Alert archive / North Carolina / Mesoscale Discussions in 2014

Mesoscale Discussion 476

April 29, 201446 counties in North Carolina; Chesterfield County, Lancaster County, Marlboro County, South Carolina; Henry County, City of Danville, City of Martinsville, Virginia

The Storm Prediction Center issued this mesoscale discussion at Apr 29, 2014, 1:26 PM EDT for 46 counties in North Carolina; Chesterfield County, Lancaster County, Marlboro County, South Carolina; Henry County, City of Danville, City of Martinsville, Virginia. It was in force for 94 min.

The area

The outline as issued.

The facts

Issued
Apr 29, 2014, 1:26 PM EDT (17:26 UTC)
Expired
Apr 29, 2014, 3:00 PM EDT
In force
94 min
Issued by
the Storm Prediction Center
Chance of a watch
60%
All 52 counties

Alamance County, NC, Anson County, NC, Bladen County, NC, Cabarrus County, NC, Caswell County, NC, Catawba County, NC, Chatham County, NC, Cumberland County, NC, Davidson County, NC, Davie County, NC, Duplin County, NC, Durham County, NC, Forsyth County, NC, Franklin County, NC, Gaston County, NC, Granville County, NC, Guilford County, NC, Harnett County, NC, Hoke County, NC, Iredell County, NC, Johnston County, NC, Lee County, NC, Lincoln County, NC, Mecklenburg County, NC, Montgomery County, NC, Moore County, NC, Nash County, NC, Orange County, NC, Person County, NC, Randolph County, NC, Richmond County, NC, Robeson County, NC, Rockingham County, NC, Rowan County, NC, Sampson County, NC, Scotland County, NC, Stanly County, NC, Stokes County, NC, Surry County, NC, Union County, NC, Vance County, NC, Wake County, NC, Warren County, NC, Wayne County, NC, Wilson County, NC, Yadkin County, NC, Chesterfield County, SC, Lancaster County, SC, Marlboro County, SC, City of Danville, VA, City of Martinsville, VA, Henry County, VA

The radar

The Raleigh/Durham radar (KRAX), 82 km from the middle of the area, began a volume at 17:28 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

Greensboro/Hi Pt, NC (KGSO), launched 12:00Z, 5.4 hours before the alert went out and 83 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, Greensboro/Hi Pt, NC at 12:00Z on 2014-04-29Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Greensboro/Hi Pt, NC at 12:00Z on 2014-04-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 478 square meters per square second.19395878Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
701 m above ground
0-6 km bulk shear
50 kt
0-1 km storm-relative helicity
478 m²/s²
0-3 km storm-relative helicity
540 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
Apr 28, 10:34 PM EDTMesoscale DiscussionSPCCherokee, Graham86 min
Apr 28, 11:29 PM EDTMesoscale DiscussionSPCBuncombe, Clay, Haywood, Henderson, Jackson, Macon and 2 more61 min
Apr 29, 12:20 AM EDTMesoscale DiscussionSPCCherokee, Clay, Graham, Haywood, Jackson, Macon and 1 more85 min
Apr 29, 12:30 AM EDTTornado WatchSPCBuncombe, Cherokee, Clay, Graham, Haywood, Henderson and 10 more7 hr
Apr 29, 2:27 PM EDTTornado WatchSPCAnson, Beaufort, Bertie, Carteret, Chatham, Chowan and 38 more8 hr
Apr 29, 4:38 PM EDTMesoscale DiscussionSPCBeaufort, Bertie, Bladen, Camden, Carteret, Chowan and 27 more97 min
Apr 29, 7:22 PM EDTMesoscale DiscussionSPCBeaufort, Bertie, Carteret, Chowan, Craven, Cumberland and 26 more53 min

Nearby

Mesoscale Discussions in North Carolina, 2014Mesoscale Discussions in South Carolina, 2014Mesoscale Discussions in Virginia, 2014Every 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.