Alert archive / Maryland / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 141, NWS Philadelphia/Mount Holly

July 28, 2012Caroline County, Talbot County, Maryland

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 28, 2012, 7:22 PM EDT for Caroline County, Talbot County, Maryland. It was in force for 53 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, 7:22 PM EDT (23:22 UTC)
Expired: Jul 28, 2012, 8:15 PM EDT
In force: 53 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon

Counties Caroline County, MD, Talbot County, MD

The radar

The Dover AFB radar (KDOX), 51 km from the middle of the area, began a volume at 23:25 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, 8:09 PM EDT	HAIL 0.88	Preston, MD	NICKEL SIZE HAIL REPORTED IN PRESTON.
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.

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 12:00Z, 11.4 hours before the alert went out and 103 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: 899 J/kg
Mixed-layer CIN: -48 J/kg
Mixed-layer LCL: 840 m above ground
0-6 km bulk shear: 28 kt
0-1 km storm-relative helicity: -4 m²/s²
0-3 km storm-relative helicity: 101 m²/s²
Significant tornado parameter: 0.2
Supercell composite: 1.5

Open this sounding in Storm Lab

The text

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

777 
WUUS51 KPHI 282322
SVRPHI
MDC011-041-290015-
/O.NEW.KPHI.SV.W.0141.120728T2322Z-120729T0015Z/

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

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  CAROLINE COUNTY IN EASTERN MARYLAND...
  EASTERN TALBOT COUNTY IN EASTERN MARYLAND...
  THIS INCLUDES THE CITY OF EASTON...

* UNTIL 815 PM EDT

* AT 719 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 CORDOVA TO MATTHEWS TO EASTON
  TO HAMBLETON TO 6 MILES SOUTHWEST OF OXFORD...OR ALONG A LINE
  EXTENDING FROM 8 MILES NORTHEAST OF EASTON TO EASTON TO 6 MILES
  SOUTHWEST OF EASTON TO 14 MILES SOUTHWEST OF EASTON...AND MOVING
  EAST AT 15 MPH.

THESE STORMS HAS A HISTORY OF PRODUCING WIND DAMAGE IN ST MICHAELS. 

* SEVERE THUNDERSTORMS WILL BE NEAR...
  MATTHEWS AND HAMBLETON AROUND 730 PM EDT...
  GRIFFIN AROUND 735 PM EDT...
  JUMPTOWN AND TANYARD AROUND 740 PM EDT...
  RIDGELY AND TRAPPE AROUND 745 PM EDT...
  HARMONY AND DENTON AROUND 755 PM EDT...
  GREENSBORO AROUND 800 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 3860 7608 3860 7613 3864 7618 3866 7618
      3867 7621 3878 7611 3894 7606 3892 7596
      3896 7594 3900 7574 3865 7571 3870 7584
      3867 7594 3860 7598 3858 7607
TIME...MOT...LOC 2322Z 256DEG 15KT 3888 7598 3880 7599
          3876 7604 3870 7610 3861 7622

$$

HAYES

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 28, 3:12 PM EDT	Special Weather Statement	PHI	Cecil	63 min
Jul 28, 4:10 PM EDT	Severe Thunderstorm Warning	PHI	Cecil	65 min
Jul 28, 4:24 PM EDT	Areal Flood Advisory	PHI	Cecil	95 min
Jul 28, 5:20 PM EDT	Special Weather Statement	PHI	Cecil	55 min
Jul 28, 6:09 PM EDT	Special Weather Statement	PHI	Queen Anne's, Talbot	66 min
Jul 28, 6:41 PM EDT	Severe Thunderstorm Warning	PHI	Queen Anne's, Talbot	64 min
Jul 28, 7:57 PM EDT	Severe Thunderstorm Warning	PHI	Cecil	48 min

Nearby

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.