Alert archive / Pennsylvania / Tornado Warnings in 1999

Tornado Warning 11, NWS State College, PA

October 13, 1999Potter County, Pennsylvania

NWS State College, PA issued this tornado warning at Oct 13, 1999, 7:42 PM EDT for Potter County, Pennsylvania. It was in force for 33 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
Oct 13, 1999, 7:42 PM EDT (23:42 UTC)
Expired
Oct 13, 1999, 8:15 PM EDT
In force
33 min
Issued by
NWS State College, PA
Area
Whole counties; the outline is the Mesonet’s reconstruction

County Potter County, PA

What was reported inside it

TimeReportWhereRemark
Oct 13, 7:46 PM EDTThunderstorm WindAustin, PATrees down.

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.

IssuedProductOfficeLasted
Oct 13, 6:45 PM EDTSevere Thunderstorm WatchSPC6 hr

The nearest sounding before it

Buffalo Intl Airport, NY (KBUF), launched 12:00Z, 11.7 hours before the alert went out and 154 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.

Skew-T log-pSkew-T log-p diagram, Buffalo Intl Airport, NY at 12:00Z on 1999-10-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Buffalo Intl Airport, NY at 12:00Z on 1999-10-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 237 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1328 m above ground
0-6 km bulk shear
41 kt
0-1 km storm-relative helicity
237 m²/s²
0-3 km storm-relative helicity
256 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
TTAA00 KCTP 132344 RRA
TORCTP
PAC105-140015-

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE STATE COLLEGE PA
742 PM EDT WED OCT 13 1999

THE NATIONAL WEATHER SERVICE IN STATE COLLEGE PA HAS ISSUED A

* TORNADO WARNING FOR...
  CENTRAL POTTER COUNTY.

* UNTIL 815 PM EDT.

* AT 741 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  THUNDERSTORM WITH A DEVELOPING TORNADO 21 MILES WEST OF GALETON...
  OR ABOUT 31 MILES NORTHEAST OF ST. MARYS...MOVING EAST AT 45 MPH.

* THE TORNADO IS EXPECTED TO BE NEAR...
  GALETON AT 805 PM EDT.

GO TO A BASEMENT OR A SMALL INTERIOR ROOM ON THE LOWEST FLOOR.

.END/ LA CORTE

LAT...LON 4170 7820 4162 7821 4156 7812 4157 7763
          418`6 7765

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 State College, PA wrote its last area forecast discussion before this tornado warning went out at Oct 13, 3:15 PM EDT, 4 hours 27 minutes earlier.

Area forecast discussion, Oct 13, 3:15 PM EDT, 4 hours 27 minutes before
CENTRAL PENNSYLVANIA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
315 PM EDT WED OCT 13 1999

HARDLY ANYTHING IN THE WAY OF SCT CONVECTION AHEAD OF LINE AS OF
YET...BUT VIS SAT LOOP SHOWS HORIZONTAL ROLLS ACROSS W PA...AND SOME
SCT SHRA/-TSRA MAY YET POP UP HERE B4 SUNSET. COMPOSITE RADAR LOOP
SHOWS LINE OF CONVECTION FILLING IN AS IT CROSSES LAKE ERIE. LOOKING
FURTHER UPSTREAM...I SEE SFC WINDS BEHIND COLD FRONT DO NOT LOOK TOO
IMPRESSIVE...WITH STRONGEST WINDS IN WAA AHEAD OF FRONT.

CONVECTION WILL BE MAIN THREAT TO PRODUCE STRONG WINDS THIS AFT/EVE.
BIGGEST THREAT WILL BE ACROSS NW CTP CWA LATE AFT/ERLY EVE AS LINE
MOVES THRU. THIS EVENT MAY HAVE AN ANOLOG WITH 30 SEPT 1999...WHERE
NARROW STRIPE OF CONVECTION BROUGHT WIDESPREAD WIND EVENT TO CWA.
850 MB WINDS SIMILAR IN BOTH CASES. SO TO COVER THE POTENTIAL THIS
TIME...HAVE HOISTED HI WIND WATCH FOR ENTIRE CWA. I THINK THE BEST
CHC WILL BE ACROSS N TIER WHERE DYNAMICS MOST FAVORABLE FOR
MAINTENANCE OF LINE AFTER SUN GOES DOWN.

RAIN TAPERING TO SHOWERS OVERNIGHT...AND I AGREE WITH BGM THINKING
ON CHC POPS NE PA ON THU MORNING.

EXTENDED...UKMET...EURO...AND MRF ALL TAKING TROPICAL MOISTURE FROM
IRENE UP THE EAST COAST AHEAD OF SHARPLY AMPLIFYNG CENTRAL US TROF.
MONDAY LOOKING PRETTY WET...ESP E PA.

.CTP...HIGH WIND WATCH ALL ZONES.

