Alert archive / Pennsylvania / Special Weather Statements in 2012

Special Weather Statement, NWS Philadelphia/Mount Holly

May 15, 20125 counties in Pennsylvania

NWS Philadelphia/Mount Holly issued this special weather statement at May 15, 2012, 9:49 PM EDT for 5 counties in Pennsylvania. It was in force for 86 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: May 15, 2012, 9:49 PM EDT (01:49 UTC)
Expired: May 15, 2012, 11:15 PM EDT
In force: 86 min
Issued by: NWS Philadelphia/Mount Holly

Counties Berks County, PA, Bucks County, PA, Chester County, PA, Lehigh County, PA, Montgomery County, PA

The radar

The Philadelphia radar (KDIX), 126 km from the middle of the area, began a volume at 01:49 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, 1.8 hours before the alert went out and 183 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: 401 J/kg
Mixed-layer CIN: -9 J/kg
Mixed-layer LCL: 1311 m above ground
0-6 km bulk shear: 22 kt
0-1 km storm-relative helicity: 5 m²/s²
0-3 km storm-relative helicity: 58 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.1

Open this sounding in Storm Lab

The text

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

874 
WWUS81 KPHI 160149
SPSPHI

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
949 PM EDT TUE MAY 15 2012

PAZ060-061-067>069-160315-
BERKS PA-BUCKS PA-CHESTER PA-LEHIGH PA-MONTGOMERY PA-
949 PM EDT TUE MAY 15 2012

...STRONG THUNDERSTORMS WILL AFFECT BERKS...BUCKS...CHESTER...LEHIGH 
AND MONTGOMERY COUNTIES...

AT 945 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A 
STRONG THUNDERSTORMS IN BERKS AND CHESTER COUNTIES...MOVING NORTHEAST
AT 20 MPH.  VERY HEAVY RAIN WILL FALL FROM THESE STORM...AND WILL 
CAUSE WATER TO POND ON ROADS AND QUICKLY FILL ROADSIDE DITCHES AND 
SMALL STREAMS.

EXPECT SMALL HAIL AND FREQUENT...DANGEROUS CLOUD TO GROUND LIGHTNING
FROM THIS STORM.

LAT...LON 4072 7563 4026 7496 3978 7606 3983 7604
      3983 7602 3985 7603 3988 7600 3992 7600
      3998 7599 4003 7594 4011 7595 4014 7589
      4029 7610

$$

NIERENBERG

The office that day

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

Issued	Product	Office	Counties	Lasted
May 15, 8:19 PM EDT	Special Weather Statement	PHI	Hunterdon, Warren	86 min
May 15, 8:46 PM EDT	Areal Flood Warning	PHI	Warren	76 min
May 15, 9:56 PM EDT	Special Weather Statement	PHI	Morris, Somerset	94 min
May 15, 10:48 PM EDT	Special Weather Statement	PHI	Somerset	57 min
May 16, 2:20 AM EDT	Special Weather Statement	PHI	Mercer	55 min
May 16, 10:36 AM EDT	Small Craft Advisory for Hazardous Seas	PHI		7 hr
May 15, 9:00 PM EDT	Special Weather Statement	PHI	Berks	90 min
May 15, 10:45 PM EDT	Areal Flood Advisory	PHI	Chester	57 min
May 15, 11:05 PM EDT	Special Weather Statement	PHI	Bucks, Chester, Delaware, Montgomery	55 min
May 15, 11:24 PM EDT	Areal Flood Advisory	PHI	Chester, Montgomery	116 min
May 15, 11:38 PM EDT	Areal Flood Warning	PHI	Chester, Montgomery	4 hr
May 16, 12:12 AM EDT	Areal Flood Advisory	PHI	Chester, Delaware, Montgomery	3 hr
May 16, 12:20 AM EDT	Special Weather Statement	PHI	Delaware, Philadelphia	55 min
May 16, 12:34 AM EDT	Flash Flood Warning	PHI	Chester, Delaware, Montgomery	4 hr
May 16, 2:37 AM EDT	Areal Flood Warning	PHI	Philadelphia	3 hr
May 16, 4:27 AM EDT	Areal Flood Warning	PHI	Delaware	3 hr

Nearby

Special Weather Statements in Pennsylvania, 2012 Every 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.