Alert archive / Maryland / Severe Thunderstorm Warnings in 2014

Severe Thunderstorm Warning 156, NWS Philadelphia/Mount Holly

September 2, 2014New Castle County, Delaware; Cecil County, Kent County, Maryland

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Sep 2, 2014, 8:38 PM EDT for New Castle County, Delaware; Cecil County, Kent County, Maryland. It was in force for 52 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: Sep 2, 2014, 8:38 PM EDT (00:38 UTC)
Expired: Sep 2, 2014, 9:30 PM EDT
In force: 52 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon

Counties New Castle County, DE, Cecil County, MD, Kent County, MD

The radar

The Dover AFB radar (KDOX), 85 km from the middle of the area, began a volume at 00:40 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
Sep 2, 9:02 PM EDT	TSTM WND DMG	Christiana, DE	A FEW WIRES DOWN

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 00:00Z, 0.6 hours before the alert went out and 151 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: 1100 J/kg
Mixed-layer CIN: -90 J/kg
Mixed-layer LCL: 1131 m above ground
0-6 km bulk shear: 40 kt
0-1 km storm-relative helicity: 197 m²/s²
0-3 km storm-relative helicity: 305 m²/s²
Significant tornado parameter: 0.8
Supercell composite: 5.3

Open this sounding in Storm Lab

The text

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

842 
WUUS51 KPHI 030038
SVRPHI
DEC003-MDC015-029-030130-
/O.NEW.KPHI.SV.W.0156.140903T0038Z-140903T0130Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
838 PM EDT TUE SEP 2 2014

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NEW CASTLE COUNTY IN NORTHERN DELAWARE...
  CECIL COUNTY IN NORTHEAST MARYLAND...
  NORTHERN KENT COUNTY IN NORTHEAST MARYLAND...

* UNTIL 930 PM EDT

* AT 833 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM. THE STORM WAS NEAR HAVRE DE GRACE...MOVING
  EAST AT 35 MPH. THIS STORM IS CAPABLE OF PRODUCING DAMAGING WINDS
  IN EXCESS OF 60 MPH. 

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  HOLLYWOOD BEACH AND NORTH EAST AROUND 845 PM EDT...
  CAYOTS AND CECILTON AROUND 850 PM EDT...
  BRANTWOOD AND BOHEMIAS MILLS AROUND 855 PM EDT...
  MOUNT PLEASANT AND MIDDLETOWN AROUND 900 PM EDT...
  SAINT GEORGES AND BEAR AROUND 905 PM EDT...
  SAINT GEORGES AND DELAWARE CITY AROUND 910 PM EDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS A DANGEROUS STORM. IF YOU ARE IN ITS PATH...MOVE INDOORS TO A
STURDY BUILDING AND STAY AWAY FROM WINDOWS. WHEN IT IS SAFE TO DO
SO...REPORT SEVERE WEATHER TO LOCAL LAW ENFORCEMENT OR TO THE
NATIONAL WEATHER SERVICE.

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.

FREQUENT CLOUD TO GROUND LIGHTNING IS OCCURRING WITH THIS SEVERE
THUNDERSTORM. WHEN THUNDER ROARS...MOVE INDOORS! REMEMBER...IF YOU
CAN HEAR THUNDER...YOU ARE CLOSE ENOUGH TO BE STRUCK BY LIGHTNING.

&&

LAT...LON 3944 7600 3952 7599 3956 7610 3960 7611
      3966 7608 3975 7549 3971 7549 3962 7560
      3959 7559 3964 7557 3951 7555 3947 7558
      3937 7551 3929 7619 3932 7619
TIME...MOT...LOC 0038Z 267DEG 36KT 3951 7603

$$

NIERENBERG

1 follow-up statement

291 
WWUS51 KPHI 030114
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
914 PM EDT TUE SEP 2 2014

MDC015-029-030124-
/O.CAN.KPHI.SV.W.0156.000000T0000Z-140903T0130Z/
CECIL MD-KENT MD-
914 PM EDT TUE SEP 2 2014

...THE SEVERE THUNDERSTORM WARNING FOR NORTHERN KENT AND CECIL
COUNTIES IS CANCELLED...

THE THUNDERSTORMS HAVE MOVED OUT OF CECIL AND KENT COUNTIES, SO THE 
SEVERE THUNDERSTORM WARNING HAS BEEN CANCELLED.

LAT...LON 3975 7549 3971 7549 3971 7551 3969 7552
      3962 7560 3960 7560 3959 7559 3964 7557
      3951 7555 3947 7558 3937 7551 3934 7575
      3970 7579
TIME...MOT...LOC 0114Z 267DEG 36KT 3952 7556

$$

DEC003-030130-
/O.CON.KPHI.SV.W.0156.000000T0000Z-140903T0130Z/
NEW CASTLE DE-
914 PM EDT TUE SEP 2 2014

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 930 PM EDT
FOR CENTRAL NEW CASTLE COUNTY...

AT 909 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 SAINT GEORGES...OR 13
MILES SOUTHEAST OF NEWARK...MOVING EAST AT 40 MPH.

THIS IS A DANGEROUS STORM. IF YOU ARE IN ITS PATH...MOVE INDOORS TO A
STURDY BUILDING AND STAY AWAY FROM WINDOWS. WHEN IT IS SAFE TO DO
SO...REPORT SEVERE WEATHER TO LOCAL LAW ENFORCEMENT OR TO THE
NATIONAL WEATHER SERVICE.

LAT...LON 3975 7549 3971 7549 3971 7551 3969 7552
      3962 7560 3960 7560 3959 7559 3964 7557
      3951 7555 3947 7558 3937 7551 3934 7575
      3970 7579
TIME...MOT...LOC 0114Z 267DEG 36KT 3952 7556

$$

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 2, 8:25 PM EDT	Special Weather Statement	PHI	New Castle	65 min
Sep 2, 9:05 PM EDT	Special Weather Statement	PHI	Kent	70 min
Sep 2, 9:31 PM EDT	Special Weather Statement	PHI	Sussex	89 min
Sep 2, 11:43 PM EDT	Special Weather Statement	PHI	Caroline, Queen Anne's, Talbot	62 min
Sep 3, 12:52 AM EDT	Special Weather Statement	PHI	Caroline	53 min
Sep 3, 1:01 AM EDT	Areal Flood Advisory	PHI	Caroline, Queen Anne's, Talbot	3 hr

Nearby

Severe Thunderstorm Warnings in Maryland, 2014 Severe Thunderstorm Warnings in Delaware, 2014 Every severe thunderstorm warning in 2014

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.