Alert archive / Maryland / Severe Thunderstorm Warnings in 2013

Severe Thunderstorm Warning 53, NWS Philadelphia/Mount Holly

June 28, 2013Cecil County, Maryland; Chester County, Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jun 28, 2013, 3:19 PM EDT for Cecil County, Maryland; Chester County, Pennsylvania. It was in force for 41 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Jun 28, 2013, 3:19 PM EDT (19:19 UTC)
Expired: Jun 28, 2013, 4:00 PM EDT
In force: 41 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon

Counties Cecil County, MD, Chester County, PA

The radar

The Dover AFB radar (KDOX), 118 km from the middle of the area, began a volume at 19:22 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.

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 28, 2:08 PM EDT	Severe Thunderstorm Watch	SPC	7 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 7.3 hours before the alert went out and 169 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: 34 J/kg
Mixed-layer CIN: -140 J/kg
Mixed-layer LCL: 1246 m above ground
0-6 km bulk shear: 27 kt
0-1 km storm-relative helicity: 66 m²/s²
0-3 km storm-relative helicity: 70 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.

456 
WUUS51 KPHI 281919
SVRPHI
MDC015-PAC029-282000-
/O.NEW.KPHI.SV.W.0053.130628T1919Z-130628T2000Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
319 PM EDT FRI JUN 28 2013

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTHEASTERN CECIL COUNTY IN NORTHEAST MARYLAND...
  SOUTHERN CHESTER COUNTY IN SOUTHEAST PENNSYLVANIA...

* UNTIL 400 PM EDT

* AT 318 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM. THE STORM WAS NEAR WEST GROVE...MOVING EAST AT
  25 MPH. THIS STORM IS CAPABLE OF PRODUCING DAMAGING WINDS IN EXCESS
  OF 60 MPH. 

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  WEST GROVE AND KEMBLESVILLE AROUND 330 PM EDT...
  LADENBERG AROUND 335 PM EDT...
  KENNETT SQUARE AND DOWNINGTOWN AROUND 345 PM EDT...
  MARSHALLTON AND DOWNINGTOWN AROUND 350 PM EDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

VERY HEAVY RAIN WILL ALSO OCCUR WITH THIS SEVERE THUNDERSTORM...WHICH
COULD FLOOD LOW LYING AREAS QUICKLY AND COVER ROADS WITH WATER. DO
NOT DRIVE INTO AREAS WHERE WATER COVERS THE ROAD.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 900 PM EDT FRIDAY
EVENING FOR DELAWARE AND NORTHEASTERN MARYLAND AND SOUTHERN NEW
JERSEY AND SOUTHEASTERN PENNSYLVANIA.

&&

LAT...LON 3988 7599 3992 7600 4009 7566 3989 7558
      3988 7560 3984 7560 3980 7571 3976 7575
      3969 7580 3968 7599 3985 7603
TIME...MOT...LOC 1919Z 265DEG 21KT 3981 7589

$$

FORECASTER:JJM

2 follow-up statements

601 
WWUS51 KPHI 281933
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
333 PM EDT FRI JUN 28 2013

MDC015-PAC029-282000-
/O.CON.KPHI.SV.W.0053.000000T0000Z-130628T2000Z/
CECIL MD-CHESTER PA-
333 PM EDT FRI JUN 28 2013

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 400 PM EDT
FOR SOUTHERN CHESTER AND NORTHEASTERN CECIL COUNTIES...

AT 331 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING DAMAGING WINDS IN
EXCESS OF 60 MPH. THIS STORM WAS LOCATED NEAR KEMBLESVILLE...OR 9
MILES NORTHWEST OF NEWARK...MOVING EAST AT 25 MPH.

