Alert archive / North Carolina / Mesoscale Discussions in 2021

Mesoscale Discussion 583

May 10, 202111 counties in North Carolina

The Storm Prediction Center issued this mesoscale discussion at May 10, 2021, 6:07 PM EDT for 11 counties in North Carolina. It was in force for 53 min.

The area

The outline as issued.

The facts

Issued
May 10, 2021, 6:07 PM EDT (22:07 UTC)
Expired
May 10, 2021, 7:00 PM EDT
In force
53 min
Issued by
the Storm Prediction Center
Concerning
Severe thunderstorm watch 163

Counties Edgecombe County, NC, Franklin County, NC, Greene County, NC, Johnston County, NC, Lenoir County, NC, Martin County, NC, Nash County, NC, Pitt County, NC, Wake County, NC, Wayne County, NC, Wilson County, NC

The radar

The Raleigh/Durham radar (KRAX), 35 km from the middle of the area, began a volume at 22:10 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 149 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-pSkew-T log-p diagram, Newport, NC at 12:00Z on 2021-05-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1414 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Newport, NC at 12:00Z on 2021-05-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 235 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
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
1414 J/kg
Mixed-layer CIN
-27 J/kg
Mixed-layer LCL
607 m above ground
0-6 km bulk shear
45 kt
0-1 km storm-relative helicity
235 m²/s²
0-3 km storm-relative helicity
235 m²/s²
Significant tornado parameter
1.6
Supercell composite
7.9

Open this sounding in Storm Lab

The text

As transmitted.

981 
ACUS11 KWNS 102207
SWOMCD
SPC MCD 102207 
NCZ000-102300-

Mesoscale Discussion 0583
NWS Storm Prediction Center Norman OK
0507 PM CDT Mon May 10 2021

Areas affected...Portions of central and east-central North Carolina

Concerning...Severe Thunderstorm Watch 163...

Valid 102207Z - 102300Z

The severe weather threat for Severe Thunderstorm Watch 163
continues.

SUMMARY...Isolated large hail and damaging wind gusts are possible
for the next few hours across portions of central and east-central
North Carolina.

DISCUSSION...Storms along and near a cold front moving through North
Carolina have produced occasional large hail and damaging wind gusts
thus far. Expect this isolated threat to continue for a few more
hours before instability decreases further after sunset. A dearth of
moisture has limited MLCAPE to around 500 to 750 J/kg in the region,
but strong shear has allowed for enough storm organization for some
stronger convection and a few supercell structures. The primary
limiting factor to a greater severe threat is the rapid southward
movement of the cold front which has undercut many updrafts thus
far. This continued southward movement of the cold front and a
cooling boundary layer after sunset should limit the severe weather
threat by late evening with a few damaging wind gusts and isolated
large hail possible in the next few hours.

..Bentley.. 05/10/2021

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

ATTN...WFO...AKQ...MHX...RAH...

LAT...LON   35787927 36117831 36167753 35927702 35637700 35167748
            35047800 35507906 35787927

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 10, 12:51 PM EDTMesoscale DiscussionSPCAlamance, Beaufort, Bertie, Bladen, Camden, Carteret and 46 more114 min
May 10, 3:57 PM EDTSevere Thunderstorm WatchSPCAlamance, Beaufort, Chatham, Craven, Cumberland, Davidson and 25 more6 hr

Nearby

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.