Alert archive / South Carolina / Mesoscale Discussions in 2017

Mesoscale Discussion 305

March 21, 201723 counties in Georgia; 32 counties in South Carolina

The Storm Prediction Center issued this mesoscale discussion at Mar 21, 2017, 7:47 PM EDT for 23 counties in Georgia; 32 counties in South Carolina. It was in force for 58 min.

The area

The outline as issued.

The facts

Issued
Mar 21, 2017, 7:47 PM EDT (23:47 UTC)
Expired
Mar 21, 2017, 8:45 PM EDT
In force
58 min
Issued by
the Storm Prediction Center
Chance of a watch
95%
All 55 counties

Burke County, GA, Clarke County, GA, Columbia County, GA, Elbert County, GA, Glascock County, GA, Greene County, GA, Hancock County, GA, Hart County, GA, Jefferson County, GA, Jenkins County, GA, Lincoln County, GA, Madison County, GA, McDuffie County, GA, Morgan County, GA, Oconee County, GA, Oglethorpe County, GA, Putnam County, GA, Richmond County, GA, Screven County, GA, Taliaferro County, GA, Walton County, GA, Warren County, GA, Wilkes County, GA, Abbeville County, SC, Aiken County, SC, Allendale County, SC, Anderson County, SC, Bamberg County, SC, Barnwell County, SC, Calhoun County, SC, Cherokee County, SC, Chester County, SC, Chesterfield County, SC, Clarendon County, SC, Darlington County, SC, Edgefield County, SC, Fairfield County, SC, Florence County, SC, Greenville County, SC, Greenwood County, SC, Hampton County, SC, Kershaw County, SC, Lancaster County, SC, Laurens County, SC, Lee County, SC, Lexington County, SC, McCormick County, SC, Newberry County, SC, Orangeburg County, SC, Richland County, SC, Saluda County, SC, Spartanburg County, SC, Sumter County, SC, Union County, SC, York County, SC

The radar

The Columbia radar (KCAE), 68 km from the middle of the area, began a volume at 23:49 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

Peachtre/Fal Fld, GA (KFFC), launched 12:00Z, 11.8 hours before the alert went out and 252 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, Peachtre/Fal Fld, GA at 12:00Z on 2017-03-21Temperature 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, Peachtre/Fal Fld, GA at 12:00Z on 2017-03-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 125 square meters per square second.1939Sfc1 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
1219 m above ground
0-6 km bulk shear
25 kt
0-1 km storm-relative helicity
125 m²/s²
0-3 km storm-relative helicity
152 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

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SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Mar 21, 2:53 PM EDTMesoscale DiscussionSPCBanks, Barrow, Bartow, Carroll, Catoosa, Chattooga and 44 more3 hr
Mar 21, 3:33 PM EDTSevere Thunderstorm WatchSPCBanks, Barrow, Bartow, Carroll, Catoosa, Chattooga and 48 more7 hr
Mar 21, 5:30 PM EDTMesoscale DiscussionSPCCatoosa, Dade, Walker, Whitfield90 min

Nearby

Mesoscale Discussions in South Carolina, 2017Mesoscale Discussions in Georgia, 2017Every mesoscale discussion in 2017

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.