SPC Jan 11, 2024 2000 UTC Day 1 Convective Outlook

[NorthGeorgiaWX]

SPC 2000Z Day 1 Outlook

Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
0139 PM CST Thu Jan 11 2024

Valid 112000Z - 121200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS LATE TONIGHT
AND EARLY FRIDAY MORNING ACROSS PORTIONS OF THE ARKLATEX REGION...

...SUMMARY...
Tornadoes, damaging wind gusts, and large hail are possible tonight
over the Arklatex region, and nearby parts of southeastern Oklahoma,
east Texas, Arkansas, and western/northern Louisiana.

...20Z Update...

...East TX and Arklatex into the Ozark Plateau tonight...
Low-level moisture continues to advect northward across East TX,
with low 60s dewpoints now reaching as far north as Rusk County TX.
That matches fairly well with the last RAP guidance, which then
brings 60s dewpoints into the TXK vicinity around 03Z.

Elevated thunderstorm development is still anticipated tonight
(00Z-03Z) from the Arklatex into nearby central AR within the strong
warm-air advection preceding the shortwave current moving through
the Four Corners region. Strong deep-layer vertical shear should
support rotating updrafts and some potential for large hail. As
mentioned in the previous outlook, upper 50s to low 60s dewpoints
might be sufficient for surface-based supercells capable of all
hazards, including tornadoes.

Additional development is still expected to the west of this
earlier, predominantly elevated activity as the strong mid-level jet
progresses over the warm sector and a cold front surges westward.
Storms are then expected to form along/ahead of this cold front from
eastern OK int northeast TX and track rapidly east-northeastward
across the ENH area. Primary storm mode will likely be bowing line
segments, with an attendant threat for strong to significant gusts
and tornadoes, particularly across east-central/southeast AR early
Friday morning.

Some storm development is also possible close to the primary surface
low as well, and severe-wind probabilities were extended northward
to account for this potential.

..Mosier.. 01/11/2024

.PREV DISCUSSION... /ISSUED 1030 AM CST Thu Jan 11 2024/

Morning water vapor imagery shows a progressive upper trough digging
southeastward toward the Four Corners region.  This trough and
associated intense mid/upper level jet will move into the southern
Plains tonight, aiding in rapid cyclogenesis over OK/TX. 
Strengthening southerly low-level winds in the warm sector will
transport Gulf moisture northward and result in a corridor of severe
thunderstorm activity late tonight.

Present indications are that storms will first form in the warm
advection regime across parts of AR after dark.  These initial
storms will be in an environment of steep mid-level lapse rates and
strong deep-layer shear, favorable for large hail.  Supercell
structures will be favored, and dewpoints in the upper 50s might be
sufficient for at least a modest risk of a tornado or two.

The more robust severe threat is likely to evolve after midnight as
the mid-level jet max surges eastward across east TX and atop the
warm sector.  Storms are expected to form along/ahead of the cold
front over northeast TX and track rapidly east-northeastward across
the ENH area.  The overall synoptic setup for this event would be
very impressive and favorable for severe thunderstorms, but
low-level moisture is somewhat lacking.  Nevertheless, fast-moving
supercells and bowing structures are possible early Friday morning
as storms trek across parts of AR and northern LA.  Widespread
damaging winds and strong tornadoes are possible - especially if
low-level moisture is just slightly greater than currently forecast.

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