Alert archive / Pennsylvania / Tornado Watches in 2003

Tornado Watch 358

May 11, 200320 counties in New York; 30 counties in Pennsylvania

The Storm Prediction Center issued this tornado watch at May 11, 2003, 1:50 PM EDT for 20 counties in New York; 30 counties in Pennsylvania. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued
May 11, 2003, 1:50 PM EDT (17:50 UTC)
Expired
May 11, 2003, 7:00 PM EDT
In force
5 hr
Issued by
the Storm Prediction Center
All 50 counties

Broome County, NY, Cayuga County, NY, Chemung County, NY, Chenango County, NY, Cortland County, NY, Herkimer County, NY, Jefferson County, NY, Lewis County, NY, Madison County, NY, Oneida County, NY, Onondaga County, NY, Ontario County, NY, Oswego County, NY, Schuyler County, NY, Seneca County, NY, Steuben County, NY, Tioga County, NY, Tompkins County, NY, Wayne County, NY, Yates County, NY, Adams County, PA, Bedford County, PA, Blair County, PA, Bradford County, PA, Centre County, PA, Clinton County, PA, Columbia County, PA, Cumberland County, PA, Dauphin County, PA, Franklin County, PA, Fulton County, PA, Huntingdon County, PA, Juniata County, PA, Lancaster County, PA, Lebanon County, PA, Luzerne County, PA, Lycoming County, PA, Mifflin County, PA, Montour County, PA, Northumberland County, PA, Perry County, PA, Potter County, PA, Schuylkill County, PA, Snyder County, PA, Sullivan County, PA, Susquehanna County, PA, Tioga County, PA, Union County, PA, Wyoming County, PA, York County, PA

The radar

The State College radar (KCCX), 98 km from the middle of the area, began a volume at 17:52 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.

Warnings issued inside it

17 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
May 11, 3:36 PM EDTSevere Thunderstorm WarningCTPClinton, Lycoming54 min
May 11, 3:49 PM EDTTornado WarningCTPLycoming41 min
May 11, 4:30 PM EDTSevere Thunderstorm WarningCTPLycoming15 min
May 11, 4:31 PM EDTSevere Thunderstorm WarningBUFOswego59 min
May 11, 4:42 PM EDTSevere Thunderstorm WarningBGMCortland, Tompkins48 min
May 11, 5:24 PM EDTSevere Thunderstorm WarningBUFJefferson51 min
May 11, 5:26 PM EDTSevere Thunderstorm WarningBGMCayuga, Seneca49 min
May 11, 5:33 PM EDTSevere Thunderstorm WarningBUFOswego42 min
May 11, 5:43 PM EDTSevere Thunderstorm WarningBUFLewis62 min
May 11, 5:56 PM EDTTornado WarningBGMCayuga34 min
May 11, 5:58 PM EDTSevere Thunderstorm WarningCTPSullivan47 min
May 11, 6:04 PM EDTSevere Thunderstorm WarningBGMOnondaga26 min
May 11, 6:15 PM EDTSevere Thunderstorm WarningBGMLuzerne, Wyoming60 min
May 11, 6:28 PM EDTSevere Thunderstorm WarningBGMOnondaga32 min
May 11, 6:30 PM EDTTornado WarningBGMLuzerne, Wyoming45 min
May 11, 6:36 PM EDTSevere Thunderstorm WarningBGMCayuga24 min
May 11, 6:59 PM EDTSevere Thunderstorm WarningBGMChemung, Cortland, Tompkins61 min

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Buffalo Intl Airport, NY (KBUF), launched 12:00Z, 5.8 hours before the alert went out and 205 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 2003-05-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 281 joules per kilogram.LCLLFCEL10008507005003002001001 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 2003-05-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 56 square meters per square second.1939587897117Sfc1 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
281 J/kg
Mixed-layer CIN
-165 J/kg
Mixed-layer LCL
850 m above ground
0-6 km bulk shear
51 kt
0-1 km storm-relative helicity
56 m²/s²
0-3 km storm-relative helicity
107 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.5

Open this sounding in Storm Lab

The text

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

000 
WWUS20 KWNS 111745
SEL8  
SPC WW 111750
NYZ000-PAZ000-LOZ000-112300-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 358 
NWS STORM PREDICTION CENTER NORMAN OK 
150 PM EDT SUN MAY 11 2003

THE NWS STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF 

       CENTRAL NEW YORK
       CENTRAL AND EASTERN PENNSYLVANIA
       LAKE ONTARIO

EFFECTIVE THIS SUNDAY AFTERNOON AND EVENING FROM 150 PM UNTIL 700
PM EDT.

...THIS IS A PARTICULARLY DANGEROUS SITUATION...

DESTRUCTIVE TORNADOES...LARGE HAIL TO 2 INCHES IN DIAMETER...
THUNDERSTORM WIND GUSTS TO 80 MPH...AND DANGEROUS LIGHTNING ARE
POSSIBLE IN THESE AREAS.

THE TORNADO WATCH AREA IS ALONG AND 65 STATUTE MILES EAST AND WEST
OF A LINE FROM 50 MILES SOUTHWEST OF HARRISBURG PENNSYLVANIA TO 15
MILES NORTH NORTHEAST OF WATERTOWN NEW YORK.

REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH AREA.
PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR THREATENING
WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS AND POSSIBLE
WARNINGS.


OTHER WATCH INFORMATION...CONTINUE...WW 357...


DISCUSSION...SCATTERED SHOWERS ARE INCREASING OVER CENTRAL PA AND
WESTERN NY AHEAD OF SURFACE COLD FRONT.  RAPID INTENSIFICATION IS
POSSIBLE THIS AFTERNOON...WITH THE DEVELOPMENT OF FAST MOVING
SUPERCELL STORMS AND BOW ECHOES.  VERY FAVORABLE SHEAR PARAMETERS
AND DYNAMIC FORCING SUGGEST AN ENHANCED POTENTIAL FOR TORNADOES AND
VERY DAMAGING WINDS.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 2 INCHES. EXTREME TURBULENCE AND SURFACE WIND
GUSTS TO 70 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500.
MEAN STORM MOTION VECTOR 25040.


...HART

394,0784 441,0771 441,0743 394,0761

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 11, 10:07 AM EDTMesoscale DiscussionSPCAllegany, Broome, Cayuga, Chemung, Chenango, Cortland and 19 more113 min
May 11, 10:30 AM EDTMesoscale DiscussionSPCAllegany, Cattaraugus, Chautauqua, Erie, Genesee, Orleans and 1 more2 hr
May 11, 11:45 AM EDTTornado WatchSPCAllegany, Cattaraugus, Chautauqua, Erie, Genesee, Livingston and 2 more5 hr
May 11, 12:32 PM EDTMesoscale DiscussionSPCBroome, Cayuga, Chemung, Chenango, Cortland, Jefferson and 13 more118 min
May 11, 2:52 PM EDTMesoscale DiscussionSPCAllegany, Cattaraugus, Chautauqua, Erie, Genesee, Livingston and 3 more113 min
May 11, 3:54 PM EDTMesoscale DiscussionSPCBroome, Cayuga, Chemung, Chenango, Cortland, Herkimer and 14 more2 hr

Nearby

Tornado Watches in Pennsylvania, 2003Tornado Watches in New York, 2003Every tornado watch in 2003

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.