Alert archive / Virginia / Mesoscale Discussions in 2016

Mesoscale Discussion 1107

July 1, 20165 states

The Storm Prediction Center issued this mesoscale discussion at Jul 1, 2016, 5:43 PM EDT for 5 states. It was in force for 92 min.

The area

The outline as issued.

The facts

Issued: Jul 1, 2016, 5:43 PM EDT (21:43 UTC)
Expired: Jul 1, 2016, 7:15 PM EDT
In force: 92 min
Issued by: the Storm Prediction Center

All 36 counties

New Castle County, DE, Anne Arundel County, MD, Baltimore County, MD, Calvert County, MD, Caroline County, MD, Cecil County, MD, Charles County, MD, City of Baltimore, 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, Salem County, NJ, Chester County, PA, Delaware 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, 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 Sterling radar (KLWX), 47 km from the middle of the area, began a volume at 21:43 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.

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 9.7 hours before the alert went out and 40 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

The text

As transmitted.

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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, 1:56 PM EDT	Severe Thunderstorm Watch	SPC	Kent, New Castle, Sussex	7 hr
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

Mesoscale Discussions in Virginia, 2016 Mesoscale Discussions in Maryland, 2016 Mesoscale Discussions in Pennsylvania, 2016 Every mesoscale discussion 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.