Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2015
Severe Thunderstorm Warning 117, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Oct 9, 2015, 4:39 PM EDT for 5 counties in Pennsylvania. It was in force for 51 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 9, 2015, 4:39 PM EDT (20:39 UTC)
- Expired
- Oct 9, 2015, 5:30 PM EDT
- In force
- 51 min
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
Counties Berks County, PA, Chester County, PA, Delaware County, PA, Montgomery County, PA, Philadelphia County, PA
The radar
The Philadelphia radar (KDIX), 94 km from the middle of the area, began a volume at 20:42 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 9, 4:40 PM EDT | TSTM WND DMG | East Vincent Twp, PA | WIRES DOWN ON HICKORY GROVE ROAD. TIME ESTIMATED FROM RADAR. |
| Oct 9, 4:46 PM EDT | TSTM WND DMG | Royersford, PA | TREES DOWN. TIME ESTIMATED BY RADAR. |
| Oct 9, 4:46 PM EDT | TSTM WND DMG | Royersford, PA | TREES DOWN. TIME ESTIMATED BY RADAR. |
| Oct 9, 5:22 PM EDT | TSTM WND DMG | West Oak Lane, PA | TREES DOWN . |
Local storm reports filed while the alert was in force, from inside its polygon or its counties.
The watch it was issued in
The SPC watch in force over the same counties when this warning went out.
| Issued | Product | Office | Lasted |
|---|---|---|---|
| Oct 9, 3:34 PM EDT | Severe Thunderstorm Watch | SPC | 4 hr |
The nearest sounding before it
Washington/Dulle, VA (KIAD), launched 12:00Z, 8.7 hours before the alert went out and 214 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
- 43 J/kg
- Mixed-layer CIN
- -181 J/kg
- Mixed-layer LCL
- 1203 m above ground
- 0-6 km bulk shear
- 37 kt
- 0-1 km storm-relative helicity
- 114 m²/s²
- 0-3 km storm-relative helicity
- 126 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
094 WUUS51 KPHI 092039 SVRPHI PAC011-029-045-091-101-092130- /O.NEW.KPHI.SV.W.0117.151009T2039Z-151009T2130Z/ BULLETIN - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE MOUNT HOLLY NJ 439 PM EDT FRI OCT 9 2015 THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A * SEVERE THUNDERSTORM WARNING FOR... NORTHEASTERN CHESTER COUNTY IN SOUTHEASTERN PENNSYLVANIA... SOUTHEASTERN BERKS COUNTY IN EASTERN PENNSYLVANIA... NORTHEASTERN DELAWARE COUNTY IN SOUTHEASTERN PENNSYLVANIA... MONTGOMERY COUNTY IN SOUTHEASTERN PENNSYLVANIA... PHILADELPHIA COUNTY IN SOUTHEASTERN PENNSYLVANIA... * UNTIL 530 PM EDT * AT 437 PM EDT...DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM CAPABLE OF PRODUCING DAMAGING WINDS IN EXCESS OF 65 MPH. THIS STORM WAS LOCATED OVER PUGHTOWN...OR 12 MILES NORTH OF WEST CHESTER...AND MOVING EAST AT 45 MPH. PENNY SIZE HAIL MAY ALSO ACCOMPANY THE DAMAGING WINDS. * LOCATIONS IMPACTED INCLUDE... PHILADELPHIA...NORRISTOWN...POTTSTOWN...PHOENIXVILLE...LANSDALE... WEST NORRITON...EAST NORRITON...YEADON...CONSHOHOCKEN...HATBORO... FOLCROFT...AMBLER...SWARTHMORE...COLLEGEVILLE...ROYERSFORD... JENKINTOWN...NARBERTH...TRAPPE...EAST LANSDOWNE AND ROCKLEDGE. PRECAUTIONARY/PREPAREDNESS