Alert archive / Delaware / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 62, NWS Philadelphia/Mount Holly

June 29, 2012New Castle County, Delaware

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jun 29, 2012, 11:50 PM EDT for New Castle County, Delaware. It was in force for 55 min. 7 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: Jun 29, 2012, 11:50 PM EDT (03:50 UTC)
Expired: Jun 30, 2012, 12:45 AM EDT
In force: 55 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon

County New Castle County, DE

The radar

The Dover AFB radar (KDOX), 79 km from the middle of the area, began a volume at 03:53 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 29, 11:55 PM EDT	HAIL 0.75	Middletown, DE
Jun 30, 12:10 AM EDT	TSTM WND DMG	Odessa, DE	LARGE TREE LIMBS DOWN
Jun 30, 12:15 AM EDT	TSTM WND DMG	Middletown, DE	MULTIPLE TREES REPORTED DOWN IN MIDDLETOWN.
Jun 30, 12:15 AM EDT	HAIL 1.75	Newark, DE
Jun 30, 12:18 AM EDT	HAIL 0.88	Newark, DE
Jun 30, 12:21 AM EDT	HAIL 0.75	New Castle, DE
Jun 30, 12:25 AM EDT	TSTM WND DMG	Middletown, DE	POLES SNAPPED. WIND GUSTS ESTIMATED IN EXCESS OF 70 MPH.

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 29, 10:09 PM EDT	Severe Thunderstorm Watch	SPC	4 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 00:00Z, 3.8 hours before the alert went out and 168 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: 5490 J/kg
Mixed-layer CIN: -14 J/kg
Mixed-layer LCL: 1596 m above ground
0-6 km bulk shear: 35 kt
0-1 km storm-relative helicity: 25 m²/s²
0-3 km storm-relative helicity: 102 m²/s²
Significant tornado parameter: 0.9
Supercell composite: 12.1

Open this sounding in Storm Lab

The text

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

984 
WUUS51 KPHI 300350
SVRPHI
DEC003-300445-
/O.NEW.KPHI.SV.W.0062.120630T0350Z-120630T0445Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1150 PM EDT FRI JUN 29 2012

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NEW CASTLE COUNTY IN NORTHERN DELAWARE...
  THIS INCLUDES THE CITIES OF...WILMINGTON...NEWARK...MIDDLETOWN...

* UNTIL 1245 AM EDT

* AT 1149 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL...AND
  DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS LOCATED NEAR
  MIDDLETOWN...AND MOVING EAST AT 30 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  PORT PENN AROUND 1155 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 200 AM EDT
SATURDAY MORNING FOR NORTHERN DELAWARE AND NORTHEASTERN MARYLAND AND
SOUTHERN NEW JERSEY.

&&

LAT...LON 3972 7578 3973 7551 3969 7552 3964 7559
      3960 7560 3964 7557 3952 7555 3946 7558
      3942 7553 3937 7551 3935 7554 3935 7555
      3933 7556 3930 7576
TIME...MOT...LOC 0350Z 259DEG 44KT 3946 7562

$$

AMC

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 29, 11:22 PM EDT	Special Weather Statement	PHI	New Castle	53 min
Jun 29, 11:38 PM EDT	Severe Thunderstorm Warning	PHI	Kent, Sussex	67 min
Jun 30, 12:18 AM EDT	Severe Thunderstorm Warning	PHI	New Castle	72 min
Jun 30, 12:45 AM EDT	Special Weather Statement	PHI	Kent, New Castle, Sussex	60 min
Jun 30, 3:48 AM EDT	Heat Advisory	PHI	Kent, Sussex	16 hr

Nearby

Severe Thunderstorm Warnings in Delaware, 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.