Alert archive / North Carolina / Mesoscale Discussions in 2008

Mesoscale Discussion 952

May 20, 200813 counties in North Carolina; 11 counties in South Carolina

The Storm Prediction Center issued this mesoscale discussion at May 20, 2008, 3:23 PM EDT for 13 counties in North Carolina; 11 counties in South Carolina. It was in force for 37 min.

The area

The outline as issued.

The facts

Issued: May 20, 2008, 3:23 PM EDT (19:23 UTC)
Expired: May 20, 2008, 4:00 PM EDT
In force: 37 min
Issued by: the Storm Prediction Center

All 24 counties

Bladen County, NC, Brunswick County, NC, Columbus County, NC, Craven County, NC, Duplin County, NC, Greene County, NC, Jones County, NC, Lenoir County, NC, New Hanover County, NC, Onslow County, NC, Pender County, NC, Pitt County, NC, Sampson County, NC, Allendale County, SC, Berkeley County, SC, Charleston County, SC, Clarendon County, SC, Colleton County, SC, Dorchester County, SC, Florence County, SC, Georgetown County, SC, Horry County, SC, Marion County, SC, Williamsburg County, SC

The radar

The Wilmington radar (KLTX), 86 km from the middle of the area, began a volume at 19:22 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 329May 20, 3:40 PM EDT

The nearest sounding before it

Charleston AFB, SC (KCHS), launched 12:00Z, 7.4 hours before the alert went out and 116 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: 621 J/kg
Mixed-layer CIN: -224 J/kg
Mixed-layer LCL: 1344 m above ground
0-6 km bulk shear: 44 kt
0-1 km storm-relative helicity: 100 m²/s²
0-3 km storm-relative helicity: 94 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
May 20, 12:34 PM EDT	Mesoscale Discussion	SPC	Caswell, Northampton, Person, Vance, Warren	56 min
May 20, 1:09 PM EDT	Severe Thunderstorm Watch	SPC	Alamance, Alexander, Alleghany, Anson, Bertie, Burke and 54 more	7 hr
May 20, 2:59 PM EDT	Severe Thunderstorm Watch	SPC	Avery, Buncombe, Cherokee, Clay, Graham, Haywood and 11 more	7 hr
May 20, 3:39 PM EDT	Tornado Watch	SPC	Beaufort, Bladen, Brunswick, Carteret, Columbus, Craven and 15 more	7 hr
May 20, 4:38 PM EDT	Mesoscale Discussion	SPC	Alamance, Bertie, Cabarrus, Camden, Chatham, Chowan and 22 more	67 min
May 20, 7:19 PM EDT	Mesoscale Discussion	SPC	Anson, Hoke, Richmond, Scotland, Union	86 min
May 20, 2:23 PM EDT	Mesoscale Discussion	SPC	Aiken, Allendale, Bamberg, Barnwell, Calhoun, Clarendon and 10 more	67 min

Nearby

Mesoscale Discussions in North Carolina, 2008 Mesoscale Discussions in South Carolina, 2008 Every mesoscale discussion in 2008

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.