OSTUNO

In the hours before

Special weather statement, Oct 13, 3:49 PM EDT, 3 hours 53 minutes before
PAZ004-005-010-140200-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE STATE COLLEGE PA
349 PM EDT WED OCT 13 1999

...A SEVERE THUNDERSTORM WATCH HAS BEEN ISSUED MUCH OF FAR WESTERN
PENNSYLVANIA...

THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM WATCH
VALID UNTIL 10 PM EDT FOR FAR WESTERN PARTS OF PENNSYLVANIA.
THE WATCH IS IN EFFECT FOR THE FOLLOWING COUNTIES IN OF WEST CENTRAL
PENNSYLVANIA...

WARREN...MCKEAN...AND ELK.

AN AREA OF THUNDERSTORMS WILL CROSS EASTERN OHIO LATE THIS
AFTERNOON AND REACH WARREN...ELK AND MCKEAN COUNTIES AROUND SUNSET.
THE STORMS ARE MOVING QUITE RAPIDLY...AND THE GREATEST THREAT IS FROM
STRONG DAMAGING WINDS AS THEY REACH OUR AREA.

IF YOU ARE IN THE WATCH AREA SHOULD REMAIN ALERT FOR THE POTENTIAL OF
SEVERE WEATHER LATE THIS AFTERNOON AND THIS EVENING. STAY TUNED
TO NOAA WEATHER RADIO...THE OFFICIAL VOICE OF THE NATIONAL WEATHER
SERVICE...OR YOUR FAVORITE TELEVISION OR COMMERCIAL RADIO NEWS
SOURCE FOR LATER STATEMENTS AND FORECASTS.

.END/ DANGELO

ADDITIONAL WEATHER INFORMATION CAN BE FOUND ON THE WORLD WIDE WEB AT:

HTTP://BOOKEND.MET.PSU.EDU (ALL LOWER CASE)
Special weather statement, Oct 13, 3:49 PM EDT, 3 hours 53 minutes before
PAZ004-005-010-140200-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE STATE COLLEGE PA
349 PM EDT WED OCT 13 1999

...A SEVERE THUNDERSTORM WATCH HAS BEEN ISSUED MUCH OF FAR WESTERN
PENNSYLVANIA...

THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM WATCH
VALID UNTIL 10 PM EDT FOR FAR WESTERN PARTS OF PENNSYLVANIA.
THE WATCH IS IN EFFECT FOR THE FOLLOWING COUNTIES IN OF WEST CENTRAL
PENNSYLVANIA...

WARREN...MCKEAN...AND ELK.

AN AREA OF THUNDERSTORMS WILL CROSS EASTERN OHIO LATE THIS
AFTERNOON AND REACH WARREN...ELK AND MCKEAN COUNTIES AROUND SUNSET.
THE STORMS ARE MOVING QUITE RAPIDLY...AND THE GREATEST THREAT IS FROM
STRONG DAMAGING WINDS AS THEY REACH OUR AREA.

IF YOU ARE IN THE WATCH AREA SHOULD REMAIN ALERT FOR THE POTENTIAL OF
SEVERE WEATHER LATE THIS AFTERNOON AND THIS EVENING. STAY TUNED
TO NOAA WEATHER RADIO...THE OFFICIAL VOICE OF THE NATIONAL WEATHER
SERVICE...OR YOUR FAVORITE TELEVISION OR COMMERCIAL RADIO NEWS
SOURCE FOR LATER STATEMENTS AND FORECASTS.

.END/ DANGELO

ADDITIONAL WEATHER INFORMATION CAN BE FOUND ON THE WORLD WIDE WEB AT:

HTTP://BOOKEND.MET.PSU.EDU (ALL LOWER CASE)
Special weather statement, Oct 13, 7:10 PM EDT, 32 minutes before
PAZ006-011-012-017>019-024>028-033>037-041-042-045-046-049>053-
056>059-063>066-140500-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE STATE COLLEGE PA
710 PM EDT WED OCT 13 1999

...A SEVERE THUNDERSTORM WATCH HAS BEEN ISSUED FOR ALL OF CENTRAL
PENNSYLVANIA AND THE SUSQUEHANNA VALLEY.

THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM WATCH
VALID UNTIL 1 AM EDT FOR ALL OF CENTRAL PENNSYLVANIA AND THE
SUSQUEHANNA VALLEY. THE WATCH IS IN EFFECT FOR THE FOLLOWING
COUNTIES...

ADAMS...BEDFORD...BLAIR...CAMBRIA...CAMERON...CENTRE...CLEARFIELD...
CLINTON...COLUMBIA...CUMBERLAND...DAUPHIN...FRANKLIN...FULTON...
HUNTINGDON...JUNIATA...LANCASTER...LEBANON...LYCOMING...MIFFLIN...
MONTOUR...NORTHUMBERLAND...PERRY...POTTER...SCHUYLKILL...SNYDER...
SOMERSET...SULLIVAN...TIOGA...UNION....YORK.

