Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2008
Severe Thunderstorm Warning 257, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Sep 9, 2008, 8:51 AM EDT for 7 counties in Pennsylvania. It was in force for 39 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
- Sep 9, 2008, 8:51 AM EDT (12:51 UTC)
- Expired
- Sep 9, 2008, 9:30 AM EDT
- In force
- 39 min
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
Counties Berks County, PA, Bucks County, PA, Carbon County, PA, Chester County, PA, Lehigh County, PA, Montgomery County, PA, Northampton County, PA
The radar
The Philadelphia radar (KDIX), 129 km from the middle of the area, began a volume at 12:53 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 |
|---|---|---|---|
| Sep 9, 8:54 AM EDT | TSTM WND GST 37 | Reading, PA | A 37 MPH WIND GUST WAS MEASURED AT THE READING AIRPORT. |
| Sep 9, 9:00 AM EDT | TSTM WND DMG | Reading, PA | MULTIPLE TREES DOWN IN BERKS COUNTY |
Local storm reports filed while the alert was in force, from inside its polygon or its counties.
The nearest sounding before it
Phillips Aaf/Abe, MD (KAPG), launched 12:00Z, 0.9 hours before the alert went out and 106 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
- 1988 J/kg
- Mixed-layer CIN
- -21 J/kg
- Mixed-layer LCL
- 557 m above ground
- 0-6 km bulk shear
- 39 kt
- 0-1 km storm-relative helicity
- 118 m²/s²
- 0-3 km storm-relative helicity
- 109 m²/s²
- Significant tornado parameter
- 1.0
- Supercell composite
- 5.3
The text
As transmitted, in the capitals the NWS used until 2016.
000
WUUS51 KPHI 091251
SVRPHI
PAC011-017-025-029-077-091-095-091330-
/O.NEW.KPHI.SV.W.0257.080909T1251Z-080909T1330Z/
BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
851 AM EDT TUE SEP 9 2008
THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A
* SEVERE THUNDERSTORM WARNING FOR...
BERKS COUNTY IN EASTERN PENNSYLVANIA...
LEHIGH COUNTY IN EASTERN PENNSYLVANIA...
SOUTHERN NORTHAMPTON COUNTY IN EASTERN PENNSYLVANIA...
EXTREME SOUTH CENTRAL CARBON COUNTY IN NORTHEAST PENNSYLVANIA...
NORTHWESTERN BUCKS COUNTY IN SOUTHEAST PENNSYLVANIA...
NORTH CENTRAL CHESTER COUNTY IN SOUTHEAST PENNSYLVANIA...
NORTHWESTERN MONTGOMERY COUNTY IN SOUTHEAST PENNSYLVANIA...
* UNTIL 930 AM EDT
* AT 849 AM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
A LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING DAMAGING WINDS
OF AROUND 60 MPH. THESE STORMS WERE LOCATED ALONG A LINE
EXTENDING FROM EMERALD TO 13 MILES WEST OF HONEY BROOK...OR
ALONG A LINE EXTENDING FROM 6 MILES SOUTH OF LEHIGHTON TO 11
MILES NORTHEAST OF LANCASTER...AND MOVING EAST AT ABOUT 35 MPH.
* SEVERE THUNDERSTORMS WILL BE NEAR...
EMERALD...READING...KUTZTOWN AND FLEETWOOD BY 855 AM...
BERLINSVILLE...NEFFS...CLAUSSVILLE AND SCHNECKSVILLE BY 900 AM...
BEERSVILLE AND NORTHAMPTON BY 910 AM...
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.
IN ADDITION TO HAIL AND DAMAGING WINDS...CONTINUOUS CLOUD TO GROUND
LIGHTNING IS OCCURRING WITH THESE STORM. MOVE INDOORS IMMEDIATELY
LIGHTNING IS ONE OF NATURES NUMBER ONE KILLERS. REMEMBER...IF YOU
CAN HEAR THUNDER...YOU ARE CLOSE ENOUGH TO BE STRUCK BY LIGHTNING.
LAT...LON 4071 7584 4075 7577 4083 7513 4001 7573
4003 7595 4010 7595 4014 7590 4031 7615
TIME...MOT...LOC 1250Z 277DEG 30KT 4074 7570 4014 7613
$$
MPDThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 9, 8:40 AM EDT | Severe Thunderstorm Warning | PHI | Carbon, Lehigh, Monroe, Northampton | 50 min |
| Sep 9, 8:51 AM EDT | Areal Flood Advisory | PHI | Berks, Lehigh | 3 hr |
| Sep 9, 9:09 AM EDT | Areal Flood Advisory | PHI | Northampton | 3 hr |
| Sep 9, 9:21 AM EDT | Severe Thunderstorm Warning | PHI | Berks, Bucks, Chester, Delaware, Lehigh, Monroe and 3 more | 39 min |
| Sep 9, 9:30 AM EDT | Flash Flood Warning | PHI | Chester, Montgomery | 3 hr |
| Sep 9, 9:41 AM EDT | Flash Flood Warning | PHI | Bucks | 3 hr |
| Sep 9, 9:59 AM EDT | Flash Flood Warning | PHI | Bucks, Delaware, Montgomery, Philadelphia | 3 hr |
| Sep 9, 10:57 AM EDT | Severe Thunderstorm Warning | PHI | Bucks | 48 min |
Nearby
Severe Thunderstorm Warnings in Pennsylvania, 2008Every severe thunderstorm warning in 2008
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.