Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2004
Severe Thunderstorm Warning 164, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Aug 11, 2004, 2:40 PM EDT for Chester County, Pennsylvania. It was in force for 95 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, 2004, 2:40 PM EDT (18:40 UTC)
- Expired
- Aug 11, 2004, 4:15 PM EDT
- In force
- 95 min
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Counties, with a storm outline in the text
County Chester County, PA
The radar
The Philadelphia radar (KDIX), 119 km from the middle of the area, began a volume at 18:40 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 watch it was issued in
The SPC watch in force over the same counties when this warning went out.
| Issued | Product | Office | Lasted |
|---|---|---|---|
| Aug 11, 12:55 PM EDT | Severe Thunderstorm Watch | SPC | 7 hr |
The nearest sounding before it
Washington/Dulle, VA (KIAD), launched 12:00Z, 6.7 hours before the alert went out and 173 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
- 253 J/kg
- Mixed-layer CIN
- -107 J/kg
- Mixed-layer LCL
- 1194 m above ground
- 0-6 km bulk shear
- 26 kt
- 0-1 km storm-relative helicity
- 51 m²/s²
- 0-3 km storm-relative helicity
- 95 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.2
The text
As transmitted, in the capitals the NWS used until 2016.
000
WUUS51 KPHI 111840
SVRPHI
PAC029-112015-
BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
239 PM EDT WED AUG 11 2004
THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A
* SEVERE THUNDERSTORM WARNING FOR...
CHESTER COUNTY IN SOUTHEAST PENNSYLVANIA.
* UNTIL 415 PM EDT
* AT 236 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL...AND
DESTRUCTIVE WINDS TO AROUND 65 MPH. THIS STORM WAS LOCATED 12
MILES NORTHWEST OF OXFORD AND MOVING EAST AT 20 MPH.
* GIVEN THE PRESENT MOTION THE SEVERE THUNDERSTORM WILL BE NEAR...
7 MILES NORTH OF OXFORD BY 305 PM EDT...
PARKESBURG BY 320 PM EDT...
WEST GROVE AND COATESVILLE BY 335 PM EDT...
KENNETT SQUARE BY 355 PM EDT...
7 MILES SOUTH OF DOWNINGTOWN BY 400 PM EDT...
WEST CHESTER BY 415 PM EDT...
LAT...LON 3986 7601 3987 7599 3992 7600 4001 7596
4008 7545 3999 7545 3987 7562 3985 7561
3983 7569 3978 7575 3978 7606
$$
TFGThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 11, 2:21 PM EDT | Severe Thunderstorm Warning | PHI | Bucks | 54 min |
| Aug 11, 3:12 PM EDT | Tornado Warning | PHI | Chester | 78 min |
| Aug 11, 4:04 PM EDT | Severe Thunderstorm Warning | PHI | Bucks | 41 min |
| Aug 11, 5:09 PM EDT | Special Marine Warning | PHI | 81 min | |
| Aug 11, 5:25 PM EDT | Severe Thunderstorm Warning | PHI | Berks | 65 min |
| Aug 11, 5:28 PM EDT | Severe Thunderstorm Warning | PHI | Philadelphia | 32 min |
| Aug 11, 5:37 PM EDT | Severe Thunderstorm Warning | PHI | Bucks | 53 min |
| Aug 11, 5:56 PM EDT | Severe Thunderstorm Warning | PHI | Montgomery | 34 min |
Nearby
Severe Thunderstorm Warnings in Pennsylvania, 2004Every severe thunderstorm warning in 2004
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.