208 PM EDT THU APR 7 2016

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ  HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTHERN NEW CASTLE COUNTY IN NORTHERN DELAWARE...
  NORTHWESTERN CECIL COUNTY IN NORTHEASTERN MARYLAND...
  CHESTER COUNTY IN SOUTHEASTERN PENNSYLVANIA...
  DELAWARE COUNTY IN SOUTHEASTERN PENNSYLVANIA...

* UNTIL 1245 PM EDT

* AT 1206 PM EDT...DOPPLER RADAR INDICATED A LINE OF SEVERE
  THUNDERSTORMS CAPABLE OF PRODUCING DAMAGING WINDS IN EXCESS OF 60
  MPH. THESE STORMS WERE LOCATED ALONG A LINE EXTENDING FROM GAP TO
  NEAR COCHRANVILLE TO LOMBARD...AND MOVING EAST AT 50 MPH.

HEAVY RAIN IS ACCOMPANYING THIS LINE OF STORMS AND MAY QUICKLY DROP
ONE QUARTER TO ONE HALF OF AN INCH OF RAIN, WHICH MAY CAUSE PONDING
OF WATER IN LOW LYING AND POOR DRAINAGE AREAS. 

* SEVERE THUNDERSTORMS WILL BE NEAR...
  WEST GROVE AROUND 1210 PM EDT. 
  PARKESBURG AND KEMBLESVILLE AROUND 1215 PM EDT. 
  COATESVILLE...KENNETT SQUARE AND LADENBERG AROUND 1220 PM EDT. 
  PIKE CREEK...NORTH STAR...HOCKESSIN...GLENMOORE AND MARSHALLTON 
  AROUND 1225 PM EDT. 
  WESTTOWN...DOWNINGTOWN...ELSMERE...GREENVILLE...ELAM AND ASHLAND 
  AROUND 1230 PM EDT. 
  WILMINGTON...WEST CHESTER...CONCORDVILLE...LIONVILLE-MARCHWOOD...
  LIONVILLE...CHELSEA...CHEYNEY...TALLEYVILLE...GRADYVILLE AND CHESTER 
  SPRINGS AROUND 1235 PM EDT. 
  PHOENIXVILLE...ARDEN...LIMA AND CHESTER TOWNSHIP AROUND 1240 PM EDT. 
  CHESTER...YEADON...FOLCROFT...SWARTHMORE...EAST LANSDOWNE...PAOLI...
  NETHER PROVIDENCE TOWNSHIP...VALLEY FORGE...TINICUM TOWNSHIP AND 
  PHILADELPHIA INTERNATIONAL ARPT AROUND 1245 PM EDT. 

OTHER LOCATIONS IMPACTED BY THESE SEVERE THUNDERSTORMS INCLUDE
CLIFTON HEIGHTS...MARCUS HOOK...WOODLYN...ROSE VALLEY...BOOTHWYN...
TRAINER...SPRINGFIELD...SOUTH COATESVILLE...SHARON HILL AND COLWYN.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

SEVERE THUNDERSTORMS PRODUCE DAMAGING WINDS...LARGE HAIL...DEADLY
LIGHTNING AND VERY HEAVY RAIN. FOR YOUR PROTECTION...MOVE TO AN
INTERIOR ROOM ON THE LOWEST FLOOR OF YOUR HOME OR BUSINESS. HEAVY
RAINS FLOOD ROADS QUICKLY SO DO NOT DRIVE INTO AREAS WHERE WATER
COVERS THE ROAD.

THIS SEVERE THUNDERSTORM MAY CONTAIN LITTLE OR NO LIGHTNING. DO NOT
WAIT UNTIL YOU HEAR THUNDER BEFORE TAKING COVER.

&&

LAT...LON 3985 7602 3987 7600 3987 7599 3995 7600
      4004 7593 4008 7593 4016 7550 4014 7551
      4013 7546 4010 7546 4009 7542 4006 7539
      4007 7536 3994 7524 3988 7526 3986 7522
      3984 7536 3975 7547 3972 7603
TIME...MOT...LOC 1606Z 261DEG 42KT 3998 7603 3985 7592 3972 7597 

$$

MEOLA

1 follow-up statement

880 
WWUS51 KPHI 071638
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1238 PM EDT THU APR 7 2016

DEC003-MDC015-PAC029-045-071647-
/O.EXP.KPHI.SV.W.0024.000000T0000Z-160407T1645Z/
NEW CASTLE DE-CECIL MD-CHESTER PA-DELAWARE PA-
1238 PM EDT THU APR 7 2016

...THE SEVERE THUNDERSTORM WARNING FOR NORTHERN NEW CASTLE...
NORTHWESTERN CECIL...CHESTER AND DELAWARE COUNTIES WILL EXPIRE AT
1245 PM EDT...
            
THE STORMS WHICH PROMPTED THE WARNING HAVE 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
AND HEAVY RAIN ARE STILL POSSIBLE WITH THESE THUNDERSTORMS.

LAT...LON 3985 7602 3987 7600 3987 7599 3995 7600
      4004 7593 4008 7593 4016 7550 4014 7551
      4013 7546 4010 7546 4009 7542 4006 7539
      4007 7536 3994 7524 3988 7526 3986 7522
      3984 7536 3975 7547 3972 7603
TIME...MOT...LOC 1636Z 261DEG 42KT 3998 7603 3985 7592 3972 7597 

$$

MEOLA

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 7, 1:03 PM EDT	Special Weather Statement	PHI	Bucks, Delaware, Montgomery, Philadelphia	42 min
Apr 7, 1:34 PM EDT	Special Weather Statement	PHI	Bucks	56 min
Apr 7, 3:30 AM EDT	Wind Advisory	PHI	Caroline, Cecil, Kent, Queen Anne's, Talbot	12 hr
Apr 7, 10:49 AM EDT	Special Weather Statement	PHI	Caroline, Cecil, Kent, Queen Anne's, Talbot	86 min
Apr 7, 5:31 PM EDT	Special Weather Statement	PHI	Kent	44 min
Apr 7, 5:48 PM EDT	Special Weather Statement	PHI	Caroline, Queen Anne's, Talbot	42 min
Apr 6, 8:07 PM EDT	Coastal Flood Advisory	PHI	New Castle	5 hr
Apr 7, 12:22 PM EDT	Special Weather Statement	PHI	New Castle	38 min
Apr 7, 3:16 PM EDT	Special Weather Statement	PHI	Sussex	44 min
Apr 7, 6:19 PM EDT	Special Weather Statement	PHI	New Castle	56 min
Apr 7, 6:27 PM EDT	Special Weather Statement	PHI	Kent, Sussex	48 min
Apr 7, 6:37 PM EDT	Severe Thunderstorm Warning	PHI	Kent, New Castle, Sussex	38 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2016 Severe Thunderstorm Warnings in Maryland, 2016 Severe Thunderstorm Warnings in Delaware, 2016 Every severe thunderstorm warning in 2016

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.