Alert archive / Virginia / Mesoscale Discussions in 2015

Mesoscale Discussion 1850

October 9, 2015Sussex County, Delaware; 5 counties in Maryland; 15 counties in Virginia

The Storm Prediction Center issued this mesoscale discussion at Oct 9, 2015, 7:40 PM EDT for Sussex County, Delaware; 5 counties in Maryland; 15 counties in Virginia. It was in force for 95 min.

The area

The outline as issued.

The facts

Issued: Oct 9, 2015, 7:40 PM EDT (23:40 UTC)
Expired: Oct 9, 2015, 9:15 PM EDT
In force: 95 min
Issued by: the Storm Prediction Center

All 21 counties

Sussex County, DE, Dorchester County, MD, Saint Mary's County, MD, Somerset County, MD, Wicomico County, MD, Worcester County, MD, Accomack County, VA, Caroline County, VA, Essex County, VA, Gloucester County, VA, Hanover County, VA, King and Queen County, VA, King William County, VA, Lancaster County, VA, Mathews County, VA, Middlesex County, VA, New Kent County, VA, Northampton County, VA, Northumberland County, VA, Richmond County, VA, Westmoreland County, VA

The radar

The Dover AFB radar (KDOX), 104 km from the middle of the area, began a volume at 23:43 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, 11.7 hours before the alert went out and 162 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: 43 J/kg
Mixed-layer CIN: -181 J/kg
Mixed-layer LCL: 1203 m above ground
0-6 km bulk shear: 37 kt
0-1 km storm-relative helicity: 114 m²/s²
0-3 km storm-relative helicity: 126 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

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SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Oct 9, 3:11 PM EDT	Mesoscale Discussion	SPC	New Castle	2 hr
Oct 9, 3:34 PM EDT	Severe Thunderstorm Watch	SPC	New Castle	4 hr
Oct 9, 4:54 PM EDT	Mesoscale Discussion	SPC	New Castle	96 min
Oct 9, 2:48 PM EDT	Mesoscale Discussion	SPC	Allegany, Garrett	57 min

Nearby

Mesoscale Discussions in Virginia, 2015 Mesoscale Discussions in Maryland, 2015 Mesoscale Discussions in Delaware, 2015 Every mesoscale discussion 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.