Alert archive / New York / Severe Thunderstorm Watches in 2014

Severe Thunderstorm Watch 497

September 6, 20147 states

The Storm Prediction Center issued this severe thunderstorm watch at Sep 6, 2014, 1:22 PM EDT for 7 states. It was in force for 8 hr.

The area

The outline as issued.

The facts

Issued
Sep 6, 2014, 1:22 PM EDT (17:22 UTC)
Expired
Sep 6, 2014, 9:00 PM EDT
In force
8 hr
Issued by
the Storm Prediction Center
Largest hail expected
1 in
Strongest gust expected
60 kt
All 71 counties

Capitol Planning Region, CT, Greater Bridgeport Planning Region, CT, Lower Connecticut River Valley Planning Region, CT, Naugatuck Valley Planning Region, CT, Northeastern Connecticut Planning Region, CT, Northwest Hills Planning Region, CT, Southeastern Connecticut Planning Region, CT, Berkshire County, MA, Bristol County, MA, Essex County, MA, Franklin County, MA, Hampden County, MA, Hampshire County, MA, Middlesex County, MA, Norfolk County, MA, Plymouth County, MA, Suffolk County, MA, Worcester County, MA, Androscoggin County, ME, Cumberland County, ME, Franklin County, ME, Hancock County, ME, Kennebec County, ME, Knox County, ME, Lincoln County, ME, Oxford County, ME, Penobscot County, ME, Piscataquis County, ME, Sagadahoc County, ME, Somerset County, ME, Waldo County, ME, Washington County, ME, York County, ME, Belknap County, NH, Carroll County, NH, Cheshire County, NH, Coos County, NH, Grafton County, NH, Hillsborough County, NH, Merrimack County, NH, Rockingham County, NH, Strafford County, NH, Sullivan County, NH, Albany County, NY, Bronx County, NY, Columbia County, NY, Dutchess County, NY, Greene County, NY, Kings County, NY, Nassau County, NY, New York County, NY, Orange County, NY, Putnam County, NY, Queens County, NY, Rensselaer County, NY, Richmond County, NY, Rockland County, NY, Saratoga County, NY, Schenectady County, NY, Schoharie County, NY, Suffolk County, NY, Ulster County, NY, Washington County, NY, Westchester County, NY, Bristol County, RI, Kent County, RI, Newport County, RI, Providence County, RI, Washington County, RI, Bennington County, VT, Windham County, VT

The radar

The Portland,ME radar (KGYX), 37 km from the middle of the area, began a volume at 17:24 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
20%
One or more hailstones of 2 inches or more
5%
Six or more combined severe hail and wind reports
95%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Sep 6, 2:38 PM EDTSevere Thunderstorm WarningALYNorthwest Hills Planning Region67 min
Sep 6, 3:08 PM EDTSevere Thunderstorm WarningBOXMiddlesex, Worcester31 min
Sep 6, 3:18 PM EDTSevere Thunderstorm WarningGYXYork27 min
Sep 6, 3:36 PM EDTSevere Thunderstorm WarningOKXGreater Bridgeport Planning Region39 min
Sep 6, 3:59 PM EDTSevere Thunderstorm WarningGYXCarroll, Grafton46 min
Sep 6, 4:00 PM EDTSevere Thunderstorm WarningBOXFranklin, Worcester60 min
Sep 6, 4:17 PM EDTSevere Thunderstorm WarningOKXGreater Bridgeport Planning Region43 min
Sep 6, 4:18 PM EDTSevere Thunderstorm WarningBOXEssex, Middlesex57 min
Sep 6, 4:22 PM EDTTornado WarningBOXFranklin, Worcester24 min
Sep 6, 4:29 PM EDTTornado WarningBOXEssex, Middlesex31 min
Sep 6, 4:49 PM EDTSevere Thunderstorm WarningOKXGreater Bridgeport Planning Region41 min
Sep 6, 4:59 PM EDTSevere Thunderstorm WarningBOXEssex, Middlesex61 min
Sep 6, 5:03 PM EDTSevere Thunderstorm WarningBOXMiddlesex, Worcester42 min
Sep 6, 5:27 PM EDTSevere Thunderstorm WarningGYXAndroscoggin, Cumberland, Kennebec, Oxford33 min
Sep 6, 5:43 PM EDTSevere Thunderstorm WarningBOXFranklin, Hampshire, Worcester26 min
Sep 6, 5:50 PM EDTSevere Thunderstorm WarningBOXEssex, Middlesex40 min
Sep 6, 5:58 PM EDTSevere Thunderstorm WarningGYXAndroscoggin, Cumberland, Sagadahoc32 min
Sep 6, 6:30 PM EDTSevere Thunderstorm WarningGYXCumberland, Lincoln, Sagadahoc30 min
Sep 6, 7:42 PM EDTSevere Thunderstorm WarningALYDutchess33 min
Sep 6, 7:47 PM EDTSevere Thunderstorm WarningOKXPutnam43 min
Sep 6, 8:42 PM EDTSevere Thunderstorm WarningBOXPlymouth31 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

Gray, ME (KGYX), launched 12:00Z, 5.4 hours before the alert went out and 37 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, Gray, ME at 12:00Z on 2014-09-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 494 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, Gray, ME at 12:00Z on 2014-09-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 127 square meters per square second.1939Sfc1 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
494 J/kg
Mixed-layer CIN
-168 J/kg
Mixed-layer LCL
989 m above ground
0-6 km bulk shear
30 kt
0-1 km storm-relative helicity
127 m²/s²
0-3 km storm-relative helicity
121 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.6

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Sep 6, 12:31 PM EDTMesoscale DiscussionSPC89 min
Sep 6, 4:20 PM EDTMesoscale DiscussionSPC85 min
Sep 6, 7:31 PM EDTMesoscale DiscussionSPC89 min

Nearby

Severe Thunderstorm Watches in New York, 2014Severe Thunderstorm Watches in Maine, 2014Severe Thunderstorm Watches in Massachusetts, 2014Every severe thunderstorm watch in 2014

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.