Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2007
Severe Thunderstorm Warning 237, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Oct 19, 2007, 8:55 PM EDT for Chester County, Pennsylvania. It was in force for 33 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
- Oct 19, 2007, 8:55 PM EDT (00:55 UTC)
- Expired
- Oct 19, 2007, 9:28 PM EDT
- In force
- 33 min
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
County Chester County, PA
The radar
The Dover AFB radar (KDOX), 125 km from the middle of the area, began a volume at 00:55 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, 0.9 hours before the alert went out and 157 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.
- Mixed-layer CAPE
- 480 J/kg
- Mixed-layer CIN
- -17 J/kg
- Mixed-layer LCL
- 682 m above ground
- 0-6 km bulk shear
- 53 kt
- 0-1 km storm-relative helicity
- 98 m²/s²
- 0-3 km storm-relative helicity
- 186 m²/s²
- Significant tornado parameter
- 0.3
- Supercell composite
- 1.3
The text
As transmitted, in the capitals the NWS used until 2016.
000
WUUS51 KPHI 200055
SVRPHI
PAC029-200200-
/O.NEW.KPHI.SV.W.0237.071020T0055Z-071020T0200Z/
BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
855 PM EDT FRI OCT 19 2007
THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A
* SEVERE THUNDERSTORM WARNING FOR...
WESTERN CHESTER COUNTY IN SOUTHEAST PENNSYLVANIA...
* UNTIL 1000 PM EDT
* AT 853 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING DAMAGING WINDS IN EXCESS
OF 60 MPH. THIS STORM WAS LOCATED NEAR GLEN ROY...OR ABOUT 19
MILES NORTHWEST OF NEWARK...AND MOVING NORTHEAST AT 30 MPH.
* THE SEVERE THUNDERSTORM WILL BE NEAR...
MOUNT VERNON AND OXFORD BY 900 PM EDT...
HOMEVILLE BY 905 PM EDT...
COCHRANVILLE BY 910 PM EDT...
WEST GROVE AND 6 MILES SOUTHEAST OF PARKESBURG BY 915 PM EDT...
COATESVILLE BY 925 PM EDT...
DOPPLER RADAR HAS INDICATED SOME WEAK ROTATION WITHIN THIS STORM.
WHILE NOT IMMEDIATELY LIKELY...A TORNADO MAY STILL DEVELOP. IF A
TORNADO IS SPOTTED...ACT QUICKLY AND MOVE TO A PLACE OF SAFETY IN A
STURDY STRUCTURE...SUCH AS A BASEMENT OR SMALL INTERIOR ROOM.
THUNDERSTORMS ARE CAPABLE OF PRODUCING HEAVY RAINFALL WHICH MAY
RESULT IN LOCALIZED AREAS OF FLOODING. DO NOT DRIVE IN AREAS WHERE
WATER IS CROSSING THE ROAD.
LAT...LON 3978 7607 3985 7604 3988 7600 3992 7602
3994 7600 3997 7600 4000 7598 4010 7588
3981 7572 3972 7606 3972 7608 3976 7609
TIME...MOT...LOC 0055Z 240DEG 30KT 3980 7606
$$
TFG1 follow-up statement
000
WWUS51 KPHI 200128
SVSPHI
SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
926 PM EDT FRI OCT 19 2007
PAC029-200136-
/O.CAN.KPHI.SV.W.0237.000000T0000Z-071020T0200Z/
CHESTER PA-
926 PM EDT FRI OCT 19 2007
...THE SEVERE THUNDERSTORM WARNING FOR WESTERN CHESTER COUNTY IS
CANCELLED...
THE SEVERE THUNDERSTORM WARNING FOR THE WESTERN PART OF THE COUNTY
HAS BEEN CANCELLED. THE WARNING OF THE EASTERN HALF OF CHESTER
COUNTY REMAINS IN EFFECT.
LAT...LON 3978 7607 3985 7604 3988 7600 3992 7602
3994 7600 3997 7600 4000 7598 4010 7588
3981 7572 3972 7606 3972 7608 3976 7609
TIME...MOT...LOC 0126Z 240DEG 30KT 3993 7577
$$
TFGThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Oct 19, 8:33 PM EDT | Severe Thunderstorm Warning | PHI | Berks | 35 min |
| Oct 19, 9:18 PM EDT | Severe Thunderstorm Warning | PHI | Chester | 27 min |
Nearby
Severe Thunderstorm Warnings in Pennsylvania, 2007Every severe thunderstorm warning in 2007
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.