THE SEVERE THUNDERSTORM WILL BE NEAR...
LADENBERG AND AVONDALE AROUND 340 PM EDT...
TOUGHKENAMON AND THORNDALE AROUND 345 PM EDT...
KENNETT SQUARE AND DOWNINGTOWN AROUND 350 PM EDT...
MARSHALLTON AROUND 355 PM EDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 900 PM EDT FRIDAY
EVENING FOR DELAWARE AND NORTHEASTERN MARYLAND AND SOUTHERN NEW
JERSEY AND SOUTHEASTERN PENNSYLVANIA.

&&

LAT...LON 3988 7599 3992 7600 4009 7566 3989 7558
      3988 7560 3984 7560 3980 7571 3976 7575
      3969 7580 3968 7599 3985 7603
TIME...MOT...LOC 1932Z 268DEG 24KT 3977 7586

$$

FORECASTER:JJM

019 
WWUS51 KPHI 281951
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
351 PM EDT FRI JUN 28 2013

MDC015-PAC029-282001-
/O.EXP.KPHI.SV.W.0053.000000T0000Z-130628T2000Z/
CECIL MD-CHESTER PA-
351 PM EDT FRI JUN 28 2013

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHERN CHESTER AND
NORTHEASTERN CECIL COUNTIES WILL EXPIRE AT 400 PM EDT...

THE SEVERE THUNDERSTORM WARNING WILL BE ALLOWED TO EXPIRE.
THE STORM THAT PROMPTED THE WARNING HAS DECREASED IN INTENSITY.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 900 PM EDT FRIDAY
EVENING FOR DELAWARE AND NORTHEASTERN MARYLAND AND SOUTHERN NEW
JERSEY AND SOUTHEASTERN PENNSYLVANIA.

LAT...LON 3988 7599 3992 7600 4009 7566 3989 7558
      3988 7560 3984 7560 3980 7571 3976 7575
      3969 7580 3968 7599 3985 7603
TIME...MOT...LOC 1951Z 268DEG 24KT 3977 7570

$$

FORECASTER:JJM

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 28, 4:20 PM EDT	Severe Thunderstorm Warning	PHI	Cecil	55 min
Jun 28, 4:27 PM EDT	Tornado Warning	PHI	Cecil	33 min
Jun 28, 4:47 PM EDT	Special Weather Statement	PHI	Caroline, Kent, Queen Anne's, Talbot	73 min
Jun 28, 4:50 PM EDT	Severe Thunderstorm Warning	PHI	Cecil	55 min
Jun 28, 5:09 PM EDT	Flash Flood Warning	PHI	Cecil	11 hr
Jun 28, 5:14 PM EDT	Severe Thunderstorm Warning	PHI	Caroline, Queen Anne's, Talbot	46 min
Jun 28, 6:09 PM EDT	Severe Thunderstorm Warning	PHI	Caroline	96 min
Jun 27, 8:50 PM EDT	Areal Flood Advisory	PHI	Carbon	3 hr
Jun 27, 10:00 PM EDT	Areal Flood Advisory	PHI	Bucks, Lehigh, Monroe, Northampton	3 hr
Jun 27, 10:04 PM EDT	River Flood Warning	PHI	Chester	6 hr
Jun 28, 3:33 PM EDT	Areal Flood Advisory	PHI	Chester, Delaware	117 min
Jun 28, 4:23 PM EDT	Special Weather Statement	PHI	Delaware, Philadelphia	52 min
Jun 28, 5:49 PM EDT	Flash Flood Warning	PHI	Delaware	4 hr
Jun 28, 6:04 PM EDT	Special Weather Statement	PHI	Carbon	56 min
Jun 28, 6:21 PM EDT	Flash Flood Warning	PHI	Carbon	4 hr
Jun 28, 6:43 PM EDT	Flash Flood Warning	PHI	Monroe	4 hr
Jun 28, 7:32 PM EDT	Areal Flood Advisory	PHI	Lehigh, Northampton	3 hr

Nearby

Severe Thunderstorm Warnings in Maryland, 2013 Severe Thunderstorm Warnings in Pennsylvania, 2013 Every severe thunderstorm warning in 2013

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.