Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 1998
Severe Thunderstorm Warning 5, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Apr 1, 1998, 2:23 PM 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 counties it named, with what was reported inside it.
The facts
- Issued
- Apr 1, 1998, 2:23 PM EST (19:23 UTC)
- Expired
- Apr 1, 1998, 2:55 PM EST
- In force
- 32 min
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Whole counties
County Chester County, PA
The radar
The Philadelphia radar (KDIX), 114 km from the middle of the area, began a volume at 19:27 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 |
|---|---|---|---|
| Apr 1, 2:37 PM EST | Tornado F1 | Cedarville, 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
Phillips Aaf/Abe, MD (KAPG), launched 12:00Z, 7.4 hours before the alert went out and 64 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
- 1059 m above ground
- 0-6 km bulk shear
- 28 kt
- 0-1 km storm-relative helicity
- 179 m²/s²
- 0-3 km storm-relative helicity
- 141 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
000 TTAA00 KPHL 011923 RRA SVRPHL PAC029-011955- BULLETIN - EAS ACTIVATION REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE MOUNT HOLLY NJ 223 PM EST WED APR 1 1998 THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 255 PM EST FOR PEOPLE IN THE FOLLOWING LOCATION... IN PENNSYLVANIA ...NORTHERN CHESTER COUNTY AT 220 PM EST... RADAR SHOWED A SEVERE THUNDERSTORM IN THE VICINITY OF HONEY BROOK MOVING EAST NORTHEAST AT 50 MPH. THIS STORM MAY AFFECT THE FOLLOWING NEARBY AREAS... KIMBERTON... DEVAULT... SPRING CITY... PHOENIXVILLE AND VALLEY FORGE. THIS IS A DANGEROUS STORM. MOVE INSIDE A STRONG BUILDING AND DO NOT STAND NEAR WINDOWS. FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF YOUR HOME OR BUSINESS. DO NOT DRIVE YOUR CAR WHERE WATER COVERS THE ROADWAY. THE WATER MAY BE DEEPER THAN YOU THINK. IF CAUGHT IN RISING FLOOD WATERS... ABANDON YOUR CAR QUICKLY AND MOVE TOt HIGHER GROUND. FOR THE LATEST STORM INFORMATION...PLEASE TUNE TO NOAA WEATHER RADIO...YOUR LOCAL RADIO OR TELEVISION STATIONS...OR YOUR CABLE TELEVISION OUTLET. MPD
The office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 1, 3:38 PM EST | Flash Flood Warning | PHI | Chester | 3 hr |
| Apr 1, 6:20 PM EST | Flash Flood Warning | PHI | Chester, Montgomery | 3 hr |
| Apr 1, 6:46 PM EST | Severe Thunderstorm Warning | PHI | Bucks | 34 min |
Nearby
Severe Thunderstorm Warnings in Pennsylvania, 1998Every severe thunderstorm warning in 1998
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.