Alert archive / North Carolina / Mesoscale Discussions in 2021
Mesoscale Discussion 976
The Storm Prediction Center issued this mesoscale discussion at Jun 15, 2021, 12:57 PM EDT for Richmond County, Georgia; 36 counties in North Carolina; 30 counties in South Carolina. It was in force for 63 min.
The area
The outline as issued.
The facts
- Issued
- Jun 15, 2021, 12:57 PM EDT (16:57 UTC)
- Expired
- Jun 15, 2021, 2:00 PM EDT
- In force
- 63 min
- Issued by
- the Storm Prediction Center
- Concerning
- Severe potential...severe thunderstorm watch likely
- Chance of a watch
- 80%
All 67 counties
Richmond County, GA, Anson County, NC, Beaufort County, NC, Bertie County, NC, Bladen County, NC, Brunswick County, NC, Carteret County, NC, Chowan County, NC, Columbus County, NC, Craven County, NC, Cumberland County, NC, Duplin County, NC, Edgecombe County, NC, Greene County, NC, Harnett County, NC, Hoke County, NC, Hyde County, NC, Johnston County, NC, Jones County, NC, Lee County, NC, Lenoir County, NC, Martin County, NC, Nash County, NC, New Hanover County, NC, Onslow County, NC, Pamlico County, NC, Pender County, NC, Pitt County, NC, Richmond County, NC, Robeson County, NC, Sampson County, NC, Scotland County, NC, Tyrrell County, NC, Wake County, NC, Washington County, NC, Wayne County, NC, Wilson County, NC, Aiken County, SC, Allendale County, SC, Bamberg County, SC, Barnwell County, SC, Berkeley County, SC, Calhoun County, SC, Charleston 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, Georgetown County, SC, Hampton County, SC, Horry County, SC, Kershaw County, SC, Lancaster County, SC, Lee County, SC, Lexington County, SC, Marion County, SC, Marlboro County, SC, Orangeburg County, SC, Richland County, SC, Saluda County, SC, Sumter County, SC, Williamsburg County, SC
The radar
The Wilmington radar (KLTX), 45 km from the middle of the area, began a volume at 16:57 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
Charleston AFB, SC (KCHS), launched 12:00Z, 5.0 hours before the alert went out and 169 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.
- Mixed-layer CAPE
- 1323 J/kg
- Mixed-layer CIN
- -80 J/kg
- Mixed-layer LCL
- 1170 m above ground
- 0-6 km bulk shear
- 9 kt
- 0-1 km storm-relative helicity
- 17 m²/s²
- 0-3 km storm-relative helicity
- 16 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
809
ACUS11 KWNS 151657
SWOMCD
SPC MCD 151657
NCZ000-SCZ000-GAZ000-151800-
Mesoscale Discussion 0976
NWS Storm Prediction Center Norman OK
1157 AM CDT Tue Jun 15 2021
Areas affected...Portions of central and eastern South Carolina into
eastern North Carolina
Concerning...Severe potential...Severe Thunderstorm Watch likely
Valid 151657Z - 151800Z
Probability of Watch Issuance...80 percent
SUMMARY...The risk of strong to potentially severe thunderstorms is
gradually increasing. Damaging gusts and large hail appear to be the
primary threats. A Severe Thunderstorm Watch will likely be needed
by around 18Z.
DISCUSSION...Temperatures are warming into the upper 80s to near 90F
ahead of a cold front given strong surface heating. The warm surface
temperatures and 70+ F dewpoints are contributing to 2000 J/kg
MLCAPE along Carolina Coastal Plain given 6-6.5 C/km mid-level lapse
rates. Latest visible satellite is showing the development of a CU
field ahead of the surface lee trough axis, with convection expected
to initiate within the next couple of hours as a 50 kt 500 mb speed
max approaches the Atlantic Coastline. As the speed max overspreads
the region, 40-50 kts of effective bulk shear, combined with the
2000 J/kg MLCAPE will both foster an environment favorable for
multicellular clusters and perhaps transient supercells to develop
immediately ahead of the cold front. The storms may produce damaging
gusts (given 8+ C/km low-level lapse rates) and perhaps some large
hail, particularly with the stronger cellular storms before moving
offshore. Severe wind/hail coverage is expected to be high enough to
warrant a Severe Thunderstorm Watch issuance within the next hour.
..Squitieri/Grams.. 06/15/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...AKQ...MHX...RAH...ILM...CHS...CAE...GSP...
LAT...LON 32378025 32458097 32598132 32848174 33518225 34168176
35367939 35997831 36247717 36227659 35967618 35527568
35417558 34607627 33947742 33317845 32867919 32398015
32378025SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 15, 1:33 PM EDT | Mesoscale Discussion | SPC | Charlton, Clinch, Echols, Lowndes, Ware | 2 hr |
| Jun 15, 1:58 PM EDT | Severe Thunderstorm Watch | SPC | Beaufort, Bladen, Brunswick, Carteret, Columbus, Craven and 12 more | 7 hr |
| Jun 15, 4:09 PM EDT | Mesoscale Discussion | SPC | Beaufort, Bladen, Brunswick, Carteret, Columbus, Craven and 10 more | 96 min |
Nearby
Mesoscale Discussions in North Carolina, 2021Mesoscale Discussions in South 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.