Alert archive / North Carolina / Mesoscale Discussions in 2021
Mesoscale Discussion 1416
The Storm Prediction Center issued this mesoscale discussion at Aug 1, 2021, 2:53 PM EDT for 37 counties in North Carolina; 7 counties in South Carolina. It was in force for 97 min.
The area
The outline as issued.
The facts
- Issued
- Aug 1, 2021, 2:53 PM EDT (18:53 UTC)
- Expired
- Aug 1, 2021, 4:30 PM EDT
- In force
- 97 min
- Issued by
- the Storm Prediction Center
- Concerning
- Severe thunderstorm watch 408
All 44 counties
Anson County, NC, Beaufort County, NC, Bertie County, NC, Bladen County, NC, Chatham County, NC, Columbus County, NC, Craven County, NC, Cumberland County, NC, Dare 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, Montgomery County, NC, Moore 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, Chesterfield County, SC, Darlington County, SC, Dillon County, SC, Florence County, SC, Kershaw County, SC, Marion County, SC, Marlboro County, SC
The radar
The Raleigh/Durham radar (KRAX), 83 km from the middle of the area, began a volume at 18:52 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, 6.9 hours before the alert went out and 110 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
- 756 J/kg
- Mixed-layer CIN
- -48 J/kg
- Mixed-layer LCL
- 934 m above ground
- 0-6 km bulk shear
- 28 kt
- 0-1 km storm-relative helicity
- 54 m²/s²
- 0-3 km storm-relative helicity
- 99 m²/s²
- Significant tornado parameter
- 0.1
- Supercell composite
- 2.4
The text
As transmitted.
463
ACUS11 KWNS 011853
SWOMCD
SPC MCD 011853
NCZ000-SCZ000-012030-
Mesoscale Discussion 1416
NWS Storm Prediction Center Norman OK
0153 PM CDT Sun Aug 01 2021
Areas affected...Central/Eastern NC...Northeastern SC
Concerning...Severe Thunderstorm Watch 408...
Valid 011853Z - 012030Z
The severe weather threat for Severe Thunderstorm Watch 408
continues.
SUMMARY...Severe threat across much of central/eastern NC and
northeast SC is expected to continue throughout the afternoon.
DISCUSSION...Cluster of thunderstorms ahead of the surface low about
30 miles west of GSB continues to show sporadic updraft
intensification as a generally multicell-in-cluster mode dominates.
Winds north of Pamlico Sound have mostly veered southwesterly, but
south of the Sound winds are still southeasterly. These
southeasterly winds may contribute to an increase in low-level
vertical shear, resulting in slightly greater severe risk across
this region as both low-level convergence and storm-relatively
helicity increase.
Another round of showers and thunderstorms has also developed across
central NC/north-central SC. The downstream area across southern NC
and adjacent northeast SC remains very moist and moderately
unstable, suggesting the potential for damaging downbursts will
persist throughout the afternoon.
..Mosier.. 08/01/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...AKQ...MHX...RAH...ILM...CAE...GSP...
LAT...LON 34267744 33857938 34338065 35597991 36027777 36127625
35617562 34267744SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 1, 6:29 AM EDT | Mesoscale Discussion | SPC | Alamance, Caswell, Chatham, Davidson, Durham, Franklin and 9 more | 91 min |
| Aug 1, 10:54 AM EDT | Mesoscale Discussion | SPC | Bertie, Camden, Chowan, Currituck, Gates, Hertford and 4 more | 96 min |
| Aug 1, 11:51 AM EDT | Mesoscale Discussion | SPC | Beaufort, Bertie, Chowan, Cumberland, Duplin, Edgecombe and 14 more | 114 min |
| Aug 1, 12:37 PM EDT | Severe Thunderstorm Watch | SPC | Beaufort, Bladen, Brunswick, Carteret, Chatham, Columbus and 31 more | 7 hr |
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.