Alert archive / South Carolina / Mesoscale Discussions in 2009

Mesoscale Discussion 1602

July 17, 20094 counties in Georgia; 6 counties in North Carolina; 33 counties in South Carolina

The Storm Prediction Center issued this mesoscale discussion at Jul 17, 2009, 4:28 PM EDT for 4 counties in Georgia; 6 counties in North Carolina; 33 counties in South Carolina. It was in force for 92 min.

The area

The outline as issued.

The facts

Issued: Jul 17, 2009, 4:28 PM EDT (20:28 UTC)
Expired: Jul 17, 2009, 6:00 PM EDT
In force: 92 min
Issued by: the Storm Prediction Center

All 43 counties

Burke County, GA, Columbia County, GA, Lincoln County, GA, Richmond County, GA, Anson County, NC, Mecklenburg County, NC, Richmond County, NC, Robeson County, NC, Scotland County, NC, Union County, NC, Aiken County, SC, Allendale County, SC, Bamberg County, SC, Barnwell County, SC, Berkeley County, SC, Calhoun County, SC, Chester County, SC, Chesterfield County, SC, Clarendon County, SC, Colleton County, SC, Darlington County, SC, Dillon County, SC, Dorchester County, SC, Edgefield County, SC, Fairfield County, SC, Florence County, SC, Greenwood County, SC, Hampton County, SC, Kershaw County, SC, Lancaster County, SC, Lee County, SC, Lexington County, SC, Marion County, SC, Marlboro County, SC, McCormick County, SC, Newberry County, SC, Orangeburg County, SC, Richland County, SC, Saluda County, SC, Sumter County, SC, Union County, SC, Williamsburg County, SC, York County, SC

The radar

The Columbia radar (KCAE), 21 km from the middle of the area, began a volume at 20:32 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

Greensboro/Hi Pt, NC (KGSO), launched 12:00Z, 8.5 hours before the alert went out and 257 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: 1664 J/kg
Mixed-layer CIN: -31 J/kg
Mixed-layer LCL: 866 m above ground
0-6 km bulk shear: 43 kt
0-1 km storm-relative helicity: -1 m²/s²
0-3 km storm-relative helicity: 5 m²/s²
Significant tornado parameter: 0.2
Supercell composite: 1.1

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 17, 9:52 AM EDT	Mesoscale Discussion	SPC	Alamance, Caswell, Chatham, Davidson, Durham, Edgecombe and 18 more	83 min
Jul 17, 10:29 AM EDT	Severe Thunderstorm Watch	SPC	Alamance, Caswell, Chatham, Davidson, Durham, Forsyth and 11 more	7 hr
Jul 17, 12:59 PM EDT	Mesoscale Discussion	SPC	Alamance, Caswell, Chatham, Durham, Granville, Guilford and 5 more	91 min
Jul 17, 2:00 PM EDT	Tornado Watch	SPC	Bertie, Camden, Chowan, Currituck, Gates, Hertford and 3 more	5 hr
Jul 17, 2:42 PM EDT	Severe Thunderstorm Watch	SPC	Beaufort, Carteret, Craven, Cumberland, Dare, Duplin and 21 more	7 hr
Jul 17, 3:41 PM EDT	Mesoscale Discussion	SPC	Gates, Hertford, Northampton	94 min
Jul 17, 6:45 PM EDT	Mesoscale Discussion	SPC	Beaufort, Cumberland, Duplin, Greene, Hoke, Johnston and 7 more	60 min

Nearby

Mesoscale Discussions in South Carolina, 2009 Mesoscale Discussions in North Carolina, 2009 Mesoscale Discussions in Georgia, 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.