Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2008
Severe Thunderstorm Warning 244, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Aug 11, 2008, 4:21 PM EDT for Montgomery County, Pennsylvania. It was in force for 39 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
- Aug 11, 2008, 4:21 PM EDT (20:21 UTC)
- Expired
- Aug 11, 2008, 5:00 PM EDT
- In force
- 39 min
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
County Montgomery County, PA
The radar
The Philadelphia radar (KDIX), 88 km from the middle of the area, began a volume at 20:23 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
Phillips Aaf/Abe, MD (KAPG), launched 12:00Z, 8.4 hours before the alert went out and 109 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
- 588 J/kg
- Mixed-layer CIN
- -38 J/kg
- Mixed-layer LCL
- 662 m above ground
- 0-6 km bulk shear
- 49 kt
- 0-1 km storm-relative helicity
- 6 m²/s²
- 0-3 km storm-relative helicity
- 20 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
000
WUUS51 KPHI 112021
SVRPHI
PAC091-112100-
/O.NEW.KPHI.SV.W.0244.080811T2021Z-080811T2100Z/
BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
421 PM EDT MON AUG 11 2008
THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A
* SEVERE THUNDERSTORM WARNING FOR...
CENTRAL MONTGOMERY COUNTY IN SOUTHEAST PENNSYLVANIA...
* UNTIL 500 PM EDT
* AT 419 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING PENNY SIZE HAIL AND
POSSIBLY SOME STRONG GUSTY WINDS. THIS STORM WAS LOCATED
6 MILES NORTHWEST OF SPRING MOUNT...OR ABOUT 16
MILES SOUTH OF ALLENTOWN...AND MOVING SOUTHEAST AT 29 MPH.
* THE SEVERE THUNDERSTORM WILL BE NEAR...
SPRING MOUNT BY 430 PM...
COLLEGEVILLE AND 9 MILES SOUTHWEST OF LANSDALE BY 445 PM...
LAT...LON 4039 7550 4022 7517 4021 7516 4021 7515
4009 7542 4034 7558
TIME...MOT...LOC 2021Z 337DEG 25KT 4034 7551
$$
TFG1 follow-up statement
000
WWUS51 KPHI 112046
SVSPHI
SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
446 PM EDT MON AUG 11 2008
PAC091-112100-
/O.CON.KPHI.SV.W.0244.000000T0000Z-080811T2100Z/
MONTGOMERY PA-
446 PM EDT MON AUG 11 2008
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 500 PM EDT
FOR CENTRAL MONTGOMERY COUNTY...
AT 441 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING PENNY SIZE HAIL
AND POSSIBLY STRONG GUSTY WINDS. THIS STORM WAS LOCATED NEAR
SCHWENKSVILLE...OR 19 MILES WEST OF WILLOW GROVE...MOVING
SOUTHEAST AT 26 MPH.
THE SEVERE THUNDERSTORM WILL BE NEAR...
WEST NORRITON...TROOPER...EAGLEVILLE AND EAST NORRITON BY 455 PM
EDT...
8 MILES SOUTHWEST OF SPRING HOUSE BY 500 PM EDT...
LAT...LON 4024 7552 4029 7541 4019 7522 4017 7523
4017 7525 4016 7526 4009 7542
TIME...MOT...LOC 2046Z 325DEG 23KT 4020 7543
$$
TFGThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 11, 9:00 AM EDT | Severe Thunderstorm Warning | PHI | Berks, Lehigh | 45 min |
| Aug 11, 11:23 AM EDT | Severe Thunderstorm Warning | PHI | Monroe | 38 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.