Alert archive / New York / Severe Thunderstorm Watches in 2017

Severe Thunderstorm Watch 353

June 18, 20174 states

The Storm Prediction Center issued this severe thunderstorm watch at Jun 18, 2017, 1:37 PM EDT for 4 states. It was in force for 8 hr.

The area

The outline as issued.

The facts

Issued
Jun 18, 2017, 1:37 PM EDT (17:37 UTC)
Expired
Jun 18, 2017, 9:46 PM EDT
In force
8 hr
Issued by
the Storm Prediction Center
Largest hail expected
1.5 in
Strongest gust expected
60 kt
All 73 counties

Allegany County, NY, Broome County, NY, Cattaraugus County, NY, Cayuga County, NY, Chautauqua County, NY, Chemung County, NY, Chenango County, NY, Cortland County, NY, Erie County, NY, Genesee County, NY, Jefferson County, NY, Lewis County, NY, Livingston County, NY, Madison County, NY, Monroe County, NY, Niagara County, NY, Oneida County, NY, Onondaga County, NY, Ontario County, NY, Orleans County, NY, Oswego County, NY, Schuyler County, NY, Seneca County, NY, Steuben County, NY, Tioga County, NY, Tompkins County, NY, Wayne County, NY, Wyoming County, NY, Yates County, NY, Ashtabula County, OH, Belmont County, OH, Carroll County, OH, Columbiana County, OH, Coshocton County, OH, Geauga County, OH, Guernsey County, OH, Harrison County, OH, Holmes County, OH, Jefferson County, OH, Mahoning County, OH, Muskingum County, OH, Portage County, OH, Stark County, OH, Summit County, OH, Trumbull County, OH, Tuscarawas County, OH, Wayne County, OH, Allegheny County, PA, Armstrong County, PA, Beaver County, PA, Bradford County, PA, Butler County, PA, Cameron County, PA, Clarion County, PA, Clearfield County, PA, Crawford County, PA, Elk County, PA, Erie County, PA, Forest County, PA, Indiana County, PA, Jefferson County, PA, Lawrence County, PA, McKean County, PA, Mercer County, PA, Potter County, PA, Tioga County, PA, Venango County, PA, Warren County, PA, Washington County, PA, Westmoreland County, PA, Brooke County, WV, Hancock County, WV, Ohio County, WV

