Alert archive / Pennsylvania / Tornado Warnings in 1998
Tornado Warning 13, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this tornado warning at Sep 2, 1998, 6:46 PM EDT for Chester County, Pennsylvania. It was in force for 34 min. 2 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
- Sep 2, 1998, 6:46 PM EDT (22:46 UTC)
- Expired
- Sep 2, 1998, 7:20 PM EDT
- In force
- 34 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 22:49 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 |
|---|---|---|---|
| Sep 2, 7:00 PM EDT | Thunderstorm Wind 50 | Westtown, PA | |
| Sep 2, 7:00 PM EDT | Hail 1 | Westtown, 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, 10.8 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
- 1665 m above ground
- 0-6 km bulk shear
- 32 kt
- 0-1 km storm-relative helicity
- 74 m²/s²
- 0-3 km storm-relative helicity
- 157 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.5
The text
As transmitted, in the capitals the NWS used until 2016.
215 WFUS1 KPHL 022246 RRA TORPHL PAC029-022320- BULLETIN - EAS ACTIVATION REQUESTED TORNADO WARNING NATIONAL WEATHER SERVICE MOUNT HOLLY NJ 646 PM EDT WED SEP 2 1998 THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A * TORNADO WARNING FOR... CHESTER COUNTY IN PENNSYLVANIA * UNTIL 720 PM EDT * AT 645 PM EDT... A TORNADO WAS INDICATED 5 MILES WEST OF WEST CHESTER... BY NATIONAL WEATHER SERVICE DOPPLER RADAR... MOVING EAST SOUTHEAST 20 MPH. * THE TORNADO IS EXPECTED TO BE NEAR... WEST CHESTER AT 700 PM EDT DO NOT TRY TO OUTRUN THIS TORNADO WITH YOUR CAR OR OTHER VEHICLE. ABANDON CARS OR MOBILE HOMES FOR SHELTER IN A NEARBY REINFORCED BUILDING. AS A LAST RESORT...GET IN A CULVERT OR DITCH AND COVER YOUR HEAD WITH YOUR HANDS. IN A HOME OR BUSINESS...SEEK SHELTER IN A BASEMENT...OR AN INTERIOR ROOM ON THE LOWEST FLOOR POSSIBLE. STAY AWAY FROM WINDOWS. FOR THE LATEST STORM INFORMATION...PLEASE TUNE TO NOAA WEATHER RADIO...YOUR LOCAL RADIO OR TELEVISION STATIONS...OR YOUR CABLE TELEVISION OUTLET. MD/RPW
What forecasters said that day
The local office's own words before this tornado warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Philadelphia/Mount Holly wrote its last area forecast discussion before this tornado warning went out at Sep 2, 3:15 PM EDT, 3 hours 31 minutes earlier.
Area forecast discussion, Sep 2, 3:15 PM EDT, 3 hours 31 minutes before
CENTRAL PENNSYLVANIA FORECAST DISCUSSION NATIONAL WEATHER SERVICE STATE COLLEGE PA 315 PM EDT WED SEP 2 1998 ...WRK ZNS FOR PHL/PIT SENT AT 245 PM ...LEFT SVR TSTM WATCH IN ZONES FOR LOWER/MID SUSQ THIS EVE (FIGURE BY THE TIME THESE ZONES ARE SENT...SVR THREAT WILL HAVE ENDED FOR ALL AREAS TO THE WEST)... ACTIVE COLD FRONT SLIDING ACROSS CENTRAL PA WITH LINE OF SHOWERS AND THUNDERSTORMS ALONG FRONT ATTM. AN ISOL SVR CELL POPED ACROSS N LANCASTER EARLIER PRODUCING 1/2 INCH HAIL. NO SVR YET ALONG LINE. EXPECT ADDITIONAL SVR CELLS TO POP IN THE LOWER/MID SUSQUHANNA WHERE DEWPTS HAVE RISEN INTO THE UPPER 60S AND DECENT SE INFLOW HAS DEVELOPED. WITH THE PASSAGE OF THE FRONT...CLEARING SKIES SHOULD OCCUR AND FOR THOSE AREAS THAT CLEAR COMPLETLY EXPECT SOME PATCHY FOG TO DEVELOP. ANOTHER SHRTWV SLIDES E ACROSS FCST/A ON THU WITH DECENT PV LOBE SHOWING UP AT 3H. RH PROGS SUGGEST COLD AIR STRATO-CU SHOULD HUG THE N TIER COUNTIES. WITH COLD 5H TEMPS AND CYCLONIC FLOW DECIDED TO KEEP SPRINKLES IN FCST ALONG N BORDER. WENT WITH MOSTLY CLOUDY SKIES NORTH/PTLY SUNNY SOUTH. YET ANOTHER SHRTWV TO SLIDE INTO FCST/A FOR LATE THU AND EARLY FRIDAY AS 80+ 3H JET STREAK (LF QUAD) APPROACHES AREA. INTRO 30 POPS AFTER MIDNIGHT FOR MOST AREAS. COLD FRONT TO SLIDE ACROSS REGION ON FRIDAY SO CONTINUED CHC POPS ACROSS FCST/A FOR MUCH OF FRIDAY. .CTP...SEVERE THUNDERSTORM WATCH FOR E CWA UNTIL 8 PM EDT. WINTHER J
