Alert archive / North Carolina / Mesoscale Discussions in 2014

Mesoscale Discussion 1479

July 27, 201434 counties in North Carolina; 5 counties in Virginia

The Storm Prediction Center issued this mesoscale discussion at Jul 27, 2014, 10:08 AM EDT for 34 counties in North Carolina; 5 counties in Virginia. It was in force for 67 min.

The area

The outline as issued.

The facts

Issued: Jul 27, 2014, 10:08 AM EDT (14:08 UTC)
Expired: Jul 27, 2014, 11:15 AM EDT
In force: 67 min
Issued by: the Storm Prediction Center
Chance of a watch: 40%

All 39 counties

Beaufort County, NC, Bertie County, NC, Bladen County, NC, Camden County, NC, Chowan County, NC, Craven County, NC, Cumberland County, NC, Duplin County, NC, Edgecombe County, NC, Franklin County, NC, Gates County, NC, Greene County, NC, Halifax County, NC, Harnett County, NC, Hertford County, NC, Johnston County, NC, Jones County, NC, Lenoir County, NC, Martin County, NC, Nash County, NC, Northampton County, NC, Onslow County, NC, Pamlico County, NC, Pasquotank County, NC, Perquimans County, NC, Pitt County, NC, Sampson County, NC, Tyrrell County, NC, Vance County, NC, Wake County, NC, Warren County, NC, Washington County, NC, Wayne County, NC, Wilson County, NC, City of Emporia, VA, City of Franklin, VA, City of Suffolk, VA, Greensville County, VA, Southampton County, VA

The radar

The Raleigh/Durham radar (KRAX), 83 km from the middle of the area, began a volume at 14:09 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

Newport, NC (KMHX), launched 12:00Z, 2.1 hours before the alert went out and 121 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: 1931 J/kg
Mixed-layer CIN: -25 J/kg
Mixed-layer LCL: 944 m above ground
0-6 km bulk shear: 20 kt
0-1 km storm-relative helicity: 41 m²/s²
0-3 km storm-relative helicity: 46 m²/s²
Significant tornado parameter: 0.3
Supercell composite: 2.3

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
Jul 27, 4:49 PM EDT	Mesoscale Discussion	SPC	Alexander, Alleghany, Ashe, Avery, Burke, Caldwell and 13 more	116 min
Jul 27, 6:32 PM EDT	Tornado Watch	SPC	Alexander, Alleghany, Ashe, Avery, Buncombe, Burke and 27 more	6 hr
Jul 27, 1:00 PM EDT	Tornado Watch	SPC	Buchanan, Dickenson, Lee, Russell, Scott, Washington and 3 more	11 hr
Jul 27, 3:14 PM EDT	Mesoscale Discussion	SPC	Dickenson, Lee, Russell, Scott, Wise, City of Bristol and 1 more	2 hr
Jul 27, 6:52 PM EDT	Severe Thunderstorm Watch	SPC	Clarke, Frederick, Shenandoah, Warren, City of Winchester	7 hr
Jul 27, 7:28 PM EDT	Mesoscale Discussion	SPC	Dickenson, Lee, Russell, Scott, Washington, Wise and 2 more	92 min

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.