Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2002
Severe Thunderstorm Warning 187, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Aug 24, 2002, 7:12 PM EDT for Berks County, Chester County, Montgomery County, Pennsylvania. It was in force for 33 min. 3 reports came from inside the area while it was in force.
The area
The counties it named, with what was reported inside it.
The facts
- Issued
- Aug 24, 2002, 7:12 PM EDT (23:12 UTC)
- Expired
- Aug 24, 2002, 7:45 PM EDT
- In force
- 33 min
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Whole counties
Counties Berks County, PA, Chester County, PA, Montgomery County, PA
The radar
The Philadelphia radar (KDIX), 112 km from the middle of the area, began a volume at 23:13 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 |
|---|---|---|---|
| Aug 24, 7:18 PM EDT | Thunderstorm Wind 52 E | Pottstown, PA | |
| Aug 24, 7:20 PM EDT | Thunderstorm Wind 52 E | Coatesville, PA | |
| Aug 24, 7:35 PM EDT | Thunderstorm Wind 52 E | Downingtown, PA |
NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.
The nearest sounding before it
Washington/Dulle, VA (KIAD), launched 12:00Z, 11.2 hours before the alert went out and 203 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
- 639 J/kg
- Mixed-layer CIN
- -37 J/kg
- Mixed-layer LCL
- 611 m above ground
- 0-6 km bulk shear
- 41 kt
- 0-1 km storm-relative helicity
- 14 m²/s²
- 0-3 km storm-relative helicity
- 94 m²/s²
- Significant tornado parameter
- 0.3
- Supercell composite
- 2.2
The office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 24, 6:56 PM EDT | Severe Thunderstorm Warning | PHI | Hunterdon, Warren | 34 min |
| Aug 24, 7:06 PM EDT | Severe Thunderstorm Warning | PHI | Camden | 24 min |
| Aug 24, 7:26 PM EDT | Severe Thunderstorm Warning | PHI | Burlington | 34 min |
| Aug 24, 7:32 PM EDT | Severe Thunderstorm Warning | PHI | Hunterdon, Somerset | 28 min |
| Aug 24, 7:36 PM EDT | Severe Thunderstorm Warning | PHI | Camden | 24 min |
| Aug 24, 7:52 PM EDT | Severe Thunderstorm Warning | PHI | Mercer | 38 min |
| Aug 24, 7:42 PM EDT | Severe Thunderstorm Warning | PHI | Chester, Delaware | 33 min |
| Aug 24, 7:44 PM EDT | Severe Thunderstorm Warning | PHI | Montgomery, Philadelphia | 46 min |
Nearby
Severe Thunderstorm Warnings in Pennsylvania, 2002Every severe thunderstorm warning in 2002
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.