Alert archive / North Carolina / Mesoscale Discussions in 2021
Mesoscale Discussion 1377
The Storm Prediction Center issued this mesoscale discussion at Jul 28, 2021, 6:07 PM EDT for 14 counties in North Carolina; 9 counties in South Carolina. It was in force for 83 min.
The area
The outline as issued.
The facts
- Issued
- Jul 28, 2021, 6:07 PM EDT (22:07 UTC)
- Expired
- Jul 28, 2021, 7:30 PM EDT
- In force
- 83 min
- Issued by
- the Storm Prediction Center
- Concerning
- Severe potential...watch unlikely
- Chance of a watch
- 20%
All 23 counties
Anson County, NC, Bladen County, NC, Brunswick County, NC, Columbus County, NC, Cumberland County, NC, Duplin County, NC, Hoke County, NC, New Hanover County, NC, Pender County, NC, Richmond County, NC, Robeson County, NC, Sampson County, NC, Scotland County, NC, Union County, NC, Chesterfield County, SC, Darlington County, SC, Dillon County, SC, Florence County, SC, Georgetown County, SC, Horry County, SC, Marion County, SC, Marlboro County, SC, Williamsburg County, SC
The radar
The Wilmington radar (KLTX), 70 km from the middle of the area, began a volume at 22:08 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 12:00Z, 10.1 hours before the alert went out and 209 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
- 2446 J/kg
- Mixed-layer CIN
- -4 J/kg
- Mixed-layer LCL
- 613 m above ground
- 0-6 km bulk shear
- 21 kt
- 0-1 km storm-relative helicity
- 61 m²/s²
- 0-3 km storm-relative helicity
- 44 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 1.0
The text
As transmitted.
179
ACUS11 KWNS 282207
SWOMCD
SPC MCD 282207
NCZ000-SCZ000-282330-
Mesoscale Discussion 1377
NWS Storm Prediction Center Norman OK
0507 PM CDT Wed Jul 28 2021
Areas affected...Southern North Carolina and northern South Carolina
Concerning...Severe potential...Watch unlikely
Valid 282207Z - 282330Z
Probability of Watch Issuance...20 percent
SUMMARY...An isolated damaging wind and large hail threat will
continue south of watch 398. No additional watch is expected.
DISCUSSION...Several strong to severe storms have developed south of
watch 398. MLCAPE around 2000 to 2500 J/kg and effective shear
around 30 knots will continue to support some storm organization and
an isolated severe threat. However, a cooling boundary layer through
the evening and weaker mid-level flow with southern extent should
result in a less supportive severe weather environment through the
evening. Therefore, while some isolated severe weather is possible,
the limited duration of the threat precludes the need for an
additional watch.
..Bentley/Goss.. 07/28/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...MHX...RAH...ILM...CAE...GSP...
LAT...LON 35277914 35097807 34487721 34157776 33767795 33797844
33617885 33407904 33317916 33647977 34118021 34558048
34978056 35038056 35277914SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 28, 12:36 PM EDT | Mesoscale Discussion | SPC | Beaufort, Bertie, Bladen, Camden, Chowan, Craven and 28 more | 114 min |
| Jul 28, 2:19 PM EDT | Severe Thunderstorm Watch | SPC | Beaufort, Bertie, Camden, Carteret, Chowan, Craven and 29 more | 6 hr |
| Jul 28, 4:16 PM EDT | Mesoscale Discussion | SPC | Beaufort, Bertie, Camden, Chowan, Craven, Cumberland and 23 more | 119 min |
Nearby
Mesoscale Discussions in North Carolina, 2021Mesoscale Discussions in South Carolina, 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.