Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2000
Severe Thunderstorm Warning 129, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Dec 17, 2000, 6:13 AM EST for Chester County, Pennsylvania. It was in force for 32 min. 1 report came from inside the area while it was in force.
The area
The outline the Iowa Environmental Mesonet reconstructed for it; the warning itself named whole counties, with what was reported inside it.
The facts
- Issued
- Dec 17, 2000, 6:13 AM EST (11:13 UTC)
- Expired
- Dec 17, 2000, 6:45 AM EST
- In force
- 32 min
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Whole counties; the outline is the Mesonet’s reconstruction
County Chester County, PA
The radar
The Philadelphia radar (KDIX), 124 km from the middle of the area, began a volume at 11:14 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 |
|---|---|---|---|
| Dec 17, 6:15 AM EST | Thunderstorm Wind 50 E | Countywide, 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 watch it was issued in
The SPC watch in force over the same counties when this warning went out.
| Issued | Product | Office | Lasted |
|---|---|---|---|
| Dec 17, 2:15 AM EST | Tornado Watch | SPC | 5 hr |
The nearest sounding before it
Washington/Dulle, VA (KIAD), launched 00:00Z, 11.2 hours before the alert went out and 171 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 393 m above ground
- 0-6 km bulk shear
- 55 kt
- 0-1 km storm-relative helicity
- 329 m²/s²
- 0-3 km storm-relative helicity
- 348 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.3
The text
As transmitted, in the capitals the NWS used until 2016.
000 WUUS51 KPHI 171113 SVRPHL PAC029-171145- BULLETIN - EAS ACTIVATION REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE MOUNT HOLLY NJ 613 AM EST SUN DEC 17 2000 THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A * SEVERE THUNDERSTORM WARNING FOR... CHESTER COUNTY IN SOUTHEAST PENNSYLVANIA. * UNTIL 645 AM EST. * AT 604 AM EST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM... OVER OXFORD...MOVING NORTHEAST AT 75 MPH. * THE SEVERE THUNDERSTORM WILL BE NEAR... DOWNINGTOWN...WEST CHESTER AT 620 AM. LIONVILLE...PAOLI AT 625 AM. DAMAGING WINDS IN EXCESS OF 55 MPH ARE EXPECTED FROM THIS STORM. SEEK SHELTER IN A STURDY STRUCTURE UNTIL THE STORM HAS PASSED. THIS STORM IS CAPABLE OF PRODUCING HEAVY RAINFALL...WHICH MAY FLOOD LOW LYING AREAS SUCH AS DITCHES AND UNDERPASSES. AVOID THESE AREAS AND DO NOT CROSS FLOODED ROADS AS THEY MAY BE WASHED OUT. FOR THE LATEST STORM INFORMATION...PLEASE TUNE TO NOAA WEATHER RADIO...YOUR LOCAL RADIO OR TELEVISION STATION...OR YOUR CABLE TELEVISION OUTLET. LAT...LON 3980 7612 3975 7589 4006 7544 4021 7575
The office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Dec 17, 6:06 AM EST | Flash Flood Warning | PHI | Chester | 114 min |
| Dec 17, 6:50 AM EST | Flash Flood Warning | PHI | Bucks, Montgomery | 3 hr |
| Dec 17, 7:03 AM EST | Flash Flood Warning | PHI | Chester | 3 hr |
| Dec 17, 7:29 AM EST | Flash Flood Warning | PHI | Delaware | 3 hr |
| Dec 17, 9:33 AM EST | Flash Flood Warning | PHI | Chester | 117 min |
| Dec 17, 9:52 AM EST | Flash Flood Warning | PHI | Carbon, Monroe | 3 hr |
| Dec 17, 10:00 AM EST | Flash Flood Warning | PHI | Chester | 3 hr |
| Dec 17, 10:00 AM EST | Flash Flood Warning | PHI | Delaware | 3 hr |
Nearby
Severe Thunderstorm Warnings in Pennsylvania, 2000Every severe thunderstorm warning in 2000
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.