Mesoscale Discussion 9

Issued

Jan 1, 2021, 4:27 PM EST (21:27 UTC)

Expired

Jan 1, 2021, 6:30 PM EST

In force

2 hr

Issued by

the Storm Prediction Center

Concerning

Tornado watch 1

The Robins AFB radar (KJGX), 107 km from the middle of the area, began a volume at 21:25 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.

814 
ACUS11 KWNS 012127
SWOMCD
SPC MCD 012127 
SCZ000-GAZ000-012330-

Mesoscale Discussion 0009
NWS Storm Prediction Center Norman OK
0327 PM CST Fri Jan 01 2021

Areas affected...Parts of the east central Georgia into central
South Carolina Piedmont

Concerning...Tornado Watch 1...

Valid 012127Z - 012330Z

The severe weather threat for Tornado Watch 1 continues.

SUMMARY...Supercell structures accompanied by the risk for tornadoes
may continue to develop through the 5-7 PM EST time frame,
particularly with storms spreading into and across the Augusta GA
vicinity, toward Columbia SC.

DISCUSSION...A broken (northeast-southwest oriented) line of
convection continues to progress eastward across Georgia, roughly
aligned with a remnant 30-40+ kt south-southwesterly 850 mb jet
axis.  South of the northeastward advancing warm front, now roughly
across and east of Athens into areas of South Carolina to the
southwest of Columbia, at least weak low-level rotation has been
evident along the length of the line.  However, most pronounced
mesocyclogenesis, accompanied by the risk for tornadoes, has been
within a corridor to the south/within the immediate wake of the warm
front, perhaps aided by residual enhanced near-surface shear in the
presence of a weakly destabilizing boundary layer.

Strongest convection is now developing east-northeastward to the
west and north of Augusta GA.  This appears likely to continue to
spread into the South Carolina Piedmont through 5-7 PM.  Given the
cool, stable nature of the boundary layer to the north of the sharp
frontal zone, as convection crosses the front it should tend to
weaken.  However, there appears a corridor across and east of the
Augusta area where the environment appears to remain potentially
more conducive to organizing and intensifying supercell structures
capable of producing tornadoes. This could approach the Columbia
area toward 00-01Z.

..Kerr.. 01/01/2021

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

ATTN...WFO...CHS...CAE...GSP...FFC...

LAT...LON   32428335 33748288 34048207 33938091 33448108 32638223
            32518296 32428335

Mesoscale Discussions in Georgia, 2021Mesoscale Discussions in South Carolina, 2021Every mesoscale discussion in 2021

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.