Alert archive / Pennsylvania / Tornado Warnings in 1999

Tornado Warning 4, NWS State College, PA

July 9, 1999Warren County, Pennsylvania

NWS State College, PA issued this tornado warning at Jul 9, 1999, 6:56 PM EDT for Warren County, Pennsylvania. It was in force for 49 min. No storm report in the archive falls 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.

The facts

Issued
Jul 9, 1999, 6:56 PM EDT (22:56 UTC)
Expired
Jul 9, 1999, 7:45 PM EDT
In force
49 min
Issued by
NWS State College, PA
Area
Whole counties; the outline is the Mesonet’s reconstruction

County Warren County, PA

The radar

The Buffalo radar (KBUF), 133 km from the middle of the area, began a volume at 22:55 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.

IssuedProductOfficeLasted
Jul 9, 6:45 PM EDTSevere Thunderstorm WatchSPC5 hr

The nearest sounding before it

Buffalo Intl Airport, NY (KBUF), launched 12:00Z, 10.9 hours before the alert went out and 132 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 1999-07-09Temperature 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 1999-07-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 211 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
1155 m above ground
0-6 km bulk shear
47 kt
0-1 km storm-relative helicity
211 m²/s²
0-3 km storm-relative helicity
519 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 092300 RRA
TORCTP
PAC123-092345-

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE STATE COLLEGE PA
656 PM EDT FRI JUL 9 1999

THE NATIONAL WEATHER SERVICE IN STATE COLLEGE PA HAS ISSUED A

* TORNADO WARNING FOR...
  WARREN COUNTY.

* UNTIL 745 PM EDT.

* AT 652 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  THUNDERSTORM WITH A DEVELOPING TORNADO 5 MILES NORTHWEST OF
  YOUNGSVILLE...OR ABOUT 13 MILES EAST OF CORRY...MOVING EAST AT 30
  MPH.

* THE TORNADO IS EXPECTED TO BE NEAR...
  WARREN AT 715 PM EDT.
  CLARENDON AT 725 PM EDT.

THIS TORNADO WARNING REPLACES THE SEVERE THUNDERSTORM WARNING WHICH
WAS IN EFFECT FOR THE SAME AREA. GO TO A BASEMENT OR SMALL INTERIOR
ROOM ON THE LOWEST FLOOR!

.END/ JUNG

LAT...LON 4195 7960 4168 7954 4169 7904 4197 7902

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 Jul 9, 1:45 PM EDT, 5 hours 11 minutes earlier.

Area forecast discussion, Jul 9, 1:45 PM EDT, 5 hours 11 minutes before
CENTRAL PENNSYLVANIA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
145 PM EDT FRI JUL 9 1999

SFC SW FLO CRANKING UP ATTM. FLO ALOFT ALREADY THERE PER VWP FM KCCX
AND KBUF. BEST DWPTS STILL IN OH...BUT ADVECTING NICELY ALOFT AND AT
SFC. MINI ECHOES ALREADY POPPED ALONG GOOD WAA BOUNDARY IN OUR NRN
FA. BUT THAT ACTIVITY IS RACING EAST WITH LLJ - >50KTS ON SPEED
THAT KIND OF CELL MOVEMENT DOESNT TAKE TOO MUCH MIXING TO PRODUCE
DAMAGE OUT OF A THUNDERSTORM.

THE OL SUMMER/DROUGHT OF 99 NO-RAIN SHAFT OF STATE COLLEGE APPEARS
AGAIN ON MODEL QPF PRODUCTS. THIS MAY BE MDLS PICKING UP ON WEAKER
INSTAB OV MTNS. ANYWAY...THE TREND IN MOST RECENT MDL RUNS IS TO PUT
LOWER POPS/QPF INTO CENTL MTNS AND LWR SUSQ.  MOSTLY CONSISTENT WITH
THINKING ATTM...BUT STILL BELIEVE THE MORE LIKELY SCENARIO IS A
SQULL LINE TO FORM AND DROP SEWD INTO MTNS...WEAKENING AS IT DOES
SO. MOST/ALL SVR ACTIVITY SHUD BE CONTAINED TO N&W OF IPT-UNV-AOO
LINE TONIGHT.  LATEST RUC POINTING TO START UP CONVECTION BY 21Z IN
NW PA...CONSISTENT WITH EARLIER THINKING.  POPS TONIGHT TO BE CAT IN
WRN ZNS/LIKELY IN CENTL&MID SUSQ AND CHC IN SE (MAINLY LATE).

AS THE SQUALL LINE WEAKENS...IT WL MOST LIKELY SPIT INTO TWO AREAS
OF CNVCTN - ONE DROPPING STRAIGHT SOUTH THROUGH THE LAURELS (FEEDING
OFF THE TERRIFIC THTE ADV AND LLJ FM SW)...AND ONE THAT GOES WITH
BEST WAA/UPR SUPPORT TWD ELM/BGM.  THE FNT DOES LOOK TO HANG UP AS
IT MOVES THRU OUR AREA...BUT REAL FNT AND NNW FLO DOES NOT MAKE IT
THRU FA UNTIL AFTER 12Z. THEREFORE CHC POPS WL REMAIN IN FAR SRN
ZNS...INCL THE LWR SUSQ...IN EARLY SAT PD. DRYING/MO SUN FOR REST OF
FA ON SAT AND COOLER/FAIR FOR SUN.

