Alert archive / Virginia / Mesoscale Discussions in 2009

Mesoscale Discussion 941

June 3, 20095 states

The Storm Prediction Center issued this mesoscale discussion at Jun 3, 2009, 7:10 PM EDT for 5 states. It was in force for 95 min.

The area

The outline as issued.

The facts

Issued
Jun 3, 2009, 7:10 PM EDT (23:10 UTC)
Expired
Jun 3, 2009, 8:45 PM EDT
In force
95 min
Issued by
the Storm Prediction Center
All 127 counties

Kent County, DE, New Castle County, DE, Sussex County, DE, Allegany County, MD, 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, Dorchester County, 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, Somerset County, MD, Talbot County, MD, Washington County, MD, Wicomico County, MD, Worcester County, MD, Atlantic County, NJ, Cape May County, NJ, Cumberland County, NJ, Gloucester County, NJ, Salem County, NJ, Accomack County, VA, Albemarle County, VA, Amelia County, VA, Amherst County, VA, Appomattox County, VA, Arlington County, VA, Augusta County, VA, Bedford County, VA, Bland County, VA, Botetourt County, VA, Buchanan County, VA, Buckingham County, VA, Campbell County, VA, Caroline County, VA, Carroll County, VA, Chesterfield County, VA, City of Alexandria, VA, City of Buena Vista, VA, City of Charlottesville, VA, City of Fairfax, VA, City of Falls Church, VA, City of Fredericksburg, VA, City of Galax, VA, City of Harrisonburg, VA, City of Lexington, VA, City of Lynchburg, VA, City of Manassas, VA, City of Manassas Park, VA, City of Radford, VA, City of Richmond, VA, City of Roanoke, VA, City of Salem, VA, City of Staunton, VA, City of Waynesboro, VA, City of Winchester, VA, Clarke County, VA, Craig County, VA, Culpeper County, VA, Cumberland County, VA, Dickenson County, VA, Essex County, VA, Fairfax County, VA, Fauquier County, VA, Floyd County, VA, Fluvanna County, VA, Franklin County, VA, Frederick County, VA, Giles County, VA, Goochland County, VA, Grayson County, VA, Greene County, VA, Hanover County, VA, Henrico County, VA, Highland County, VA, King and Queen County, VA, King George County, VA, King William County, VA, Lancaster County, VA, Loudoun County, VA, Louisa County, VA, Madison County, VA, Middlesex County, VA, Montgomery County, VA, Nelson County, VA, New Kent County, VA, Northumberland County, VA, Orange County, VA, Page County, VA, Patrick County, VA, Powhatan County, VA, Prince William County, VA, Pulaski County, VA, Rappahannock County, VA, Richmond County, VA, Roanoke County, VA, Rockbridge County, VA, Rockingham County, VA, Shenandoah County, VA, Smyth County, VA, Spotsylvania County, VA, Stafford County, VA, Tazewell County, VA, Warren County, VA, Westmoreland County, VA, Wythe County, VA, Berkeley County, WV, Grant County, WV, Hampshire County, WV, Hardy County, WV, Jefferson County, WV, McDowell County, WV, Mineral County, WV, Mingo County, WV, Morgan County, WV, Pendleton County, WV, Wyoming County, WV

The radar

The Roanoke radar (KFCX), 122 km from the middle of the area, began a volume at 23:13 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

Roanoke, VA (KRNK), launched 12:00Z, 11.2 hours before the alert went out and 67 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, Roanoke, VA at 12:00Z on 2009-06-03Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 451 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, Roanoke, VA at 12:00Z on 2009-06-03The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 41 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
451 J/kg
Mixed-layer CIN
-97 J/kg
Mixed-layer LCL
1134 m above ground
0-6 km bulk shear
23 kt
0-1 km storm-relative helicity
41 m²/s²
0-3 km storm-relative helicity
34 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.

IssuedProductOfficeCountiesLasted
Jun 3, 1:06 PM EDTSevere Thunderstorm WatchSPCKent, New Castle, Sussex9 hr
Jun 3, 4:34 PM EDTMesoscale DiscussionSPCKent, New Castle, Sussex86 min
Jun 3, 12:41 PM EDTMesoscale DiscussionSPCAnne Arundel, Calvert, Charles, Howard, Montgomery, Prince George's and 2 more64 min
Jun 2, 9:19 PM EDTMesoscale DiscussionSPCCabell, Calhoun, Doddridge, Gilmer, Harrison, Jackson and 10 more56 min
Jun 3, 12:12 PM EDTMesoscale DiscussionSPCBarbour, Boone, Braxton, Cabell, Calhoun, Clay and 24 more93 min

Nearby

Mesoscale Discussions in Virginia, 2009Mesoscale Discussions in Maryland, 2009Mesoscale Discussions in West Virginia, 2009Every mesoscale discussion in 2009

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.