Alert archive / North Carolina / Mesoscale Discussions in 2021

Mesoscale Discussion 912

June 10, 20216 counties in North Carolina; Dillon County, Horry County, Marion County, South Carolina

The Storm Prediction Center issued this mesoscale discussion at Jun 10, 2021, 8:11 PM EDT for 6 counties in North Carolina; Dillon County, Horry County, Marion County, South Carolina. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued: Jun 10, 2021, 8:11 PM EDT (00:11 UTC)
Expired: Jun 10, 2021, 10:15 PM EDT
In force: 2 hr
Issued by: the Storm Prediction Center
Concerning: Severe potential...watch unlikely
Chance of a watch: 5%

Counties Bladen County, NC, Brunswick County, NC, Columbus County, NC, New Hanover County, NC, Pender County, NC, Robeson County, NC, Dillon County, SC, Horry County, SC, Marion County, SC

The radar

The Wilmington radar (KLTX), 39 km from the middle of the area, began a volume at 00:13 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

Charleston AFB, SC (KCHS), launched 00:00Z, 0.2 hours before the alert went out and 184 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.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 1267 J/kg
Mixed-layer CIN: -50 J/kg
Mixed-layer LCL: 1056 m above ground
0-6 km bulk shear: 5 kt
0-1 km storm-relative helicity: 49 m²/s²
0-3 km storm-relative helicity: 69 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

045 
ACUS11 KWNS 110011
SWOMCD
SPC MCD 110011 
NCZ000-SCZ000-110215-

Mesoscale Discussion 0912
NWS Storm Prediction Center Norman OK
0711 PM CDT Thu Jun 10 2021

Areas affected...Northeast South Carolina and southeast North
Carolina

Concerning...Severe potential...Watch unlikely 

Valid 110011Z - 110215Z

Probability of Watch Issuance...5 percent

SUMMARY...A linear cluster of storms with an organized outflow may
produce sporadic damaging winds as it moves towards the coast over
the next hour. A watch is not expected.

DISCUSSION...A linear cluster of storms has gradually strengthened
over the past hour over northern South Carolina within a moist and
weakly capped environment. While other convective cells and clusters
to the north have weakened due to convective overturning/outflow
from prior activity, this cluster has largely remained within a
favorable air mass. KLTX velocity data suggests an organized outflow
has developed, which will likely continue for the next hour or so
thanks to line-normal (though weak) low to mid-level flow (per the
KLTX VWP). One mitigating factor is increasing inhibition on the
northern side of a residual outflow boundary just ahead of the
cluster, though forcing along the outflow may allow parcels to reach
their LFCs and maintain the cluster as it moves towards the coast.
Overall, a few damaging wind gusts are possible, but the severe
threat is expected to remain too localized to warrant a watch.

..Moore/Dial.. 06/11/2021

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...RAH...ILM...

LAT...LON   34807931 34857884 34627805 34287746 33727776 33727832
            33507875 33567900 33857944 34237955 34447952 34807931

Nearby

Mesoscale Discussions in North Carolina, 2021 Mesoscale Discussions in South Carolina, 2021 Every 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.