AN AREA OF THUNDERSTORMS MOVING ACROSS WESTERN PENNSYLVANIA WILL
CROSS CENTRAL PENNSYLVANIA EARLY TONIGHT AND MOVE INTO THE
SUSQUEHANNA VALLEY AFTER 9 PM. THE STORMS ARE MOVING QUITE RAPIDLY...
AND THE GREATEST THREAT IS FROM STRONG DAMAGING WINDS AS THEY REACH
OUR AREA. LARGE HAIL IS ALSO POSSIBLE WITH THESE STORMS.

IF YOU ARE IN THE WATCH AREA REMAIN ALERT FOR THE POTENTIAL OF
SEVERE WEATHER THROUGH LATE TONIGHT. STAY TUNED TO NOAA WEATHER
RADIO...THE OFFICIAL VOICE OF THE NATIONAL WEATHER SERVICE...OR YOUR
FAVORITE TELEVISION OR COMMERCIAL RADIO NEWS SOURCE FOR LATER
STATEMENTS AND FORECASTS.

.END/ GARTNER

ADDITIONAL WEATHER INFORMATION CAN BE FOUND ON THE WORLD WIDE WEB AT:

HTTP://BOOKEND.MET.PSU.EDU (ALL LOWER CASE)
Special weather statement, Oct 13, 7:10 PM EDT, 32 minutes before
PAZ006-011-012-017>019-024>028-033>037-041-042-045-046-049>053-
056>059-063>066-140500-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE STATE COLLEGE PA
710 PM EDT WED OCT 13 1999

...A SEVERE THUNDERSTORM WATCH HAS BEEN ISSUED FOR ALL OF CENTRAL
PENNSYLVANIA AND THE SUSQUEHANNA VALLEY.

THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM WATCH
VALID UNTIL 1 AM EDT FOR ALL OF CENTRAL PENNSYLVANIA AND THE
SUSQUEHANNA VALLEY. THE WATCH IS IN EFFECT FOR THE FOLLOWING
COUNTIES...

ADAMS...BEDFORD...BLAIR...CAMBRIA...CAMERON...CENTRE...CLEARFIELD...
CLINTON...COLUMBIA...CUMBERLAND...DAUPHIN...FRANKLIN...FULTON...
HUNTINGDON...JUNIATA...LANCASTER...LEBANON...LYCOMING...MIFFLIN...
MONTOUR...NORTHUMBERLAND...PERRY...POTTER...SCHUYLKILL...SNYDER...
SOMERSET...SULLIVAN...TIOGA...UNION....YORK.

AN AREA OF THUNDERSTORMS MOVING ACROSS WESTERN PENNSYLVANIA WILL
CROSS CENTRAL PENNSYLVANIA EARLY TONIGHT AND MOVE INTO THE
SUSQUEHANNA VALLEY AFTER 9 PM. THE STORMS ARE MOVING QUITE RAPIDLY...
AND THE GREATEST THREAT IS FROM STRONG DAMAGING WINDS AS THEY REACH
OUR AREA. LARGE HAIL IS ALSO POSSIBLE WITH THESE STORMS.

IF YOU ARE IN THE WATCH AREA REMAIN ALERT FOR THE POTENTIAL OF
SEVERE WEATHER THROUGH LATE TONIGHT. STAY TUNED TO NOAA WEATHER
RADIO...THE OFFICIAL VOICE OF THE NATIONAL WEATHER SERVICE...OR YOUR
FAVORITE TELEVISION OR COMMERCIAL RADIO NEWS SOURCE FOR LATER
STATEMENTS AND FORECASTS.

.END/ GARTNER

ADDITIONAL WEATHER INFORMATION CAN BE FOUND ON THE WORLD WIDE WEB AT:

HTTP://BOOKEND.MET.PSU.EDU (ALL LOWER CASE)

The office that day

Everything else NWS State College, PA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Oct 13, 6:18 PM EDTSevere Thunderstorm WarningCTPWarren72 min
Oct 13, 6:19 PM EDTSevere Thunderstorm WarningCTPMcKean41 min
Oct 13, 6:42 PM EDTSevere Thunderstorm WarningCTPElk33 min
Oct 13, 7:05 PM EDTSevere Thunderstorm WarningCTPElk, McKean55 min
Oct 13, 7:14 PM EDTSevere Thunderstorm WarningCTPCameron61 min
Oct 13, 7:20 PM EDTTornado WarningCTPCameron25 min
Oct 13, 7:29 PM EDTSevere Thunderstorm WarningCTPPotter61 min
Oct 13, 7:52 PM EDTSevere Thunderstorm WarningCTPClearfield53 min

Nearby

Tornado Warnings in Pennsylvania, 1999Every tornado warning in 1999Tornadoes in 1999

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.