Alert archive / Pennsylvania / Severe Thunderstorm Watches in 2009

Severe Thunderstorm Watch 355

June 9, 200910 counties in New York; 37 counties in Pennsylvania

The Storm Prediction Center issued this severe thunderstorm watch at Jun 9, 2009, 1:31 PM EDT for 10 counties in New York; 37 counties in Pennsylvania. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued
Jun 9, 2009, 1:31 PM EDT (17:31 UTC)
Expired
Jun 9, 2009, 8:00 PM EDT
In force
6 hr
Issued by
the Storm Prediction Center
Largest hail expected
1.5 in
Strongest gust expected
60 kt
All 47 counties

Broome County, NY, Chenango County, NY, Delaware County, NY, Fulton County, NY, Herkimer County, NY, Montgomery County, NY, Otsego County, NY, Schoharie County, NY, Sullivan County, NY, Tioga County, NY, Adams County, PA, Bedford County, PA, Berks County, PA, Blair County, PA, Bradford County, PA, Carbon 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, Lackawanna County, PA, Lancaster County, PA, Lebanon County, PA, Lehigh County, PA, Luzerne County, PA, Lycoming County, PA, Mifflin County, PA, Monroe County, PA, Montour County, PA, Northampton County, PA, Northumberland County, PA, Perry County, PA, Pike County, PA, Schuylkill County, PA, Snyder County, PA, Sullivan County, PA, Susquehanna County, PA, Tioga County, PA, Union County, PA, Wayne County, PA, Wyoming County, PA, York County, PA

The radar

The Binghamton radar (KBGM), 62 km from the middle of the area, began a volume at 17:31 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 SPC expected

The probabilities SPC published with the watch, for the watch area over its life.

Two or more tornadoes
20%
One or more EF2 to EF5 tornadoes
5%
Ten or more severe wind reports
30%
One or more gusts of 65 knots or more
20%
Ten or more severe hail reports
30%
One or more hailstones of 2 inches or more
20%
Six or more combined severe hail and wind reports
60%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Jun 9, 1:42 PM EDTSevere Thunderstorm WarningCTPAdams, Cumberland, York63 min
Jun 9, 1:49 PM EDTSevere Thunderstorm WarningCTPBedford, Somerset56 min
Jun 9, 1:54 PM EDTSevere Thunderstorm WarningCTPCumberland, Dauphin, Lancaster, Lebanon, York66 min
Jun 9, 1:56 PM EDTSevere Thunderstorm WarningBGMOneida, Otsego64 min
Jun 9, 2:00 PM EDTSevere Thunderstorm WarningCTPFranklin, Fulton60 min
Jun 9, 2:02 PM EDTSevere Thunderstorm WarningALYHerkimer58 min
Jun 9, 2:07 PM EDTSevere Thunderstorm WarningCTPLancaster23 min
Jun 9, 2:16 PM EDTSevere Thunderstorm WarningCTPBedford, Fulton44 min
Jun 9, 2:20 PM EDTFlash Flood WarningPHIBerks, Chester3 hr
Jun 9, 2:24 PM EDTSevere Thunderstorm WarningPHIBerks, Chester, Montgomery66 min
Jun 9, 2:35 PM EDTSevere Thunderstorm WarningCTPLancaster25 min
Jun 9, 2:41 PM EDTSevere Thunderstorm WarningCTPAdams, Cumberland, Franklin, Perry, York64 min
Jun 9, 2:50 PM EDTTornado WarningCTPLancaster25 min
Jun 9, 2:55 PM EDTSevere Thunderstorm WarningBGMSullivan55 min
Jun 9, 2:57 PM EDTSevere Thunderstorm WarningCTPLancaster, York63 min
Jun 9, 2:59 PM EDTSevere Thunderstorm WarningBGMOtsego61 min
Jun 9, 3:12 PM EDTSevere Thunderstorm WarningCTPFranklin33 min
Jun 9, 3:17 PM EDTTornado WarningBGMSullivan28 min
Jun 9, 3:23 PM EDTSevere Thunderstorm WarningCTPLancaster37 min
Jun 9, 3:25 PM EDTSevere Thunderstorm WarningBGMOtsego50 min
Jun 9, 3:31 PM EDTSevere Thunderstorm WarningBGMDelaware, Otsego44 min
Jun 9, 3:34 PM EDTSevere Thunderstorm WarningCTPDauphin, Juniata, Northumberland, Perry41 min
Jun 9, 3:44 PM EDTTornado WarningBGMSullivan31 min
Jun 9, 3:44 PM EDTSevere Thunderstorm WarningCTPAdams, Franklin, York49 min
Jun 9, 4:11 PM EDTTornado WarningBGMDelaware34 min
Jun 9, 4:11 PM EDTSevere Thunderstorm WarningCTPLancaster, York49 min
Jun 9, 4:12 PM EDTSevere Thunderstorm WarningBGMSullivan33 min
Jun 9, 4:13 PM EDTSevere Thunderstorm WarningBGMOtsego47 min
Jun 9, 4:18 PM EDTSevere Thunderstorm WarningBGMBroome42 min
Jun 9, 4:43 PM EDTTornado WarningBGMDelaware47 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

Albany, NY (KALY), launched 12:00Z, 5.5 hours before the alert went out and 226 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, Albany, NY at 12:00Z on 2009-06-09Temperature 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, Albany, NY at 12:00Z on 2009-06-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 101 square meters per square second.193958Sfc1 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
523 m above ground
0-6 km bulk shear
50 kt
0-1 km storm-relative helicity
101 m²/s²
0-3 km storm-relative helicity
190 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 9, 6:01 AM EDTMesoscale DiscussionSPCBronx, Kings, New York, Orange, Putnam, Queens and 5 more59 min
Jun 9, 11:48 AM EDTMesoscale DiscussionSPCAllegany, Broome, Cayuga, Chemung, Chenango, Cortland and 9 more87 min
Jun 9, 3:40 PM EDTMesoscale DiscussionSPCBroome, Chenango, Cortland, Delaware, Madison, Montgomery and 6 more65 min

Nearby

Severe Thunderstorm Watches in Pennsylvania, 2009Severe Thunderstorm Watches in New York, 2009Every severe thunderstorm watch in 2009

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.