SPC Jan 7, 2024 0830 UTC Day 3 Severe Thunderstorm Outlook

[NorthGeorgiaWX]

SPC 0830Z Day 3 Outlook

Day 3 Convective Outlook AMEND 1
NWS Storm Prediction Center Norman OK
0120 PM CST Sun Jan 07 2024

Valid 091200Z - 101200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER THE FL
PANHANDLE...SOUTHEAST AL...AND SOUTHWEST GA...

AMENDED FOR INCREASED SEVERE PROBABILITIES OVER THE FL PANHANDLE,
SOUTHEAST AL, AND SOUTHWEST GA.

...SUMMARY...
Strong to severe thunderstorms may impact much of the eastern Gulf
and southern Atlantic Coast states Tuesday, accompanied by a risk
for damaging wind gusts and tornadoes.

...FL Panhandle/Southeast AL/Southern GA Tuesday morning...
General expectation is that a fast-moving, well-organized convective
line will be ongoing at the beginning of the period across the
western FL Panhandle and southeast AL. Robust kinematic fields
suggest that strong gusts are likely within this line. Additionally,
large, looping low-level hodographs indicate there is possibility
for line-embedded QLCS tornadoes as well. With the mid-latitude
cyclone (and associated large-scale ascent) becoming increasingly
displaced to the north, relatively warm mid-level temperatures
downstream across northern FL and southern GA are currently expected
to lead to some decrease in the intensity of the line as it
continues eastward.

...Coastal/Central Carolinas...
As the system becomes negatively tilted, strong low-level moisture
advection is anticipated ahead of the approaching cold front and
associated convective line. This increase in low-level moisture will
likely be accompanied by widespread cloud cover and showers,
limiting diurnal heating. As a result, despite increasing low-level
moisture, the combination of limited heating and relatively warm
mid-level temperatures could stunt overall buoyancy and updraft
strength. 

.PREV DISCUSSION... /ISSUED 0215 AM CST Sun Jan 07 2024/

...Synopsis...
Models indicate that mid/upper ridging will amplify once again
within the prevailing split flow across the eastern mid-latitude
Pacific.  As the occurs, mid-level troughing is forecast to begin to
dig across Pacific Northwest, and a strong downstream trough,
initially approaching the Mississippi Valley, likely will remain
progressive. 

Strong cyclogenesis appears likely to proceed from the Mississippi
Valley through much of the eastern U.S., with the center of the
primary surface cyclone still generally forecast to track from the
Ozark Plateau/Mid South vicinity through the lower Great Lakes
region by late Tuesday night.  Models indicate that the mid/upper
trough axis will take on a negative tilt while pivoting northeast of
the Mississippi Valley, with strongest difluence aloft overspreading
much of the Southeast.  Further intensification of
lower/mid-tropospheric wind fields may include 50-80+ kt southerly
to southwesterly flow in the 850-700 mb layer overspreading much of
the eastern Gulf/southern Atlantic Coast region during the day
Tuesday, accompanied by a moistening warm sector.

...Southeast...
Associated with the strong synoptic forcing for ascent, a strong to
severe squall line, perhaps closely preceded by discrete supercell
development, may be ongoing ahead of an eastward surging cold front
across parts of central/southern Alabama into the northeastern Gulf
of Mexico at 12Z Tuesday.  While the forcing for ascent likely will 
remain sufficient to maintain this convective development across
much of the eastern Gulf and southern Atlantic Coast region by
Tuesday evening, the extent to which thermodynamic profiles become
supportive remains unclear.

While inflow off the Atlantic into the Carolinas may contribute to
pre-frontal low-level moistening even if the Gulf moist inflow
becomes cut off, model forecast soundings suggest that relatively
warm layers aloft with weak lapse rates will generally inhibit
appreciable boundary-layer destabilization.  It is possible that
this could contribute to weakening convective trends at some point
across Georgia and Florida, before convection potentially
intensifies once again across the Carolinas, before advancing
offshore.

This uncertainty, among others, precludes an outlook of higher
severe probabilities at this time.  However, given the synoptic
forcing, the strength of the deep-layer wind fields, and the large
clockwise-curved hodographs evident in forecast soundings, the
environment seems likely to become at least conditionally supportive
of convection capable of producing a few strong tornadoes and/or
widespread damaging wind gusts.

..Mosier.. 01/07/2024

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