Alert archive / Pennsylvania / Special Weather Statements in 2012

Special Weather Statement, NWS Philadelphia/Mount Holly

July 15, 2012Chester County, Montgomery County, Philadelphia County, Pennsylvania

NWS Philadelphia/Mount Holly issued this special weather statement at Jul 15, 2012, 8:27 PM EDT for Chester County, Montgomery County, Philadelphia County, Pennsylvania. It was in force for 63 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Jul 15, 2012, 8:27 PM EDT (00:27 UTC)
Expired
Jul 15, 2012, 9:30 PM EDT
In force
63 min
Issued by
NWS Philadelphia/Mount Holly

Counties Chester County, PA, Montgomery County, PA, Philadelphia County, PA

The radar

The Philadelphia radar (KDIX), 116 km from the middle of the area, began a volume at 00:26 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.

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 00:00Z, 0.5 hours before the alert went out and 188 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 2012-07-16Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 652 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Washington/Dulle, VA at 00:00Z on 2012-07-16The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 90 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
652 J/kg
Mixed-layer CIN
-91 J/kg
Mixed-layer LCL
1264 m above ground
0-6 km bulk shear
21 kt
0-1 km storm-relative helicity
90 m²/s²
0-3 km storm-relative helicity
119 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.5

Open this sounding in Storm Lab

The text

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

848 
WWUS81 KPHI 160027
SPSPHI

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
827 PM EDT SUN JUL 15 2012

NJZ018-PAZ067>071-160130-
BUCKS PA-CAMDEN NJ-CHESTER PA-DELAWARE PA-MONTGOMERY PA-
PHILADELPHIA PA-
827 PM EDT SUN JUL 15 2012

...A STRONG THUNDERSTORM WILL AFFECT BUCKS...CAMDEN...CHESTER...
DELAWARE...MONTGOMERY AND PHILADELPHIA COUNTIES...

AT 826 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM 15 MILES NORTHWEST OF WEST CHESTER...MOVING EAST
AT 25 MPH. THE THUNDERSTORM WILL BE NEAR PUGHTOWN...CHESTER SPRINGS
AROUND 845 PM...PHOENIXVILLE...SPRING CITY AROUND 900 PM...
EAGLEVILLE...TROOPER AROUND 915 PM...BLUE BELL AND NORTH WALES AROUND
930 PM.

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

LAT...LON 3998 7599 4003 7594 4010 7595 4012 7592
      4014 7587 4017 7582 4031 7510 3993 7504
      3991 7600

$$

HAYES

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 15, 8:04 PM EDTSpecial Weather StatementPHIAtlantic56 min
Jul 15, 8:11 PM EDTSpecial Weather StatementPHIGloucester, Salem64 min
Jul 15, 8:35 PM EDTSpecial Weather StatementPHIMercer, Middlesex, Monmouth55 min
Jul 15, 8:39 PM EDTSpecial Marine WarningPHI66 min
Jul 15, 8:58 PM EDTSpecial Weather StatementPHIBurlington, Camden62 min
Jul 15, 9:00 PM EDTSpecial Weather StatementPHIBurlington60 min
Jul 15, 9:21 PM EDTSpecial Weather StatementPHIMercer54 min
Jul 15, 9:33 PM EDTSpecial Weather StatementPHIMiddlesex, Monmouth57 min
Jul 15, 9:45 PM EDTSpecial Marine WarningPHI60 min
Jul 15, 9:52 PM EDTSpecial Weather StatementPHIOcean68 min
Jul 15, 9:55 PM EDTSevere Thunderstorm WarningPHIBurlington, Camden, Mercer, Monmouth, Ocean80 min
Jul 15, 10:14 PM EDTSpecial Marine WarningPHI79 min
Jul 15, 10:51 PM EDTSpecial Weather StatementPHIAtlantic, Camden, Gloucester, Salem54 min
Jul 15, 11:25 PM EDTSpecial Weather StatementPHIAtlantic, Ocean65 min
Jul 16, 3:35 AM EDTHeat AdvisoryPHIBurlington, Hunterdon, Middlesex, Monmouth, Morris, Ocean and 3 more62 hr
Jul 15, 8:30 PM EDTSevere Thunderstorm WarningPHIChester45 min
Jul 15, 9:16 PM EDTSpecial Weather StatementPHIChester59 min
Jul 15, 8:08 PM EDTSpecial Weather StatementPHINew Castle67 min
Jul 16, 4:32 PM EDTSpecial Weather StatementPHISussex88 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.