Alert archive / Maryland / Severe Thunderstorm Warnings in 2009

Severe Thunderstorm Warning 62, NWS Philadelphia/Mount Holly

June 9, 20095 counties in Maryland; Kent County, New Castle County, Delaware

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jun 9, 2009, 5:13 PM EDT for 5 counties in Maryland; Kent County, New Castle County, Delaware. It was in force for 92 min. 5 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 9, 2009, 5:13 PM EDT (21:13 UTC)
Expired: Jun 9, 2009, 6:45 PM EDT
In force: 92 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon

Counties Kent County, DE, New Castle County, DE, Caroline County, MD, Cecil County, MD, Kent County, MD, Queen Anne's County, MD, Talbot County, MD

The radar

The Dover AFB radar (KDOX), 64 km from the middle of the area, began a volume at 21:13 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 9, 5:53 PM EDT	HAIL 0.25	Galena, MD	QUARTER INCH HAIL REPORTED IN GALENA.
Jun 9, 6:30 PM EDT	TSTM WND GST 51	Greensboro, MD	ESTIMATED WIND GUST OF 51MPH IN GREENSBORO.
Jun 9, 6:42 PM EDT	TSTM WND DMG	Clayton, DE	THUNDERSTORM WINDS REMOVED SHINGLES FROM A HOUSE AND CAUSED A PORCH TO COLLAPSE IN CLAYTON.
Jun 9, 6:42 PM EDT	TSTM WND GST 65	1 Sw Clayton, DE	ESTIMATED 65MPH WIND GUST TOPPLED 100LBS PROPANE TANKS NEAR CLAYTON.
Jun 9, 6:50 PM EDT	HAIL 0.88	5 Nw Hazlettville, DE	NICKEL SIZE HAIL SW OF HARTLY.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Phillips Aaf/Abe, MD (KAPG), launched 12:00Z, 9.2 hours before the alert went out and 58 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: 1272 J/kg
Mixed-layer CIN: -67 J/kg
Mixed-layer LCL: 804 m above ground
0-6 km bulk shear: 28 kt
0-1 km storm-relative helicity: 87 m²/s²
0-3 km storm-relative helicity: 108 m²/s²
Significant tornado parameter: 0.3
Supercell composite: 1.9

Open this sounding in Storm Lab

The text

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

000 
WUUS51 KPHI 092113
SVRPHI
DEC001-003-MDC011-015-029-035-041-092245-
/O.NEW.KPHI.SV.W.0062.090609T2113Z-090609T2245Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
513 PM EDT TUE JUN 9 2009

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  KENT COUNTY IN CENTRAL DELAWARE...
  THIS INCLUDES THE CITY OF DOVER...
  CAROLINE COUNTY IN EASTERN MARYLAND...
  TALBOT COUNTY IN EASTERN MARYLAND...
  THIS INCLUDES THE CITY OF EASTON...
  SOUTHEASTERN CECIL COUNTY IN NORTHEAST MARYLAND...
  KENT COUNTY IN NORTHEAST MARYLAND...
  QUEEN ANNES COUNTY IN NORTHEAST MARYLAND...
  THIS INCLUDES THE CITY OF CENTERVILLE...
  SOUTHERN NEW CASTLE COUNTY IN NORTHERN DELAWARE...
  THIS INCLUDES THE CITY OF MIDDLETOWN...

* UNTIL 645 PM EDT

* AT 511 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING NICKEL SIZE HAIL...AND
  DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS LOCATED NEAR   
  MIDDLETOWN...AND MOVING SOUTHEAST AT 10 MPH.  ADDITIONALLY, A LINE 
  OF SEVERE THUNDERSTORMS EXTENDED FROM NEAR HAVRE DE GRACE MARYLAND 
  TO NEAR BALTIMORE.  THESE STORMS WERE MOVING TO THE SOUTHEAST.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  MIDDLETOWN AND WARWICK AROUND 525 PM EDT...
  7 MILES NORTHEAST OF SASSAFRAS AROUND 540 PM EDT...
  7 MILES NORTHEAST OF DELANEY CORNER AROUND 620 PM EDT...
  GREEN SPRING AROUND 635 PM EDT...
  SMYRNA...CLAYTON AND 7 MILES NORTH OF CHESWOLD AROUND 645 PM EDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 800 PM EDT
TUESDAY EVENING FOR NORTHEASTERN PENNSYLVANIA.

