Alert archive / New York / Severe Thunderstorm Watches in 2015

Severe Thunderstorm Watch 227

May 27, 20158 states

The Storm Prediction Center issued this severe thunderstorm watch at May 27, 2015, 12:54 PM EDT for 8 states. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued: May 27, 2015, 12:54 PM EDT (16:54 UTC)
Expired: May 27, 2015, 7:00 PM EDT
In force: 6 hr
Issued by: the Storm Prediction Center
Largest hail expected: 1.5 in
Strongest gust expected: 60 kt

All 117 counties

Kent County, DE, New Castle County, DE, Sussex County, DE, Berkshire County, MA, Anne Arundel County, MD, Baltimore County, MD, Calvert County, MD, Caroline County, MD, Carroll County, MD, Cecil County, MD, City of Baltimore, MD, Frederick County, MD, Harford County, MD, Howard County, MD, Kent County, MD, Montgomery County, MD, Prince George's County, MD, Queen Anne's County, MD, Talbot County, MD, Atlantic County, NJ, Bergen County, NJ, Burlington County, NJ, Camden County, NJ, Cape May County, NJ, Cumberland County, NJ, Essex County, NJ, Gloucester County, NJ, Hudson County, NJ, Hunterdon County, NJ, Mercer County, NJ, Middlesex County, NJ, Monmouth County, NJ, Morris County, NJ, Ocean County, NJ, Passaic County, NJ, Salem County, NJ, Somerset County, NJ, Sussex County, NJ, Union County, NJ, Warren County, NJ, Albany County, NY, Broome County, NY, Chenango County, NY, Clinton County, NY, Columbia County, NY, Delaware County, NY, Dutchess County, NY, Essex County, NY, Franklin County, NY, Fulton County, NY, Greene County, NY, Hamilton County, NY, Herkimer County, NY, Madison County, NY, Montgomery County, NY, Oneida County, NY, Orange County, NY, Otsego County, NY, Putnam County, NY, Rensselaer County, NY, Rockland County, NY, Saratoga County, NY, Schenectady County, NY, Schoharie County, NY, Sullivan County, NY, Ulster County, NY, Warren County, NY, Washington County, NY, Westchester County, NY, Adams County, PA, Berks County, PA, Bucks County, PA, Carbon County, PA, Chester County, PA, Columbia County, PA, Cumberland County, PA, Dauphin County, PA, Delaware County, PA, Lackawanna County, PA, Lancaster County, PA, Lebanon County, PA, Lehigh County, PA, Luzerne County, PA, Monroe County, PA, Montgomery County, PA, Montour County, PA, Northampton County, PA, Northumberland County, PA, Perry County, PA, Philadelphia County, PA, Pike County, PA, Schuylkill County, PA, Sullivan County, PA, Susquehanna County, PA, Wayne County, PA, Wyoming County, PA, York County, PA, Arlington County, VA, City of Alexandria, VA, City of Fairfax, VA, City of Falls Church, VA, Fairfax County, VA, Loudoun County, VA, Addison County, VT, Bennington County, VT, Caledonia County, VT, Chittenden County, VT, Essex County, VT, Franklin County, VT, Grand Isle County, VT, Lamoille County, VT, Orange County, VT, Orleans County, VT, Rutland County, VT, Washington County, VT, Windham County, VT, Windsor County, VT

The radar

The Albany radar (KENX), 32 km from the middle of the area, began a volume at 16:56 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: 10%
One or more EF2 to EF5 tornadoes: 2%
Ten or more severe wind reports: 40%
One or more gusts of 65 knots or more: 10%
Ten or more severe hail reports: 30%
One or more hailstones of 2 inches or more: 10%
Six or more combined severe hail and wind reports: 90%

Warnings issued inside it

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

Issued	Product	Office	Counties	Lasted
May 27, 1:21 PM EDT	Severe Thunderstorm Warning	BTV	Clinton, Essex	54 min
May 27, 1:22 PM EDT	Severe Thunderstorm Warning	BTV	Franklin, Grand Isle, Orleans	53 min
May 27, 1:42 PM EDT	Severe Thunderstorm Warning	CTP	Dauphin, Lebanon, York	48 min
May 27, 1:50 PM EDT	Severe Thunderstorm Warning	CTP	Adams, York	55 min
May 27, 1:53 PM EDT	Severe Thunderstorm Warning	BTV	Essex	56 min
May 27, 2:33 PM EDT	Severe Thunderstorm Warning	CTP	Lancaster, York	42 min
May 27, 2:56 PM EDT	Severe Thunderstorm Warning	CTP	Lancaster, Lebanon	34 min
May 27, 3:26 PM EDT	Severe Thunderstorm Warning	BGM	Sullivan	64 min
May 27, 3:29 PM EDT	Severe Thunderstorm Warning	BGM	Delaware, Sullivan	61 min
May 27, 4:36 PM EDT	Severe Thunderstorm Warning	PHI	Chester	39 min
May 27, 4:40 PM EDT	Severe Thunderstorm Warning	BTV	Caledonia, Essex, Orange, Windsor	35 min
May 27, 5:00 PM EDT	Severe Thunderstorm Warning	OKX	Orange	30 min
May 27, 5:02 PM EDT	Severe Thunderstorm Warning	ALY	Berkshire	58 min
May 27, 5:07 PM EDT	Severe Thunderstorm Warning	PHI	Bucks, Chester, Delaware, Montgomery	53 min
May 27, 5:21 PM EDT	Severe Thunderstorm Warning	ALY	Berkshire	54 min
May 27, 5:25 PM EDT	Severe Thunderstorm Warning	PHI	New Castle	44 min
May 27, 5:29 PM EDT	Severe Thunderstorm Warning	OKX	Orange	31 min
May 27, 5:40 PM EDT	Severe Thunderstorm Warning	ALY	Dutchess, Ulster	65 min
May 27, 5:59 PM EDT	Severe Thunderstorm Warning	ALY	Berkshire	16 min
May 27, 6:37 PM EDT	Severe Thunderstorm Warning	OKX	Bergen	38 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, 4.9 hours before the alert went out and 52 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 101 J/kg
Mixed-layer CIN: -166 J/kg
Mixed-layer LCL: 994 m above ground
0-6 km bulk shear: 32 kt
0-1 km storm-relative helicity: 188 m²/s²
0-3 km storm-relative helicity: 193 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 27, 12:21 PM EDT	Mesoscale Discussion	SPC	Kent, New Castle	54 min
May 27, 2:59 PM EDT	Mesoscale Discussion	SPC	Kent, New Castle, Sussex	2 hr
May 27, 11:50 AM EDT	Mesoscale Discussion	SPC	Berkshire	85 min
May 27, 4:49 PM EDT	Mesoscale Discussion	SPC	Berkshire, Franklin, Hampden, Hampshire	86 min
May 27, 5:02 PM EDT	Severe Thunderstorm Watch	SPC	Franklin, Hampden, Hampshire, Suffolk, Worcester	4 hr
May 27, 7:21 PM EDT	Mesoscale Discussion	SPC	Hampden, Hampshire, Worcester	54 min

Nearby

Severe Thunderstorm Watches in New York, 2015 Severe Thunderstorm Watches in Pennsylvania, 2015 Severe Thunderstorm Watches in New Jersey, 2015 Every severe thunderstorm watch in 2015

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.