In the hours before
Special weather statement, Sep 2, 3:45 PM EDT, 3 hours 1 minute before
PAZ006-011-012-017>019-024>028-033>037-041-042-045-046-049>053- 056>059-063>066-022345- SPECIAL WEATHER STATEMENT- SEVERE THUNDERSTORM WATCH NATIONAL WEATHER SERVICE STATE COLLEGE PA 345 PM EDT WED SEP 2 1998 ...THE SEVERE THUNDERSTORM WATCH THAT WAS IN EFFECT FOR PORTIONS OF THE CENTRAL AND SOUTHERN MOUNTAINS HAS BEEN CANCELED... THE SEVERE THUNDERSTORM WATCH IS NO LONGER IN EFFECT FOR THE FOLLOWING COUNTIES... TIOGA... NORTHERN LYCOMING... NORTHERN CLINTON... SULLIVAN... POTTER... CENTRE... BLAIR... HUNTINGDON... MIFFLIN... JUNIATA... BEDFORD...FULTON... FRANKLIN... THE SEVERE THUNDERSTORM WATCH CONTINUES UNTIL 8PM FOR THE FOLLOWING COUNTIES... SOUTHERN CLINTON... SNYDER... UNION...NORTHUMBERLAND... MONTOUR... COLUMBIA... SCHUYLKILL... ... PERRY... DAUPHIN... CUMBERLAND... LEBANON...ADAMS... YORK AND LANCASTER A LINE OF SHOWERS AND THUNDERSTORMS AHEAD OF A COLD FRONT WILL CONTINUE TO MOVE SOUTHEAST ACROSS THE WATCH AREA. SOME OF THE THUNDERSTORMS MAY CAUSE LOCALLY DAMAGING WINDS AND LARGE HAIL. KEEP TUNED TO NOAA WEATHER RADIO OR YOUR FAVORITE SOURCE OF NATIONAL WEATHER SERVICE INFORMATION VIA THE RADIO OR TELEVISION FOR ADDITIONAL UPDATES AND POSSIBLE WARNINGS. TAKE COVER INDOORS...PREFERABLY IN AN INTERIOR ROOM ON THE LOWEST FLOOR OF YOUR HOME OR BUSINESS...IF SEVERE WEATHER IS SIGHTED OR A WARNING IS ISSUED. LA CORTE
Special weather statement, Sep 2, 5:40 PM EDT, 1 hour 6 minutes before
PAZ006-011-012-017>019-024>028-033>037-041-042-045-046-049>053- 056>059-063>066-022345- SPECIAL WEATHER STATEMENT- SEVERE THUNDERSTORM WATCH NATIONAL WEATHER SERVICE STATE COLLEGE PA 540 PM EDT WED SEP 2 1998 ...THE SEVERE THUNDERSTORM WATCH THAT WAS IN EFFECT FOR PORTIONS OF THE MIDDLE SUSQUEHANNA VALLEY HAS BEEN CANCELED... THE SEVERE THUNDERSTORM WATCH IS NO LONGER IN EFFECT FOR THE FOLLOWING COUNTIES... SOUTHERN CLINTON... SOUTHERN LYCOMING... SNYDER... UNION... NORTHUMBERLAND... MONTOUR... COLUMBIA... AND SCHUYLKILL... THE SEVERE THUNDERSTORM WATCH CONTINUES UNTIL 8PM FOR THE FOLLOWING COUNTIES... ... PERRY... DAUPHIN... CUMBERLAND... LEBANON...ADAMS... YORK AND LANCASTER A LINE OF SHOWERS AND THUNDERSTORMS AHEAD OF A COLD FRONT WILL CONTINUE TO MOVE SOUTHEAST ACROSS THE WATCH AREA. SOME OF THE THUNDERSTORMS MAY CAUSE LOCALLY DAMAGING WINDS AND LARGE HAIL. IF SEVERE WEATHER IS SIGHTED OR A WARNING IS ISSUED...TAKE COVER INDOORS...PREFERABLY IN AN INTERIOR ROOM ON THE LOWEST FLOOR OF YOUR HOME OR BUSINESS. STAY TUNED TO NOAA WEATHER RADIO OR YOUR FAVORITE SOURCE OF NATIONAL WEATHER SERVICE INFORMATION VIA THE RADIO OR TELEVISION FOR ADDITIONALR UPDATES AND POSSIBLE WARNINGS. LA CORTE
The office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 2, 5:20 PM EDT | Severe Thunderstorm Warning | PHI | Carbon | 35 min |
| Sep 2, 5:39 PM EDT | Severe Thunderstorm Warning | PHI | Northampton | 46 min |
| Sep 2, 7:01 PM EDT | Tornado Warning | PHI | Delaware | 34 min |
Nearby
Tornado Warnings in Pennsylvania, 1998Every tornado warning in 1998Tornadoes 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.