Alert archive / Virginia / Mesoscale Discussions in 2017

Mesoscale Discussion 242

March 1, 20175 states

The Storm Prediction Center issued this mesoscale discussion at Mar 1, 2017, 12:25 PM EST for 5 states. It was in force for 65 min.

The area

The outline as issued.

The facts

Issued: Mar 1, 2017, 12:25 PM EST (17:25 UTC)
Expired: Mar 1, 2017, 1:30 PM EST
In force: 65 min
Issued by: the Storm Prediction Center

All 70 counties

Baltimore County, MD, Carroll County, MD, City of Baltimore, MD, Frederick County, MD, Howard County, MD, Montgomery County, MD, Washington County, MD, Alleghany County, NC, Rockingham County, NC, Stokes County, NC, Surry County, NC, Adams County, PA, Cumberland County, PA, Franklin County, PA, Fulton County, PA, York County, PA, Albemarle County, VA, Amherst County, VA, Arlington County, VA, Augusta County, VA, Bedford County, VA, Botetourt County, VA, Campbell County, VA, Carroll County, VA, City of Alexandria, VA, City of Buena Vista, VA, City of Charlottesville, VA, City of Danville, 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 Martinsville, VA, City of Roanoke, VA, City of Salem, VA, City of Staunton, VA, City of Waynesboro, VA, City of Winchester, VA, Clarke County, VA, Culpeper County, VA, Fairfax County, VA, Fauquier County, VA, Floyd County, VA, Franklin County, VA, Frederick County, VA, Greene County, VA, Henry County, VA, Loudoun County, VA, Madison County, VA, Nelson County, VA, Orange County, VA, Page County, VA, Patrick County, VA, Pittsylvania County, VA, Prince William County, VA, Rappahannock County, VA, Rockbridge County, VA, Rockingham County, VA, Shenandoah County, VA, Stafford County, VA, Warren County, VA, Berkeley County, WV, Hampshire County, WV, Jefferson County, WV, Morgan County, WV

The radar

The Sterling radar (KLWX), 102 km from the middle of the area, began a volume at 17:25 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 watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 5.4 hours before the alert went out and 107 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: 32 J/kg
Mixed-layer CIN: -201 J/kg
Mixed-layer LCL: 1104 m above ground
0-6 km bulk shear: 69 kt
0-1 km storm-relative helicity: 118 m²/s²
0-3 km storm-relative helicity: 142 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
Mar 1, 9:44 AM EST	Mesoscale Discussion	SPC	Allegany, Baltimore, Carroll, Charles, Frederick, Garrett and 6 more	91 min
Mar 1, 10:38 AM EST	Severe Thunderstorm Watch	SPC	Allegany, Anne Arundel, Baltimore, Calvert, Carroll, Charles and 8 more	4 hr
Mar 1, 12:50 PM EST	Mesoscale Discussion	SPC	Caroline, Dorchester, Saint Mary's, Somerset, Wicomico, Worcester	55 min
Mar 1, 1:13 PM EST	Severe Thunderstorm Watch	SPC	Caroline, Cecil, Dorchester, Kent, Queen Anne's, Somerset and 3 more	4 hr
Mar 1, 2:50 PM EST	Mesoscale Discussion	SPC	Caroline, Cecil, Dorchester, Queen Anne's, Somerset, Talbot and 2 more	55 min
Mar 1, 12:48 PM EST	Tornado Watch	SPC	Cherokee, Clay	6 hr
Mar 1, 2:07 PM EST	Mesoscale Discussion	SPC	Alexander, Buncombe, Burke, Cabarrus, Catawba, Cleveland and 16 more	113 min
Mar 1, 3:02 PM EST	Severe Thunderstorm Watch	SPC	Alamance, Alexander, Anson, Avery, Buncombe, Burke and 43 more	7 hr
Mar 1, 6:21 PM EST	Mesoscale Discussion	SPC	Alamance, Anson, Beaufort, Bertie, Bladen, Cabarrus and 40 more	114 min
Mar 1, 2:19 AM EST	Mesoscale Discussion	SPC	Allegheny, Armstrong, Beaver, Butler, Cambria, Clarion and 13 more	86 min
Mar 1, 3:56 PM EST	Mesoscale Discussion	SPC	Beaver, Butler, Crawford, Lawrence, Mercer, Venango and 1 more	2 hr
Mar 1, 6:28 AM EST	Mesoscale Discussion	SPC	Dickenson, Lee, Wise	2 hr
Mar 1, 7:47 AM EST	Severe Thunderstorm Watch	SPC	Buchanan, Dickenson, Lee, Russell, Scott, Washington and 3 more	5 hr
Mar 1, 8:28 AM EST	Mesoscale Discussion	SPC	Buchanan, Dickenson, Lee, Russell, Scott, Tazewell and 2 more	92 min
Mar 1, 2:32 AM EST	Mesoscale Discussion	SPC	Boone, Cabell, Calhoun, Clay, Fayette, Jackson and 12 more	88 min
Mar 1, 6:48 AM EST	Severe Thunderstorm Watch	SPC	Barbour, Braxton, Cabell, Calhoun, Clay, Doddridge and 19 more	5 hr

Nearby

Mesoscale Discussions in Virginia, 2017 Mesoscale Discussions in Maryland, 2017 Mesoscale Discussions in Pennsylvania, 2017 Every mesoscale discussion in 2017

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.