Alert archive / North Carolina / Mesoscale Discussions in 2021
Mesoscale Discussion 839
The Storm Prediction Center issued this mesoscale discussion at Jun 2, 2021, 5:47 PM EDT for 8 counties in North Carolina. It was in force for 88 min.
The area
The outline as issued.
The facts
- Issued
- Jun 2, 2021, 5:47 PM EDT (21:47 UTC)
- Expired
- Jun 2, 2021, 7:15 PM EDT
- In force
- 88 min
- Issued by
- the Storm Prediction Center
- Concerning
- Severe potential...watch unlikely
- Chance of a watch
- 5%
Counties Bladen County, NC, Columbus County, NC, Craven County, NC, Duplin County, NC, Jones County, NC, Onslow County, NC, Pender County, NC, Sampson County, NC
The radar
The Wilmington radar (KLTX), 75 km from the middle of the area, began a volume at 21:51 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, 9.8 hours before the alert went out and 115 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
- 614 J/kg
- Mixed-layer CIN
- -6 J/kg
- Mixed-layer LCL
- 609 m above ground
- 0-6 km bulk shear
- 22 kt
- 0-1 km storm-relative helicity
- 58 m²/s²
- 0-3 km storm-relative helicity
- 65 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.7
The text
As transmitted.
669
ACUS11 KWNS 022147
SWOMCD
SPC MCD 022147
NCZ000-SCZ000-022315-
Mesoscale Discussion 0839
NWS Storm Prediction Center Norman OK
0447 PM CDT Wed Jun 02 2021
Areas affected...parts of southern North Carolina
Concerning...Severe potential...Watch unlikely
Valid 022147Z - 022315Z
Probability of Watch Issuance...5 percent
SUMMARY...A brief tornado remains possible with any of the stronger
storms with more persistent low-level rotation. The tornado threat
is expected to be too sparse and localized to warrant a WW issuance.
DISCUSSION...Semi-discrete storms, exhibiting occasional transient
supercell structure, have been showing signs of stronger, more
persistent low-level rotation over the past hour or so, as shown by
MRMS mosaic radar imagery. A tornado was reported with a transient
supercell in Duplin County, and KLTX high-resolution radar data is
also showing weak low-level mesocyclone development with storms
entering Bladen and Columbus counties. While recent KMHX and KLTX
VWPs suggest that low-level shear is weak overall, these
semi-discrete storms are traversing a diffuse baroclinic zone, where
locally enhanced effective SRH and 1000 J/kg MLCAPE (with 150 J/kg
0-3 km CAPE) is supporting updraft organization and occasional
low-level rotation. As such, a brief tornado or two remains possible
for a few more hours, before convective overturning or
boundary-layer cooling serve to diminish any remaining severe
threat. The very isolated, brief nature of the tornado threat
precludes a WW issuance.
..Squitieri/Thompson.. 06/02/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...MHX...RAH...ILM...
LAT...LON 34357913 34737895 34927875 35167807 35257745 35187701
34857689 34597712 34347759 34177801 34077852 34037900
34357913Nearby
Mesoscale Discussions in North 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.