XTNDD: FRIENDLY HIGH PRES FOR BEGINNING OF WEEK. SLIGHT WARMING
TREND THRU XTNDD PD...AND CHC WORDING MAKES RETURN ON TUES FOR
EVERYONE AND WED AS WELL FOR ERN ZNS AS MRF DEVELOPS WAVE ALONG FNT
THAT HANGS UP IN SE US.  THE WAVE AND WAA RIDES THE RETURN FLOW OF
THE SFC HI AS IT MOVES OFF THE EAST COAST.

.CTP...NONE.

DANGELO

In the hours before

Special weather statement, Jul 9, 3:15 PM EDT, 3 hours 41 minutes before
PAZ004>006-010>012-017>019-024>028-033>035-037-041-042-045-046-
049>053-100400-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE STATE COLLEGE PA
315 PM EDT FRI JUL 9 1999

...THERE CONTINUES TO BE A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS
NORTHERN AND WEST-CENTRAL PENNSYLVANIA THIS EVENING AND TONIGHT...

WARM...HUMID AIR HAS MOVED INTO THE STATE FROM THE WEST THIS
AFTERNOON. THUNDERSTORMS HAVE ALREADY BEGUN TO POP UP IN THE UNSTABLE
AIR. AS THE EVENING CONTINUES...A COLD FRONT WILL APPROACH
PENNSYLVANIA FROM THE NORTHWEST. THE APPROACH OF THIS FRONT WILL
TRIGGER MORE SHOWERS AND THUNDERSTORMS. THE COMBINATION OF THE
WARM...HUMID AIR AT THE SURFACE AND THE FAST WINDS ALOFT WILL CREATE
THE POTENTIAL FOR DAMAGING WINDS TO COME OUT OF THE THUNDERSTORMS.

THE MOST LIKELY SCENARIO FOR THIS EVENING IS THAT A LONG LINE OF
THUNDERSTORMS WILL DEVELOP LATER THIS EVENING AND DROP TO THE
SOUTHEAST...INTO WESTERN PENNSYLVANIA AND THE CENTRAL MOUNTAINS
DURING THE NIGHT. THE SCATTERED THUNDERSTORMS ALREADY FORMING
LATE THIS AFTERNOON HAVE THE POTENTIAL TO PRODUCE DAMAGING WINDS...
LARGE HAIL AND EVEN TORNADOES. AGAIN...THE MAIN THREAT FOR THIS
EVENING WILL BE DAMAGING THUNDERSTORM WIND GUSTS.

PLEASE STAY TUNED TO YOUR NOAA WEATHER RADIO...A COMMERCIAL RADIO OR
YOUR CABLE TELEVISION SERVICE PROVIDER FOR LATER STATEMENTS AND
POSSIBLE SEVERE THUNDERSTORM WATCHES FROM THE NATIONAL WEATHER
SERVICE.

SKYWARN ACTIVATION WILL LIKELY BE NEEDED THIS EVENING.

.END/DANGELO
Special weather statement, Jul 9, 3:15 PM EDT, 3 hours 41 minutes before
PAZ004>006-010>012-017>019-024>028-033>035-037-041-042-045-046-
049>053-100400-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE STATE COLLEGE PA
315 PM EDT FRI JUL 9 1999

...THERE CONTINUES TO BE A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS
NORTHERN AND WEST-CENTRAL PENNSYLVANIA THIS EVENING AND TONIGHT...

WARM...HUMID AIR HAS MOVED INTO THE STATE FROM THE WEST THIS
AFTERNOON. THUNDERSTORMS HAVE ALREADY BEGUN TO POP UP IN THE UNSTABLE
AIR. AS THE EVENING CONTINUES...A COLD FRONT WILL APPROACH
PENNSYLVANIA FROM THE NORTHWEST. THE APPROACH OF THIS FRONT WILL
TRIGGER MORE SHOWERS AND THUNDERSTORMS. THE COMBINATION OF THE
WARM...HUMID AIR AT THE SURFACE AND THE FAST WINDS ALOFT WILL CREATE
THE POTENTIAL FOR DAMAGING WINDS TO COME OUT OF THE THUNDERSTORMS.

THE MOST LIKELY SCENARIO FOR THIS EVENING IS THAT A LONG LINE OF
THUNDERSTORMS WILL DEVELOP LATER THIS EVENING AND DROP TO THE
SOUTHEAST...INTO WESTERN PENNSYLVANIA AND THE CENTRAL MOUNTAINS
DURING THE NIGHT. THE SCATTERED THUNDERSTORMS ALREADY FORMING
LATE THIS AFTERNOON HAVE THE POTENTIAL TO PRODUCE DAMAGING WINDS...
LARGE HAIL AND EVEN TORNADOES. AGAIN...THE MAIN THREAT FOR THIS
EVENING WILL BE DAMAGING THUNDERSTORM WIND GUSTS.

