545
FXUS62 KFFC 081049
AFDFFC

Area Forecast Discussion
National Weather Service Peachtree City GA
649 AM EDT Wed May 8 2024



...New 12Z Aviation Discussion...

.SHORT TERM...
(Today through Thursday)
Issued at 343 AM EDT Wed May 8 2024

Challenging forecast for the entire short term period.

Weak high pressure remains in place across the CWA this morning. A
nearly stationary frontal boundary stretches from the central Great
Lakes back through central Texas. A warm front is situated across
the northern Mid Atlantic States. All of the SE US and Gulf States
remain within the warm sector with an atmosphere very conducive for
convection through the short term period. However, timing/coverage
is HIGHLY dependent on upstream convection/potential MCS
development. Earlier today should be fairly quiet with thunderstorm
potential increasing this evening and lasting well into Thursday.

500mb analysis shows shortwave ridging beginning to move offshore.
One mid level low is across the upper Plains states and the second
is across the central Great Lakes. The Great Lakes low is expected
to move eastward across New England and the upper Plains slow will
move east-southeast through the period. The main energy with these
two low pressure systems should remain well to the north of the CWA.
However, models are progging a strong shortwave to drop southeast
overnight Wednesday into early Thursday. Thickness values during
this time definitely indicate the potential for a MCS moving across
portions of the CWA.

Since most of the convection during the short term period is
dependent upon upstream activity and any development of an MCS, the
forecast will be very challenging. The models have been fairly
consistent from run to run showing an MCS dropping southeast from
the TN Valley late Wednesday/early Thursday morning. However, not
quite sure the hi-res models have a great handle on the evolution of
this system. The HRRR has a couple of  distinct waves of convection,
with one them the MCS in question. The waves of convection are
fairly close together and an earlier system could definitely impact
the evolution of a later system. The first system could
move SE across northern  portions of the state Wednesday evening
and into the overnight hours. A secondary wave of convection is
progged to approach northern portions of the state early
Thursday morning, near 12Z...potentially the main MCS. This system
moves southeast across much of the CWA during the day. The evolution
of this system is VERY dependent upon any earlier convection.

If the evening/overnight wave holds together and does impact
portions of north/northeast GA, this area could get worked over
fairly well before the main MCS moves through. However, if the wave
doesn`t hold together, northeast portions of the CWA will have the
same potential for severe weather the remainder of the CWA when the
main MCS is forecast to move through. Do think the potential
for hazardous weather will be greater with the main MCS
that begins to move through early Thursday morning and continues
southward through the day.

All of the parameters will be there for severe thunderstorms with
any waves/MCS that impact the CWA overnight and early Thursday.
There will be plenty of moisture, forcing, shear and instability.
Mid level lapse rates are impressively steep. The primary hazards
for severe thunderstorms haven`t changed from previous days, but
timing will be somewhat difficult to nail down until these systems
actually develop and are able to sustain themselves. Generally,
think the best chances for more widespread storms/severe will be
with the main MCS push. Any activity that develops ahead of the main
MCS will also have the potential to become severe, but maybe not
have the potential to be as widespread. Damaging wind gusts and
large hail will be the primary hazards. There will also be potential
for tornadoes. Locally heavy rainfall is a given.

NListemaa

&&

.LONG TERM...
(Thursday night through Tuesday)
Issued at 343 AM EDT Wed May 8 2024

A cold front will be situated across north Georgia at the start of
the period Thursday night. There may be some ongoing convection
within the area during this time, dependent on how development
trends evolve Thursday afternoon. The focus for later Thursday night
into Friday morning will then turn to the potential for an MCS that
could approach from the west. A shortwave will initiate convection
across east Texas into Louisiana which may congeal into a convective
complex and race eastward Thursday evening through early Friday
morning as supported by much model guidance. Still, uncertainty
remains regarding this scenario as well as the track of said
convective complex if it occurs; however, SBCAPE and bulk shear
parameters would be supportive of a damaging wind threat if this
scenario manifests. The areas most likely to experience impacts
in this case would likely be our Middle Georgia counties and points
southward to the Gulf Coast.

The cold front will make further southward progress on Friday,
shunting lingering PoPs largely to southern portions of the CWA by
the afternoon. Some potential for strong to isolated severe may
remain Friday afternoon in southern zones, though this will
depend to some degree on how any morning MCS impacts evolve. By
Friday evening, the front should finally clear the area and put an
end to the rainfall. In the wake of the front, northwest flow
aloft will persist through the weekend while high pressure builds
in at the surface. A noticeably drier and cooler airmass will
bring temperatures slightly below to near normal through the
weekend.

Drier conditions may be relatively short-lived, however, as high
pressure departs eastward by Monday and southerly low-level flow
returns. An approaching shortwave will begin to increase PoPs to our
west on Monday, and trends may support PoPs higher than currently
forecast by Monday in future forecast cycles. An unsettled pattern
then looks likely to continue thereafter.

RW

&&

.AVIATION...
(12Z TAFS)
Issued at 606 AM EDT Wed May 8 2024

BKN MVFR likely through mid morning. There is some potential for a
brief period of BKN IFR but will keep that confined to the tempo
group. Complex of thunderstorms will likely approach northern
portions of GA close to 12Z THU. MVFR cigs possible again
overnight ahead of the complex of storms. Winds will remain on the
west side.

//ATL Confidence...12Z Update...
Med confidence thunderstorm timing for tomorrow. High confidence
remaining elements.

NListemaa

&&

.PRELIMINARY POINT TEMPS/POPS...
Athens          69  81  64  81 /  40  60  30  30
Atlanta         70  80  66  78 /  40  70  40  30
Blairsville     64  77  57  71 /  70  70  30  20
Cartersville    67  82  60  78 /  60  70  40  20
Columbus        73  85  68  84 /  20  70  50  50
Gainesville     69  80  65  78 /  50  70  30  30
Macon           71  85  66  83 /  20  70  40  50
Rome            68  83  62  78 /  80  80  30  20
Peachtree City  70  81  63  81 /  30  70  50  30
Vidalia         72  90  70  84 /  20  60  50  70

&&

.FFC WATCHES/WARNINGS/ADVISORIES...
None.
&&

$$

SHORT TERM...NListemaa
LONG TERM....RW
AVIATION...NListemaa