612
FXUS62 KFFC 071803
AFDFFC

Area Forecast Discussion
National Weather Service Peachtree City GA
203 PM EDT Tue May 7 2024



...New 18Z Aviation Discussion...

.SHORT TERM...
(Today through Wednesday)
Issued at 336 AM EDT Tue May 7 2024

500mb analysis shows nearly zonal flow across the CWA this morning.
Shortwave ridging is expected to build today, but quickly return to
a more zonal pattern on Wednesday. At the surface, high pressure
will remain in place. A weak surface boundary will remain well north
of the area.

Models continue to struggle with the pattern in place, with most of
the forcing within the mid or very upper levels of the atmosphere
for much of the SE US. With the shortwave ridging in place for much
of today, convection should be fairly limited. Models have been
consistent with isolated to scattered convection developing very
late in the afternoon/early evening across portions of north central
AL and moving into north GA. This activity seems to be related from
a possible outflow boundary in association with convection that is
currently well to the west of here. The solution seems reasonable,
but his highly dependent upon the evolution of what goes on out
west. There will be enough instability to work with and lapse rates
will be fairly steep, if the convection/outflow can survive and
make it this far to the east.

Wednesday seems to be the more active of days for the CWA. The flow
in the mid levels will go back to a more zonal pattern. In addition,
there will be coupled jet structure aloft to potentially provide
some widespread lift in the very upper levels. This activity is also
dependent upon organized convection that develops out west and moves
east. There is an axis of good instability and steep lapse rates,
especially across northern portions of the state. Not confident
enough to go likely pops, but high chance should suffice for now.

Good instability and steep lapse rates will persist this evening and
through Wednesday. There is some potential for isolated severe
storms, with the primary hazards being damaging winds and large
hail.

NListemaa

&&

.LONG TERM...
(Wednesday night through Monday)
Issued at 336 AM EDT Tue May 7 2024

An ongoing potentially active weather period will characterize the
start of the long term forecast Wednesday night into Thursday
morning. Convection, some likely severe, will be in progress
somewhere across the Tennessee Valley in the form of one or multiple
MCSs Wednesday night. This activity should gradually progress east-
southeastward in the well in advance of the surface cold front
through Thursday morning. Models tend to struggle in this type of
environment regarding the placement/timing of convection, so a
significant degree of uncertainty does remain. With that said, in
general PoPs will be on the increase across north Georgia from
late Wednesday night into Thursday morning with some associated
severe potential also increasing through this time. Given 0-6 km
bulk shear values of 40-50+ knots, damaging wind gusts would be
the primary concern with any convective complex that could enter
north Georgia with large hail and perhaps an embedded brief spin-
up tornado threat as well. To highlight this potential, SPC has
maintained a Slight Risk for far north Georgia and a Marginal Risk
down to roughly I-20 for the late Day 2 period from late
Wednesday night into early Thursday morning.

As we head later in the day on Thursday, the surface cold front will
begin to approach and push into the area. The front will get its
most sustained push into the area by Thursday afternoon as the upper
trough deepens across the Great Lakes. Additional convection will
likely develop in advance of the front by Thursday afternoon, though
coverage and degree of additional severe potential will to some
degree depend on the evolution of morning convection and any
lingering boundaries/cold pool. If forecast instability is
realized, a resurgent severe threat would be likely by Thursday
afternoon/evening. Amid still-favorable deep layer shear and 6-7
C/km lapse rates, damaging wind gusts and large hail could be
expected. A Day 3 Slight Risk thus envelopes most of the area
generally along and south of the I-85 corridor to account for this
risk. Lastly, models continue to highlight a potential eastward-
moving MCS that would track along/north of the Gulf coast late
Thursday into Thursday night that could possibly skirt southern
portions of the area and perhaps pose an additional severe risk.

Thereafter, some PoPs will linger across Middle Georgia on Friday
before the front finally clears the area Friday night. Northwest
flow aloft will persist through the weekend into early next week
while high pressure returns at the surface. A couple of shortwaves
could swing across the area within the northwest flow aloft over the
weekend, but at this point kept PoPs 10 percent or less. Much more
comfortable below normal temperatures and low humidity will persist
into early next week.

RW

&&

.AVIATION...
(18Z TAFS)
Issued at 159 PM EDT Tue May 7 2024

VFR to start the TAF period. VFR Cloud cover continues to lift
and scatter across most sites this afternoon and will continue
into the evening, though some SCT040-060 will remain east and west
of ATL. Cigs expected to lower to low MVFR/high IFR tonight
across CSG and metro TAF sites, including ATL during morning
hours, approx 10Z-14Z. Increasing moisture ahead of next system
means BKN cloud cover will likely stick around through afternoon
tomorrow. Some isolated storms will be possible by afternoon hours
as well. Winds will be SW from 5-10 kts through TAF period.


//ATL Confidence...18Z Update...

Medium-high morning cigs, high all others.

Lusk

&&

.PRELIMINARY POINT TEMPS/POPS...
Athens          68  89  69  85 /  10  30  40  80
Atlanta         70  88  69  85 /  20  30  50  80
Blairsville     65  81  63  77 /  40  60  80  90
Cartersville    68  87  66  85 /  40  40  60  90
Columbus        70  91  71  89 /  10  20  20  70
Gainesville     69  86  69  83 /  30  50  60  90
Macon           70  91  71  88 /   0  10  10  70
Rome            68  87  67  85 /  40  50  70  90
Peachtree City  68  89  69  86 /  10  30  30  80
Vidalia         70  92  71  92 /   0  10  10  50

&&

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

$$

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