PLEASE STAY TUNED TO YOUR NOAA WEATHER RADIO...A COMMERCIAL RADIO OR
YOUR CABLE TELEVISION SERVICE PROVIDER FOR LATER STATEMENTS AND
POSSIBLE SEVERE THUNDERSTORM WATCHES FROM THE NATIONAL WEATHER
SERVICE.

SKYWARN ACTIVATION WILL LIKELY BE NEEDED THIS EVENING.

.END/DANGELO
Local storm report, Jul 9, 5:04 PM EDT, 1 hour 52 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE STATE COLLEGE PA
504 PM EDT FRI JUL 09 1999

TIME(EDT)  .....CITY LOCATION..... STATE  ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0410 PM    BROCKPORT                 PA   WIND DAMAGE
07/09/99   ELK                            NUMEROUS TREES DOWN

0412 PM    RIDGWAY                   PA   WIND DAMAGE
07/09/99   ELK                            MANY TREES DOWN ON TOBY
                                          ROAD...IN FOX TOWNSHIP...6
                                          MILES SOUTH OF RIDGWAY.

0415 PM    RIDGWAY                   PA   1 INCH HAIL
07/09/99   ELK                            QUARTER SIZE HAIL 1 MILE
                                          SOUTH OF RIDGWAY...AT EMA
                                          OFFICE
Special weather statement, Jul 9, 5:20 PM EDT, 1 hour 36 minutes before
PAZ004-100300-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE STATE COLLEGE PA
520 PM EDT FRI JUL 9 1999

...A SEVERE THUNDERSTORM WATCH IS IN EFFECT UNTIL 11 PM FOR WARREN
COUNTY...

A COLD FRONT...ENTERING OHIO EARLY THIS EVENING...WILL PUSH INTO
PENNSYLVANIA OVERNIGHT.  THUNDERSTORMS WILL DEVELOP AHEAD OF THE
FRONT AND AFFECT MUCH OF WESTERN PENNSYLVANIA DURING THIS EVENING.
ANY STORMS THAT FORM WILL HAVE THE POTENTIAL TO PRODUCE STRONG
DAMAGING WINDS AND LARGE HAIL.

A SEVERE THUNDERSTORM WATCH MEANS THAT CONDITIONS ARE FAVORABLE FOR
SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH AREA. REMEMBER SEVERE
THUNDERSTORMS CAN SOMETIMES PRODUCE TORNADOES.

PLEASE STAY TUNED TO NOAA WEATHER RADIO...COMMERCIAL RADIO OR
TELEVISION STATIONS...OR YOUR CABLE TELEVISION SERVICE PROVIDER FOR
LATER STATEMENTS AND POSSIBLE WARNINGS.

.END/FITZGERALD
Special weather statement, Jul 9, 5:20 PM EDT, 1 hour 36 minutes before
PAZ004-100300-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE STATE COLLEGE PA
520 PM EDT FRI JUL 9 1999

...A SEVERE THUNDERSTORM WATCH IS IN EFFECT UNTIL 11 PM FOR WARREN
COUNTY...

A COLD FRONT...ENTERING OHIO EARLY THIS EVENING...WILL PUSH INTO
PENNSYLVANIA OVERNIGHT.  THUNDERSTORMS WILL DEVELOP AHEAD OF THE
FRONT AND AFFECT MUCH OF WESTERN PENNSYLVANIA DURING THIS EVENING.
ANY STORMS THAT FORM WILL HAVE THE POTENTIAL TO PRODUCE STRONG
DAMAGING WINDS AND LARGE HAIL.

A SEVERE THUNDERSTORM WATCH MEANS THAT CONDITIONS ARE FAVORABLE FOR
SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH AREA. REMEMBER SEVERE
THUNDERSTORMS CAN SOMETIMES PRODUCE TORNADOES.

PLEASE STAY TUNED TO NOAA WEATHER RADIO...COMMERCIAL RADIO OR
TELEVISION STATIONS...OR YOUR CABLE TELEVISION SERVICE PROVIDER FOR
LATER STATEMENTS AND POSSIBLE WARNINGS.

.END/FITZGERALD

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 9, 3:47 PM EDTSevere Thunderstorm WarningCTPElk58 min
Jul 9, 4:02 PM EDTTornado WarningCTPElk28 min
Jul 9, 4:25 PM EDTSevere Thunderstorm WarningCTPCameron, Clearfield65 min
Jul 9, 4:42 PM EDTSevere Thunderstorm WarningCTPCentre, Clinton63 min
Jul 9, 5:35 PM EDTSevere Thunderstorm WarningCTPCentre, Snyder, Union55 min
Jul 9, 6:39 PM EDTSevere Thunderstorm WarningCTPWarren66 min
Jul 9, 7:26 PM EDTSevere Thunderstorm WarningCTPMcKean64 min
Jul 9, 7:45 PM EDTSevere Thunderstorm WarningCTPWarren30 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.