Alert archive / North Carolina / Mesoscale Discussions in 2009

Mesoscale Discussion 705

May 4, 200930 counties in North Carolina; Georgetown County, Horry County, South Carolina

The Storm Prediction Center issued this mesoscale discussion at May 4, 2009, 9:08 PM EDT for 30 counties in North Carolina; Georgetown County, Horry County, South Carolina. It was in force for 97 min.

The area

The outline as issued.

The facts

Issued: May 4, 2009, 9:08 PM EDT (01:08 UTC)
Expired: May 4, 2009, 10:45 PM EDT
In force: 97 min
Issued by: the Storm Prediction Center

All 32 counties

Beaufort County, NC, Bertie County, NC, Bladen County, NC, Brunswick County, NC, Chowan County, NC, Columbus County, NC, Craven County, NC, Duplin County, NC, Edgecombe County, NC, Gates County, NC, Greene County, NC, Halifax County, NC, Hertford 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, Pender County, NC, Perquimans County, NC, Pitt County, NC, Sampson County, NC, Tyrrell County, NC, Warren County, NC, Washington County, NC, Wayne County, NC, Wilson County, NC, Georgetown County, SC, Horry County, SC

The radar

The Raleigh/Durham radar (KRAX), 86 km from the middle of the area, began a volume at 01:11 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 00:00Z, 1.1 hours before the alert went out and 103 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: 913 J/kg
Mixed-layer CIN: -46 J/kg
Mixed-layer LCL: 854 m above ground
0-6 km bulk shear: 28 kt
0-1 km storm-relative helicity: 60 m²/s²
0-3 km storm-relative helicity: 91 m²/s²
Significant tornado parameter: 0.2
Supercell composite: 1.8

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 5, 9:43 AM EDT	Mesoscale Discussion	SPC	Beaufort, Bladen, Brunswick, Carteret, Columbus, Craven and 6 more	92 min
May 5, 10:18 AM EDT	Severe Thunderstorm Watch	SPC	Bladen, Brunswick, Columbus, Cumberland, Duplin, New Hanover and 4 more	8 hr
May 5, 2:03 PM EDT	Mesoscale Discussion	SPC	Bladen, Brunswick, Columbus, Pender, Robeson, Sampson	87 min
May 5, 4:35 PM EDT	Mesoscale Discussion	SPC	Craven, Greene, Lenoir, Pamlico, Wayne	55 min
May 5, 5:37 PM EDT	Mesoscale Discussion	SPC	Bladen, Brunswick, Chatham, Columbus, Craven, Cumberland and 23 more	53 min
May 5, 5:45 PM EDT	Tornado Watch	SPC	Anson, Beaufort, Bertie, Bladen, Cabarrus, Camden and 45 more	5 hr
May 5, 7:10 PM EDT	Mesoscale Discussion	SPC	Alamance, Anson, Bertie, Cabarrus, Camden, Chatham and 41 more	65 min

Nearby

Mesoscale Discussions in North Carolina, 2009 Mesoscale Discussions in South Carolina, 2009 Every mesoscale discussion in 2009

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.