Alert archive / North Carolina / Mesoscale Discussions in 2014

Mesoscale Discussion 402

April 25, 201454 counties in North Carolina; 41 counties in Virginia

The Storm Prediction Center issued this mesoscale discussion at Apr 25, 2014, 12:46 PM EDT for 54 counties in North Carolina; 41 counties in Virginia. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued: Apr 25, 2014, 12:46 PM EDT (16:46 UTC)
Expired: Apr 25, 2014, 3:15 PM EDT
In force: 2 hr
Issued by: the Storm Prediction Center
Chance of a watch: 80%

All 95 counties

Alamance County, NC, Beaufort County, NC, Bertie County, NC, Bladen County, NC, Camden County, NC, Carteret County, NC, Caswell County, NC, Chatham County, NC, Chowan County, NC, Craven County, NC, Cumberland County, NC, Currituck County, NC, Dare County, NC, Duplin County, NC, Durham County, NC, Edgecombe County, NC, Franklin County, NC, Gates County, NC, Granville County, NC, Greene County, NC, Guilford County, NC, Halifax County, NC, Harnett County, NC, Hertford County, NC, Hoke County, NC, Hyde County, NC, Johnston County, NC, Jones County, NC, Lee County, NC, Lenoir County, NC, Martin County, NC, Montgomery County, NC, Moore County, NC, Nash County, NC, Northampton County, NC, Onslow County, NC, Orange County, NC, Pamlico County, NC, Pasquotank County, NC, Pender County, NC, Perquimans County, NC, Person County, NC, Pitt County, NC, Randolph County, NC, Rockingham County, NC, Sampson County, NC, Stokes County, NC, Tyrrell County, NC, Vance County, NC, Wake County, NC, Warren County, NC, Washington County, NC, Wayne County, NC, Wilson County, NC, Amelia County, VA, Appomattox County, VA, Brunswick County, VA, Campbell County, VA, Charles City County, VA, Charlotte County, VA, Chesterfield County, VA, City of Chesapeake, VA, City of Colonial Heights, VA, City of Danville, VA, City of Emporia, VA, City of Franklin, VA, City of Hampton, VA, City of Hopewell, VA, City of Martinsville, VA, City of Newport News, VA, City of Norfolk, VA, City of Petersburg, VA, City of Poquoson, VA, City of Portsmouth, VA, City of Suffolk, VA, City of Virginia Beach, VA, City of Williamsburg, VA, Dinwiddie County, VA, Franklin County, VA, Greensville County, VA, Halifax County, VA, Henrico County, VA, Henry County, VA, Isle of Wight County, VA, James City County, VA, Lunenburg County, VA, Mecklenburg County, VA, Nottoway County, VA, Pittsylvania County, VA, Prince Edward County, VA, Prince George County, VA, Southampton County, VA, Surry County, VA, Sussex County, VA, York County, VA

The radar

The Raleigh/Durham radar (KRAX), 77 km from the middle of the area, began a volume at 16:49 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.

Tornado Watch 91Apr 25, 1:20 PM EDT

The nearest sounding before it

Newport, NC (KMHX), launched 12:00Z, 4.8 hours before the alert went out and 149 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: 100 J/kg
Mixed-layer CIN: -17 J/kg
Mixed-layer LCL: 667 m above ground
0-6 km bulk shear: 26 kt
0-1 km storm-relative helicity: 125 m²/s²
0-3 km storm-relative helicity: 109 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
Apr 25, 1:19 PM EDT	Tornado Watch	SPC	Alamance, Anson, Beaufort, Bertie, Camden, Carteret and 51 more	10 hr
Apr 25, 3:22 PM EDT	Mesoscale Discussion	SPC	Alamance, Anson, Beaufort, Bertie, Camden, Caswell and 46 more	83 min
Apr 25, 4:45 PM EDT	Mesoscale Discussion	SPC	Alamance, Beaufort, Bertie, Camden, Carteret, Caswell and 47 more	90 min
Apr 25, 7:29 PM EDT	Mesoscale Discussion	SPC	Beaufort, Bertie, Camden, Carteret, Chowan, Craven and 24 more	61 min
Apr 25, 2:50 PM EDT	Mesoscale Discussion	SPC	Accomack, Albemarle, Buckingham, Caroline, Culpeper, Cumberland and 25 more	2 hr

Nearby

Mesoscale Discussions in North Carolina, 2014 Mesoscale Discussions in Virginia, 2014 Every mesoscale discussion in 2014

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.