Alert archive / Pennsylvania / Special Weather Statements in 2012

Special Weather Statement, NWS Philadelphia/Mount Holly

July 7, 2012Chester County, Pennsylvania

NWS Philadelphia/Mount Holly issued this special weather statement at Jul 7, 2012, 8:45 PM EDT for Chester County, Pennsylvania. It was in force for 60 min. 2 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 7, 2012, 8:45 PM EDT (00:45 UTC)
Expired
Jul 7, 2012, 9:45 PM EDT
In force
60 min
Issued by
NWS Philadelphia/Mount Holly

County Chester County, PA

The radar

The Dover AFB radar (KDOX), 117 km from the middle of the area, began a volume at 00:44 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

TimeReportWhereRemark
Jul 7, 9:18 PM EDTHAIL 0.88Coatesville, PA
Jul 7, 9:22 PM EDTHAIL 1Coatesville, PA

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

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 00:00Z, 0.8 hours before the alert went out and 167 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-pSkew-T log-p diagram, Washington/Dulle, VA at 00:00Z on 2012-07-08Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Washington/Dulle, VA at 00:00Z on 2012-07-08The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 39 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
0 m above ground
0-6 km bulk shear
32 kt
0-1 km storm-relative helicity
39 m²/s²
0-3 km storm-relative helicity
75 m²/s²
Significant tornado parameter
0.0
Supercell composite
2.4

Open this sounding in Storm Lab

The text

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

584 
WWUS81 KPHI 080045
SPSPHI

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
845 PM EDT SAT JUL 7 2012

DEZ001-PAZ067-070-080145-
CHESTER PA-DELAWARE PA-NEW CASTLE DE-
845 PM EDT SAT JUL 7 2012

...A STRONG THUNDERSTORM WILL AFFECT CHESTER...DELAWARE AND NEW
CASTLE COUNTIES...

AT 844 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM 5 MILES SOUTH OF LANCASTER...MOVING EAST AT 45
MPH. THE THUNDERSTORM WILL BE NEAR ATGLEN...COCHRANVILLE AROUND 915
PM...ELAM...KENNETT SQUARE AROUND 930 PM...CONCORDVILLE AND CHELSEA
AROUND 945 PM.

WIND GUSTS TO 50 MPH AND SMALL HAIL ARE POSSIBLE WITH THIS STORM.

LAT...LON 3983 7602 3985 7603 3988 7600 3996 7600
      4003 7594 4008 7594 4001 7540 3972 7547
      3971 7552 3966 7555 3970 7579 3972 7579
      3972 7587 3976 7608

$$

HAYES

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 7, 8:33 PM EDTSpecial Marine WarningPHI44 min
Jul 7, 10:50 PM EDTSpecial Weather StatementPHIWarren55 min
Jul 7, 10:53 PM EDTSpecial Weather StatementPHIOcean52 min
Jul 7, 11:04 PM EDTSpecial Weather StatementPHIMiddlesex, Monmouth56 min
Jul 7, 11:36 PM EDTSpecial Weather StatementPHIHunterdon, Morris, Somerset, Sussex, Warren54 min
Jul 8, 1:06 AM EDTSpecial Weather StatementPHIHunterdon, Morris, Somerset, Sussex, Warren54 min
Jul 7, 9:05 PM EDTSevere Thunderstorm WarningPHIChester, Delaware32 min
Jul 8, 7:33 PM EDTSpecial Weather StatementPHISussex57 min
Jul 8, 6:16 PM EDTSpecial Weather StatementPHITalbot59 min

Nearby

Special Weather Statements in Pennsylvania, 2012Every special weather statement 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.