&&

LAT...LON 3873 7625 3866 7635 3878 7639 3887 7625
      3882 7621 3883 7620 3894 7624 3884 7638
      3886 7639 3905 7631 3901 7617 3910 7615
      3901 7619 3915 7628 3932 7619 3966 7563
      3899 7534 3884 7573 3860 7605
TIME...MOT...LOC 2111Z 326DEG 7KT 3947 7574

$$

NIERENBERG

1 follow-up statement

000 
WWUS51 KPHI 092154
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
554 PM EDT TUE JUN 9 2009

DEC001-003-MDC011-015-029-035-041-092245-
/O.CON.KPHI.SV.W.0062.000000T0000Z-090609T2245Z/
KENT DE-CAROLINE MD-CECIL MD-KENT MD-NEW CASTLE DE-QUEEN ANNES MD-
TALBOT MD-
554 PM EDT TUE JUN 9 2009

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 645 PM EDT
FOR TALBOT...QUEEN ANNES...SOUTHERN NEW CASTLE...KENT...SOUTHEASTERN
CECIL...CAROLINE AND KENT COUNTIES...

AT 548 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING NICKEL
SIZE HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH.  THESE STORMS 
WERE LOCATED ALONG A LINE EXTENDING FROM 23 MILES SOUTHWEST OF 
ELKTON TO 15 MILES WEST OF CENTERVILLE TO 28 MILES WEST OF 
EASTON...MOVING SOUTHEAST AT 30 MPH.

SEVERE THUNDERSTORMS WILL BE NEAR...
  NEWTOWN...STEVENSVILLE SOUTH AND STEVENSVILLE BY 600 PM EDT...
  LANGFORD...CHESTER AND BETTERTON BY 605 PM EDT...
  OLD TOWN AND GRASONVILLE BY 610 PM EDT...
  TILGHMAN ISLAND AND TALBOT BY 615 PM EDT...

THESE STORMS HAVE A HISTORY OF PRODUCING HAIL AND STRONG WINDS ON 
THE WEST SIDE OF CHESAPEAKE BAY.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 800 PM EDT
TUESDAY EVENING FOR NORTHEASTERN PENNSYLVANIA.

&&

LAT...LON 3873 7625 3866 7635 3878 7639 3887 7625
      3882 7621 3883 7620 3894 7624 3884 7638
      3886 7639 3905 7631 3901 7617 3910 7615
      3901 7619 3915 7628 3932 7619 3966 7563
      3899 7534 3884 7573 3860 7605
TIME...MOT...LOC 2151Z 302DEG 25KT 3944 7619 3909 7631
          3880 7656

$$

AMC

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 9, 1:49 PM EDT	Flash Flood Watch	PHI	Cecil	5 hr
Jun 9, 3:14 PM EDT	Tornado Warning	PHI	Cecil	46 min
Jun 9, 3:29 PM EDT	Severe Thunderstorm Warning	PHI	Cecil	61 min
Jun 9, 4:19 PM EDT	Severe Thunderstorm Warning	PHI	Cecil, Kent, Queen Anne's	56 min
Jun 9, 5:19 PM EDT	Areal Flood Warning	PHI	Cecil	71 min
Jun 9, 8:20 AM EDT	Areal Flood Advisory	PHI	New Castle	3 hr
Jun 9, 8:31 AM EDT	Severe Thunderstorm Warning	PHI	Sussex	59 min
Jun 9, 9:09 AM EDT	Areal Flood Advisory	PHI	Kent, Sussex	3 hr
Jun 9, 6:57 PM EDT	Severe Thunderstorm Warning	PHI	Kent	39 min

Nearby

Severe Thunderstorm Warnings in Maryland, 2009 Severe Thunderstorm Warnings in Delaware, 2009 Every severe thunderstorm warning in 2009

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.