Alert archive / South Carolina / Mesoscale Discussions in 2021

Mesoscale Discussion 224

March 18, 2021Elbert County, Georgia; 8 counties in North Carolina; 14 counties in South Carolina

The Storm Prediction Center issued this mesoscale discussion at Mar 18, 2021, 3:10 PM EDT for Elbert County, Georgia; 8 counties in North Carolina; 14 counties in South Carolina. It was in force for 3 hr.

The area

The outline as issued.

The facts

Issued
Mar 18, 2021, 3:10 PM EDT (19:10 UTC)
Expired
Mar 18, 2021, 5:45 PM EDT
In force
3 hr
Issued by
the Storm Prediction Center
Concerning
Tornado watch 41
All 23 counties

Elbert County, GA, Cabarrus County, NC, Cleveland County, NC, Gaston County, NC, Lincoln County, NC, Mecklenburg County, NC, Rutherford County, NC, Stanly County, NC, Union County, NC, Abbeville County, SC, Anderson County, SC, Cherokee County, SC, Chester County, SC, Fairfield County, SC, Greenville County, SC, Greenwood County, SC, Lancaster County, SC, Laurens County, SC, Newberry County, SC, Saluda County, SC, Spartanburg County, SC, Union County, SC, York County, SC

The radar

The Columbia radar (KCAE), 72 km from the middle of the area, began a volume at 19:10 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, 7.2 hours before the alert went out and 217 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, Greensboro/Hi Pt, NC at 12:00Z on 2021-03-18Temperature 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, Greensboro/Hi Pt, NC at 12:00Z on 2021-03-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 470 square meters per square second.19395878Sfc1 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
486 m above ground
0-6 km bulk shear
67 kt
0-1 km storm-relative helicity
470 m²/s²
0-3 km storm-relative helicity
562 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

212 
ACUS11 KWNS 181911
SWOMCD
SPC MCD 181910 
NCZ000-SCZ000-GAZ000-182145-

Mesoscale Discussion 0224
NWS Storm Prediction Center Norman OK
0210 PM CDT Thu Mar 18 2021

Areas affected...northern South Carolina into central North Carolina

Concerning...Tornado Watch 41...

Valid 181910Z - 182145Z

The severe weather threat for Tornado Watch 41 continues.

SUMMARY...Storms will continue to develop east/northeast across the
watch area, and a new watch could be needed into central North
Carolina later this afternoon.

DISCUSSION...A broken line of cells continues to progress east into
northwestern SC, near the surface trough and along and north of the
warm front. Surface analysis shows warming and destabilization
continues south of this front, and this should allow these storms to
persist and perhaps expand in coverage. The greatest severe risk
appears to be along the warm front, where storms will experience
enhanced lift. Strong deep-layer shear as well as effective SRH of
200-300 m2/s2 will favor supercells at times, with a threat of a
brief tornado or damaging gusts. If storm trends continue up over
the next few hours, an additional watch could be needed downstream
into NC.

..Jewell.. 03/18/2021

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...RAH...CAE...GSP...FFC...

LAT...LON   33928101 33918311 35518200 35517986 33928101

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Mar 17, 11:15 PM EDTMesoscale DiscussionSPCQuitman90 min
Mar 18, 12:02 AM EDTTornado WatchSPCBaker, Bibb, Butts, Calhoun, Carroll, Chattahoochee and 38 more9 hr
Mar 18, 2:52 AM EDTMesoscale DiscussionSPCChattahoochee, Clay, Marion, Quitman, Randolph, Stewart and 1 more83 min
Mar 18, 5:28 AM EDTMesoscale DiscussionSPCClay, Early, Seminole92 min
Mar 18, 7:32 AM EDTMesoscale DiscussionSPCAtkinson, Baker, Ben Hill, Berrien, Brooks, Calhoun and 28 more58 min
Mar 18, 7:53 AM EDTTornado WatchSPCBaker, Ben Hill, Berrien, Bleckley, Brooks, Calhoun and 32 more5 hr
Mar 18, 10:34 AM EDTMesoscale DiscussionSPCBanks, Barrow, Clarke, Elbert, Franklin, Habersham and 5 more2 hr
Mar 18, 11:05 AM EDTMesoscale DiscussionSPCAppling, Atkinson, Bacon, Ben Hill, Berrien, Brantley and 37 more115 min
Mar 18, 11:42 AM EDTTornado WatchSPCAppling, Atkinson, Bacon, Brantley, Bryan, Bulloch and 21 more6 hr
Mar 18, 2:08 PM EDTTornado WatchSPCElbert, Lincoln4 hr
Mar 18, 4:45 PM EDTTornado WatchSPCAlamance, Anson, Chatham, Cumberland, Davidson, Durham and 20 more4 hr
Mar 18, 5:09 PM EDTTornado WatchSPCBertie, Camden, Chowan, Currituck, Gates, Hertford and 3 more6 hr
Mar 18, 5:57 PM EDTMesoscale DiscussionSPCAlamance, Anson, Beaufort, Bertie, Cabarrus, Camden and 45 more63 min
Mar 18, 7:49 PM EDTMesoscale DiscussionSPCAlamance, Anson, Chatham, Cumberland, Durham, Edgecombe and 21 more56 min

Nearby

Mesoscale Discussions in South Carolina, 2021Mesoscale Discussions in North Carolina, 2021Mesoscale Discussions in Georgia, 2021Every mesoscale discussion in 2021

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.