Alert archive / Delaware / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 144, NWS Philadelphia/Mount Holly

July 28, 2012Caroline County, Maryland; Kent County, Sussex County, Delaware

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 28, 2012, 8:09 PM EDT for Caroline County, Maryland; Kent County, Sussex County, Delaware. It was in force for 66 min. 3 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: Jul 28, 2012, 8:09 PM EDT (00:09 UTC)
Expired: Jul 28, 2012, 9:15 PM EDT
In force: 66 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon

Counties Kent County, DE, Sussex County, DE, Caroline County, MD

The radar

The Dover AFB radar (KDOX), 10 km from the middle of the area, began a volume at 00:12 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
Jul 28, 8:12 PM EDT	TSTM WND DMG	Federalsburg, MD	TREES AND WIRES DOWN IN FEDERALSBURG.
Jul 28, 8:12 PM EDT	HAIL 0.88	Federalsburg, MD	NICKEL SIZE HAIL REPORTED IN FEDERALSBURG.
Jul 28, 8:38 PM EDT	HAIL 0.5	Seaford, DE

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
Jul 28, 1:36 PM EDT	Severe Thunderstorm Watch	SPC	8 hr

The nearest sounding before it

Wallops Is Stn, VA (KWAL), launched 00:00Z, 0.2 hours before the alert went out and 90 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: 1078 J/kg
Mixed-layer CIN: -39 J/kg
Mixed-layer LCL: 1476 m above ground
0-6 km bulk shear: 28 kt
0-1 km storm-relative helicity: -8 m²/s²
0-3 km storm-relative helicity: -7 m²/s²
Significant tornado parameter: -0.0
Supercell composite: -0.6

Open this sounding in Storm Lab

The text

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

101 
WUUS51 KPHI 290009
SVRPHI
DEC001-005-MDC011-290115-
/O.NEW.KPHI.SV.W.0144.120729T0009Z-120729T0115Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
809 PM EDT SAT JUL 28 2012

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHERN KENT COUNTY IN CENTRAL DELAWARE...
  SUSSEX COUNTY IN CENTRAL DELAWARE...
  THIS INCLUDES THE CITY OF GEORGETOWN...
  SOUTHEASTERN CAROLINE COUNTY IN EASTERN MARYLAND...

* UNTIL 915 PM EDT

* AT 806 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 ANDREWSVILLE TO SEAFORD TO 
  13 MILES WEST OF LAUREL TO 19 MILES SOUTHWEST OF 
  FEDERALSBURG......AND MOVING EAST AT 30 MPH.

* SEVERE THUNDERSTORMS WILL BE NEAR...
  ANDREWSVILLE AROUND 815 PM EDT...
  SEAFORD AND BRIDGEVILLE AROUND 820 PM EDT...
  MILFORD...SYCAMORE AND ELLENDALE AROUND 840 PM EDT...
  LAUREL AROUND 845 PM EDT...
  GEORGETOWN AROUND 850 PM EDT...
  SLAUGHTER BEACH AND MILTON AROUND 855 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 1000 PM EDT
SATURDAY EVENING FOR NORTHERN DELAWARE AND NORTHEASTERN MARYLAND AND
NEW JERSEY AND EASTERN PENNSYLVANIA.

&&

LAT...LON 3864 7571 3868 7576 3868 7578 3886 7574
      3898 7530 3892 7530 3879 7515 3879 7511
      3881 7509 3876 7507 3870 7513 3859 7536
      3849 7570
TIME...MOT...LOC 0009Z 249DEG 25KT 3884 7567 3863 7569
          3850 7577 3845 7592

$$

HAYES

1 follow-up statement

555 
WWUS51 KPHI 290048
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
848 PM EDT SAT JUL 28 2012

MDC011-290058-
/O.CAN.KPHI.SV.W.0144.000000T0000Z-120729T0115Z/
CAROLINE MD-
848 PM EDT SAT JUL 28 2012

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN CAROLINE COUNTY
IS CANCELLED...

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 1000 PM EDT
SATURDAY EVENING FOR NORTHERN DELAWARE AND NORTHEASTERN MARYLAND AND
NEW JERSEY AND EASTERN PENNSYLVANIA.

LAT...LON 3851 7564 3865 7567 3871 7568 3872 7567
      3887 7567 3898 7530 3892 7530 3879 7515
      3879 7511 3881 7509 3876 7507 3870 7513
      3859 7536
TIME...MOT...LOC 0048Z 249DEG 25KT 3893 7534 3872 7536
          3859 7545 3854 7560

$$

DEC001-005-290115-
/O.CON.KPHI.SV.W.0144.000000T0000Z-120729T0115Z/
KENT DE-SUSSEX DE-
848 PM EDT SAT JUL 28 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 915 PM EDT
FOR SUSSEX AND SOUTHEASTERN KENT COUNTIES...

AT 846 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 SLAUGHTER BEACH TO
GEORGETOWN TO SYCAMORE TO BETHEL...OR ALONG A LINE EXTENDING FROM 17
MILES NORTH OF GEORGETOWN TO GEORGETOWN TO 8 MILES SOUTHWEST OF
GEORGETOWN TO 12 MILES NORTH OF SALISBURY...MOVING EAST AT 30 MPH.

SEVERE THUNDERSTORMS WILL BE NEAR...
  SLAUGHTER BEACH AND MILTON BY 855 PM EDT...
  LEWES AND CAPE HENLOPEN STATE PARK BY 915 PM EDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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 1000 PM EDT
SATURDAY EVENING FOR NORTHERN DELAWARE AND NORTHEASTERN MARYLAND AND
NEW JERSEY AND EASTERN PENNSYLVANIA.

&&

LAT...LON 3851 7564 3865 7567 3871 7568 3872 7567
      3887 7567 3898 7530 3892 7530 3879 7515
      3879 7511 3881 7509 3876 7507 3870 7513
      3859 7536
TIME...MOT...LOC 0048Z 249DEG 25KT 3893 7534 3872 7536
          3859 7545 3854 7560

$$

HAYES

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 28, 9:38 PM EDT	Special Weather Statement	PHI	Kent	67 min
Jul 28, 8:41 PM EDT	Special Weather Statement	PHI	New Castle	64 min
Jul 28, 8:51 PM EDT	Special Weather Statement	PHI	Sussex	54 min
Jul 28, 9:21 PM EDT	Severe Thunderstorm Warning	PHI	Sussex	23 min
Jul 28, 9:28 PM EDT	Special Weather Statement	PHI	Sussex	62 min
Jul 28, 10:15 PM EDT	Areal Flood Advisory	PHI	Sussex	69 min
Jul 29, 2:23 PM EDT	Special Weather Statement	PHI	Sussex	52 min
Jul 29, 3:45 PM EDT	Special Weather Statement	PHI	Sussex	60 min

Nearby

Severe Thunderstorm Warnings in Delaware, 2012 Severe Thunderstorm Warnings in Maryland, 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.