Alert archive / North Carolina / Mesoscale Discussions in 2021
Mesoscale Discussion 1354
The Storm Prediction Center issued this mesoscale discussion at Jul 26, 2021, 5:43 PM EDT for 9 counties in North Carolina; City of Chesapeake, City of Franklin, City of Suffolk, Virginia. It was in force for 92 min.
The area
The outline as issued.
The facts
- Issued
- Jul 26, 2021, 5:43 PM EDT (21:43 UTC)
- Expired
- Jul 26, 2021, 7:15 PM EDT
- In force
- 92 min
- Issued by
- the Storm Prediction Center
- Concerning
- Severe potential...watch unlikely
- Chance of a watch
- 20%
Counties Camden County, NC, Chowan County, NC, Currituck County, NC, Gates County, NC, Hertford County, NC, Pasquotank County, NC, Perquimans County, NC, Tyrrell County, NC, Washington County, NC, City of Chesapeake, VA, City of Franklin, VA, City of Suffolk, VA
The radar
The Norfolk radar (KAKQ), 100 km from the middle of the area, began a volume at 21:45 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, 9.7 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
- 1376 J/kg
- Mixed-layer CIN
- -3 J/kg
- Mixed-layer LCL
- 595 m above ground
- 0-6 km bulk shear
- 14 kt
- 0-1 km storm-relative helicity
- 30 m²/s²
- 0-3 km storm-relative helicity
- 46 m²/s²
- Significant tornado parameter
- 0.1
- Supercell composite
- 0.9
The text
As transmitted.
822
ACUS11 KWNS 262143
SWOMCD
SPC MCD 262143
NCZ000-VAZ000-262315-
Mesoscale Discussion 1354
NWS Storm Prediction Center Norman OK
0443 PM CDT Mon Jul 26 2021
Areas affected...Far northeast North Carolina and far southeast
Virginia
Concerning...Severe potential...Watch unlikely
Valid 262143Z - 262315Z
Probability of Watch Issuance...20 percent
SUMMARY...There will be an isolated damaging wind threat across far
southeast Virginia and far northeast North Carolina over the next 1
to 2 hours. No watch is anticipated.
DISCUSSION...The cluster of storms which produced some damaging wind
across eastern Virginia has shown some weakening as it moves
southward toward areas with decreasing effective shear. However, the
airmass ahead of these storms is still quite unstable with MLCAPE
around 2500 J/kg. Therefore, an isolated severe wind threat may
persist as this activity moves southeastward out of watch 392.
However, a more organized threat is not anticipated, and therefore,
no downstream watch is planned.
..Bentley/Grams.. 07/26/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...AKQ...MHX...
LAT...LON 36697700 36757631 36707588 36307565 36137563 35857560
35777578 35767614 35787669 36007691 36237711 36497728
36697700SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 26, 12:58 PM EDT | Mesoscale Discussion | SPC | Alamance, Cabarrus, Caswell, Chatham, Davidson, Davie and 17 more | 2 hr |
| Jul 26, 1:39 PM EDT | Severe Thunderstorm Watch | SPC | Alamance, Caswell, Davidson, Forsyth, Guilford, Orange and 4 more | 6 hr |
| Jul 26, 3:29 PM EDT | Mesoscale Discussion | SPC | Alamance, Caswell, Davidson, Durham, Forsyth, Granville and 10 more | 2 hr |
Nearby
Mesoscale Discussions in North Carolina, 2021Mesoscale Discussions in Virginia, 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.