The radar

The Buffalo radar (KBUF), 87 km from the middle of the area, began a volume at 17:42 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
2%
Ten or more severe wind reports
80%
One or more gusts of 65 knots or more
10%
Ten or more severe hail reports
40%
One or more hailstones of 2 inches or more
5%
Six or more combined severe hail and wind reports
90%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Jun 18, 2:23 PM EDTSevere Thunderstorm WarningBUFChautauqua37 min
Jun 18, 2:40 PM EDTSevere Thunderstorm WarningCLECrawford, Erie65 min
Jun 18, 2:41 PM EDTSevere Thunderstorm WarningBUFChautauqua49 min
Jun 18, 2:41 PM EDTSevere Thunderstorm WarningPBZMercer, Venango34 min
Jun 18, 3:10 PM EDTSevere Thunderstorm WarningPBZColumbiana, Jefferson35 min
Jun 18, 3:14 PM EDTSevere Thunderstorm WarningPBZArmstrong, Clarion, Forest, Mercer, Venango46 min
Jun 18, 3:27 PM EDTSevere Thunderstorm WarningPBZBeaver, Butler, Lawrence33 min
Jun 18, 3:30 PM EDTSevere Thunderstorm WarningCTPWarren60 min
Jun 18, 3:45 PM EDTSevere Thunderstorm WarningBUFCattaraugus, Chautauqua60 min
Jun 18, 3:53 PM EDTSevere Thunderstorm WarningBUFCattaraugus, Erie, Wyoming67 min
Jun 18, 3:57 PM EDTSevere Thunderstorm WarningPBZArmstrong, Butler, Clarion, Forest, Jefferson, Venango48 min
Jun 18, 4:14 PM EDTSevere Thunderstorm WarningPBZJefferson46 min
Jun 18, 4:24 PM EDTSevere Thunderstorm WarningCTPMcKean, Warren51 min
Jun 18, 4:29 PM EDTSevere Thunderstorm WarningBUFGenesee, Orleans31 min
Jun 18, 4:40 PM EDTSevere Thunderstorm WarningBUFAllegany, Cattaraugus65 min
Jun 18, 4:49 PM EDTSevere Thunderstorm WarningBUFLivingston, Wyoming56 min
Jun 18, 4:54 PM EDTSevere Thunderstorm WarningBUFGenesee, Livingston, Monroe, Wyoming51 min
Jun 18, 4:57 PM EDTSevere Thunderstorm WarningCTPMcKean, Potter48 min
Jun 18, 5:16 PM EDTSevere Thunderstorm WarningBUFLewis59 min
Jun 18, 5:19 PM EDTSevere Thunderstorm WarningBUFLivingston, Monroe, Ontario, Wayne56 min
Jun 18, 5:28 PM EDTSevere Thunderstorm WarningBUFAllegany, Livingston, Wyoming47 min
Jun 18, 5:46 PM EDTSevere Thunderstorm WarningBUFOswego59 min
Jun 18, 5:47 PM EDTSevere Thunderstorm WarningCTPClinton, Lycoming, Potter, Tioga58 min
Jun 18, 5:51 PM EDTSevere Thunderstorm WarningBGMSteuben, Yates39 min
Jun 18, 6:10 PM EDTSevere Thunderstorm WarningCLEAshtabula, Trumbull50 min
Jun 18, 6:11 PM EDTSevere Thunderstorm WarningBUFOntario, Wayne49 min
Jun 18, 6:25 PM EDTFlash Flood WarningCLEAshtabula4 hr
Jun 18, 6:30 PM EDTSevere Thunderstorm WarningBUFCayuga, Oswego45 min
Jun 18, 6:33 PM EDTSevere Thunderstorm WarningCLEMahoning, Portage, Trumbull57 min
Jun 18, 6:37 PM EDTSevere Thunderstorm WarningCLECrawford, Erie68 min
Jun 18, 6:38 PM EDTSevere Thunderstorm WarningBGMCayuga, Onondaga, Seneca52 min
Jun 18, 6:41 PM EDTSevere Thunderstorm WarningBUFChautauqua64 min
Jun 18, 6:50 PM EDTFlash Flood WarningCLEErie11 hr
Jun 18, 6:55 PM EDTSevere Thunderstorm WarningPBZMercer35 min
Jun 18, 6:57 PM EDTSevere Thunderstorm WarningBGMCayuga, Schuyler, Seneca, Tompkins, Yates48 min
Jun 18, 7:09 PM EDTSevere Thunderstorm WarningCTPWarren66 min
Jun 18, 7:13 PM EDTSevere Thunderstorm WarningBUFJefferson, Lewis, Oswego62 min
Jun 18, 7:16 PM EDTSevere Thunderstorm WarningBGMChemung, Schuyler, Steuben, Tompkins44 min
Jun 18, 7:29 PM EDTSevere Thunderstorm WarningCLEMahoning, Trumbull46 min
Jun 18, 7:35 PM EDTSevere Thunderstorm WarningBGMChemung, Tioga, Tompkins40 min
Jun 18, 7:36 PM EDTSevere Thunderstorm WarningBUFCattaraugus, Chautauqua54 min
Jun 18, 7:55 PM EDTSevere Thunderstorm WarningBGMCayuga, Chemung, Cortland, Onondaga, Tioga, Tompkins50 min
Jun 18, 8:08 PM EDTSevere Thunderstorm WarningBGMBroome, Tioga, Tompkins52 min
Jun 18, 8:13 PM EDTSevere Thunderstorm WarningBUFCattaraugus, Chautauqua, Erie, Wyoming29 min
Jun 18, 8:13 PM EDTSevere Thunderstorm WarningBUFLewis32 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, 5.6 hours before the alert went out and 86 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 2017-06-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 199 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 2017-06-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 163 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
199 J/kg
Mixed-layer CIN
-56 J/kg
Mixed-layer LCL
1297 m above ground
0-6 km bulk shear
25 kt
0-1 km storm-relative helicity
163 m²/s²
0-3 km storm-relative helicity
196 m²/s²
Significant tornado parameter
0.1
Supercell composite
2.5

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 18, 12:31 PM EDTMesoscale DiscussionSPCAllegany, Cattaraugus, Cayuga, Chautauqua, Chemung, Cortland and 18 more119 min
Jun 18, 3:31 PM EDTMesoscale DiscussionSPCBroome, Chenango, Clinton, Delaware, Essex, Franklin and 10 more2 hr
Jun 18, 4:30 PM EDTMesoscale DiscussionSPCAllegany, Cattaraugus, Cayuga, Chautauqua, Erie, Genesee and 10 more90 min

Nearby

Severe Thunderstorm Watches in New York, 2017Severe Thunderstorm Watches in Pennsylvania, 2017Severe Thunderstorm Watches in Ohio, 2017Every severe thunderstorm watch in 2017

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.