Alert archive / Maryland / Special Weather Statements in 2013

Special Weather Statement, NWS Philadelphia/Mount Holly

October 7, 2013Chester County, Pennsylvania; New Castle County, Delaware; Cecil County, Kent County, Maryland

NWS Philadelphia/Mount Holly issued this special weather statement at Oct 7, 2013, 12:41 PM EDT for Chester County, Pennsylvania; New Castle County, Delaware; Cecil County, Kent County, Maryland. It was in force for 64 min. 4 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: Oct 7, 2013, 12:41 PM EDT (16:41 UTC)
Expired: Oct 7, 2013, 1:45 PM EDT
In force: 64 min
Issued by: NWS Philadelphia/Mount Holly

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

The radar

The Dover AFB radar (KDOX), 111 km from the middle of the area, began a volume at 16:47 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
Oct 7, 1:00 PM EDT	TSTM WND GST 57	Birdsboro, PA	A 57 MPH WIND GUST WAS MEASURED ON A HANDHELD ANEMOMETER DURING A LINE OF CONVECTION.
Oct 7, 1:08 PM EDT	TSTM WND DMG	Earl Twp, PA	TREES DOWN.
Oct 7, 1:10 PM EDT	TSTM WND DMG	North East, MD	TREE TOPS SNAPPED ON HILLCREST LANE. TIME OF EVENT ESTIMATED FROM RADAR.
Oct 7, 1:10 PM EDT	TSTM WND DMG	Northeast Heights, MD	DAMAGE TO CROPS

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, 4.7 hours before the alert went out and 33 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: 114 J/kg
Mixed-layer CIN: -7 J/kg
Mixed-layer LCL: 584 m above ground
0-6 km bulk shear: 48 kt
0-1 km storm-relative helicity: 149 m²/s²
0-3 km storm-relative helicity: 196 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.2

Open this sounding in Storm Lab

The text

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

515 
WWUS81 KPHI 071641
SPSPHI

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1241 PM EDT MON OCT 7 2013

DEZ001-MDZ008-012-PAZ060-101-102-071745-
BERKS PA-CECIL MD-EASTERN CHESTER PA-KENT MD-NEW CASTLE DE-
WESTERN CHESTER PA-
1241 PM EDT MON OCT 7 2013

...A LINE OF STRONG THUNDERSTORMS WILL AFFECT CECIL...CHESTER...
KENT...SOUTHEASTERN BERKS AND WESTERN NEW CASTLE COUNTIES...

AT 1235 PM EDT...A LINE OF STRONG THUNDERSTORMS WAS LOCATED FROM 
LEOLA TO FORT HOWARD...MOVING NORTHEAST AT 50 MPH. THESE STORMS ARE 
CAPABLE OF PRODUCING WIND GUSTS TO 5O MILES AN HOUR AND HEAVY 
RAINFALL AS THEY MOVE THROUGH THE REGION.  BE PREPARED FOR SHARP 
REDUCTIONS IN VISIBILITIES WHEN THE HEAVY RAIN MOVES THROUGH. 

THESE STORMS WILL BE NEAR ATGLEN AROUND 1250 PM...LORANE AROUND 100
PM...DOWNINGTOWN AROUND 110 PM...ODESSA AROUND 120 PM AND NEWPORT
AROUND 130 PM.

LAT...LON 3918 7628 3932 7619 3943 7601 3952 7599
      3954 7608 3972 7623 3977 7607 3988 7599
      4011 7595 4014 7589 4022 7600 4048 7560
      4036 7560 4024 7570 4024 7568 4024 7560
      3947 7558 3924 7596 3923 7604 3907 7623

$$

SZATKOWSKI

The office that day

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

Issued	Product	Office	Counties	Lasted
Oct 7, 1:30 PM EDT	Special Weather Statement	PHI	Hunterdon, Morris, Sussex, Warren	60 min
Oct 7, 1:37 PM EDT	Special Weather Statement	PHI	Salem	53 min
Oct 7, 1:59 PM EDT	Severe Thunderstorm Warning	PHI	Hunterdon	46 min
Oct 7, 2:24 PM EDT	Special Weather Statement	PHI	Morris, Somerset	51 min
Oct 7, 2:33 PM EDT	Special Weather Statement	PHI	Mercer, Middlesex	42 min
Oct 7, 3:02 PM EDT	Special Weather Statement	PHI	Mercer, Middlesex	43 min
Oct 7, 3:49 PM EDT	Special Marine Warning	PHI		56 min
Oct 7, 4:05 PM EDT	Special Weather Statement	PHI	Monmouth, Ocean	40 min
Oct 7, 11:31 AM EDT	Special Weather Statement	PHI	Berks, Chester	59 min
Oct 7, 11:50 AM EDT	Severe Thunderstorm Warning	PHI	Berks	40 min
Oct 7, 12:12 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Carbon, Lehigh, Monroe, Northampton	63 min
Oct 7, 12:49 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Chester, Montgomery	41 min
Oct 7, 1:05 PM EDT	Severe Thunderstorm Warning	PHI	Chester, Delaware	25 min
Oct 7, 1:33 PM EDT	Special Weather Statement	PHI	Bucks, Montgomery	42 min
Oct 7, 2:18 PM EDT	Severe Thunderstorm Warning	PHI	Kent, Sussex	57 min
Oct 7, 3:21 PM EDT	Special Weather Statement	PHI	Sussex	39 min

Nearby

Special Weather Statements in Maryland, 2013 Special Weather Statements in Pennsylvania, 2013 Special Weather Statements in Delaware, 2013 Every special weather statement in 2013

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.