ACTIONS... SEVERE THUNDERSTORMS PRODUCE DAMAGING WINDS...LARGE HAIL...DEADLY LIGHTNING AND VERY HEAVY RAIN. FOR YOUR PROTECTION...MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF YOUR HOME OR BUSINESS. HEAVY RAINS FLOOD ROADS QUICKLY SO DO NOT DRIVE INTO AREAS WHERE WATER COVERS THE ROAD. THIS STORM HAS A HISTORY OF PRODUCING WIND DAMAGE. THIS IS A VERY DANGEROUS SITUATION. SEEK SHELTER NOW INSIDE A STURDY STRUCTURE AND STAY AWAY FROM WINDOWS. && LAT...LON 4041 7567 4011 7497 3986 7523 4007 7581 TIME...MOT...LOC 2037Z 290DEG 37KT 4013 7566 $$ SZATKOWSKI
1 follow-up statement
155 WWUS51 KPHI 092057 SVSPHI SEVERE WEATHER STATEMENT NATIONAL WEATHER SERVICE MOUNT HOLLY NJ 457 PM EDT FRI OCT 9 2015 PAC011-029-045-091-101-092130- /O.CON.KPHI.SV.W.0117.000000T0000Z-151009T2130Z/ CHESTER PA-BERKS PA-DELAWARE PA-MONTGOMERY PA-PHILADELPHIA PA- 457 PM EDT FRI OCT 9 2015 ...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 530 PM EDT FOR NORTHEASTERN CHESTER...SOUTHEASTERN BERKS...NORTHEASTERN DELAWARE...MONTGOMERY AND PHILADELPHIA COUNTIES... AT 456 PM EDT...DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM CAPABLE OF PRODUCING DAMAGING WINDS IN EXCESS OF 65 MPH. THIS STORM WAS LOCATED NEAR KING OF PRUSSIA...OR 12 MILES NORTHEAST OF WEST CHESTER...MOVING EAST AT 45 MPH. PENNY SIZE HAIL MAY ALSO ACCOMPANY THE DAMAGING WINDS. LOCATIONS IMPACTED INCLUDE... PHILADELPHIA...NORRISTOWN...POTTSTOWN...PHOENIXVILLE...LANSDALE... WEST NORRITON...EAST NORRITON...YEADON...CONSHOHOCKEN...HATBORO... FOLCROFT...AMBLER...SWARTHMORE...COLLEGEVILLE...ROYERSFORD... JENKINTOWN...NARBERTH...TRAPPE...EAST LANSDOWNE AND ROCKLEDGE. PRECAUTIONARY/PREPAREDNESS ACTIONS... SEVERE THUNDERSTORMS PRODUCE DAMAGING WINDS...DESTRUCTIVE HAIL... DEADLY LIGHTNING AND VERY HEAVY RAIN. FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF YOUR HOME OR BUSINESS. HEAVY RAINS FLOOD ROADS QUICKLY SO DO NOT DRIVE INTO AREAS WHERE WATER COVERS THE ROAD. THIS STORM HAS A HISTORY OF PRODUCING WIND DAMAGE. THIS IS A VERY DANGEROUS SITUATION. SEEK SHELTER NOW INSIDE A STURDY STRUCTURE AND STAY AWAY FROM WINDOWS. && LAT...LON 4041 7567 4011 7497 3986 7523 4007 7581 TIME...MOT...LOC 2056Z 290DEG 37KT 4006 7542 $$ SZATKOWSKI
The office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Oct 9, 2:45 PM EDT | Special Weather Statement | PHI | Berks, Carbon, Lehigh, Monroe, Northampton | 90 min |
| Oct 9, 3:17 PM EDT | Severe Thunderstorm Warning | PHI | Berks, Carbon, Lehigh, Monroe, Northampton | 58 min |
| Oct 9, 4:01 PM EDT | Severe Thunderstorm Warning | PHI | Berks, Chester | 44 min |
| Oct 9, 4:47 PM EDT | Tornado Warning | PHI | Chester, Montgomery | 28 min |
| Oct 9, 5:25 PM EDT | Special Weather Statement | PHI | Bucks, Montgomery | 65 min |
| Oct 9, 5:41 PM EDT | Special Weather Statement | PHI | Philadelphia | 49 min |
Nearby
Severe Thunderstorm Warnings in Pennsylvania, 2015Every severe thunderstorm warning in 2015
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.