Alert archive / Virginia / Severe Thunderstorm Watches in 2016

Severe Thunderstorm Watch 314

July 1, 20165 states

The Storm Prediction Center issued this severe thunderstorm watch at Jul 1, 2016, 1:56 PM EDT for 5 states. It was in force for 7 hr.

The area

The outline as issued.

The facts

Issued: Jul 1, 2016, 1:56 PM EDT (17:56 UTC)
Expired: Jul 1, 2016, 8:44 PM EDT
In force: 7 hr
Issued by: the Storm Prediction Center
Largest hail expected: 1.5 in
Strongest gust expected: 60 kt

All 71 counties

Kent County, DE, New Castle County, DE, Sussex County, DE, Anne Arundel County, MD, Baltimore County, MD, Calvert County, MD, Caroline County, MD, Carroll County, MD, Cecil County, MD, Charles 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, Saint Mary's County, MD, Talbot County, MD, Atlantic County, NJ, Burlington County, NJ, Camden County, NJ, Cape May County, NJ, Cumberland County, NJ, Gloucester County, NJ, Hunterdon County, NJ, Mercer County, NJ, Middlesex County, NJ, Monmouth County, NJ, Morris County, NJ, Ocean County, NJ, Salem County, NJ, Somerset County, NJ, Sussex County, NJ, Warren County, NJ, Adams County, PA, Berks County, PA, Bucks County, PA, Carbon County, PA, Chester County, PA, Dauphin County, PA, Delaware County, PA, Lancaster County, PA, Lebanon County, PA, Lehigh County, PA, Monroe County, PA, Montgomery County, PA, Northampton County, PA, Philadelphia County, PA, Schuylkill County, PA, York County, PA, Arlington County, VA, City of Alexandria, VA, City of Fairfax, VA, City of Falls Church, VA, City of Fredericksburg, VA, City of Manassas, VA, City of Manassas Park, VA, Culpeper County, VA, Fairfax County, VA, Fauquier County, VA, Greene County, VA, King George County, VA, Loudoun County, VA, Madison County, VA, Orange County, VA, Prince William County, VA, Rappahannock County, VA, Spotsylvania County, VA, Stafford County, VA

The radar

The Dover AFB radar (KDOX), 109 km from the middle of the area, began a volume at 17:59 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: 40%
One or more gusts of 65 knots or more: 5%
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: 70%

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
Jul 1, 2:10 PM EDT	Severe Thunderstorm Warning	CTP	Lancaster, York	50 min
Jul 1, 2:19 PM EDT	Severe Thunderstorm Warning	PHI	Mercer, Middlesex, Monmouth	41 min
Jul 1, 2:49 PM EDT	Severe Thunderstorm Warning	CTP	Lancaster, Lebanon	41 min
Jul 1, 2:52 PM EDT	Severe Thunderstorm Warning	CTP	Lancaster	38 min
Jul 1, 2:57 PM EDT	Severe Thunderstorm Warning	PHI	Monmouth	48 min
Jul 1, 3:05 PM EDT	Severe Thunderstorm Warning	PHI	Cumberland	40 min
Jul 1, 3:55 PM EDT	Severe Thunderstorm Warning	PHI	Burlington	35 min
Jul 1, 4:30 PM EDT	Severe Thunderstorm Warning	PHI	New Castle	45 min
Jul 1, 4:36 PM EDT	Flash Flood Warning	PHI	Monmouth	4 hr
Jul 1, 4:52 PM EDT	Severe Thunderstorm Warning	LWX	Culpeper, Fauquier, Madison, Orange, Rappahannock, Spotsylvania	53 min
Jul 1, 4:58 PM EDT	Severe Thunderstorm Warning	PHI	Cumberland	47 min
Jul 1, 5:14 PM EDT	Flash Flood Warning	PHI	Cumberland	4 hr
Jul 1, 5:37 PM EDT	Severe Thunderstorm Warning	PHI	Atlantic	38 min
Jul 1, 5:41 PM EDT	Severe Thunderstorm Warning	LWX	Anne Arundel	38 min
Jul 1, 5:47 PM EDT	Severe Thunderstorm Warning	PHI	Kent, Queen Anne's	43 min
Jul 1, 6:20 PM EDT	Flash Flood Warning	PHI	Atlantic, Burlington, Cumberland, Ocean	4 hr
Jul 1, 6:21 PM EDT	Severe Thunderstorm Warning	LWX	Anne Arundel, Prince George's	22 min
Jul 1, 6:28 PM EDT	Severe Thunderstorm Warning	LWX	Spotsylvania	27 min
Jul 1, 6:29 PM EDT	Flash Flood Warning	PHI	Caroline, Kent, Queen Anne's, Talbot	4 hr
Jul 1, 7:40 PM EDT	Flash Flood Warning	PHI	Caroline, Talbot	4 hr

Discussions around it

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

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 5.9 hours before the alert went out and 155 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: 20 J/kg
Mixed-layer CIN: -114 J/kg
Mixed-layer LCL: 1086 m above ground
0-6 km bulk shear: 44 kt
0-1 km storm-relative helicity: 81 m²/s²
0-3 km storm-relative helicity: 124 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
Jul 1, 12:51 PM EDT	Mesoscale Discussion	SPC	New Castle	114 min
Jul 1, 5:43 PM EDT	Mesoscale Discussion	SPC	New Castle	92 min
Jul 1, 1:32 PM EDT	Tornado Watch	SPC	Bergen, Essex, Hudson, Passaic, Union	8 hr
Jul 1, 5:21 PM EDT	Mesoscale Discussion	SPC	Bergen, Essex, Hudson, Morris, Passaic, Sussex and 2 more	84 min

Nearby

Severe Thunderstorm Watches in Virginia, 2016 Severe Thunderstorm Watches in Maryland, 2016 Severe Thunderstorm Watches in New Jersey, 2016 Every severe thunderstorm watch in 2016

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.