486
FXUS62 KFFC 191752
AFDFFC

Area Forecast Discussion
National Weather Service Peachtree City GA
152 PM EDT Fri Jul 19 2024



...New 18Z Aviation Discussion...

.SHORT TERM...
(Today through Saturday)
Issued at 333 AM EDT Fri Jul 19 2024

Thanks to a broad 500 mb trough over the eastern CONUS, and a
stationary boundary that has stalled over north Georgia, the short
term forecast is going to sound a bit like a broken record with
similar conditions on the horizon as to what we have seen over the
last several days. As the surface boundary remains in place and a
shortwave approaches from the west, southwest winds will advect
abundant moisture from the Gulf of Mexico into the atmospheric
column. As disturbances within the upper level flow pass overhead,
multiple waves of shower and thunderstorm activity are expected to
occur today, into the overnight hours, and again on Saturday. The
bulk of the thunderstorm activity is expected to be driven
diurnally, and is most likely to occur primarily during the
afternoon and early evening hours. However, a few rumbles of thunder
outside of this timeframe will certainly be possible. With SBCAPE
peaking between 1000-2000 J/kg during the afternoon and bulk shear
~25kt, a few storms could become strong, but the probability for
widespread severe weather remains low. With PWATs north of 2.0", a
few strong storms could produce instances of locally heavy rainfall.
While this forecast isn`t particularly conducive to spending time
outdoors this weekend, at least cooler daytime temperatures will
prevail, with locations north of a line from Columbus to Eatonton to
Washington in the 80s with areas south in the low 90s.

KAB

&&

.LONG TERM...
(Saturday night through Thursday)
Issued at 333 AM EDT Fri Jul 19 2024

Key Messages:

 -  Numerous afternoon and evening thunderstorms will continue in
the region over the next 7 days.

 - Slightly below average high temperatures (by 2-5 degrees) and
above average rainfall are favored in northern and central Georgia
through next Thursday.

A Rinse & Repeat Forecast Next Week:

As we move through the upcoming workweek the ensemble guidance (GEFS
and EPS) favors a stagnant pattern with upper level troughing over
the Central Plains/Midwest and an upper level ridge over the Western
Atlantic. Prevailing southwesterly flow between these two features
should keep subtropical moisture flowing into Georgia from the Gulf.
Mean forecast PW values from the GEFS and EPS remain at or above the
90th percentile (~1.8 inches) through at least next Thursday. The
elevated moisture levels should be accompanied by a lack of
significant mid/upper level subsidence (thanks to the positioning of
the upper level ridge and trough) and this should promote
convection. This should be especially true during the afternoon and
evening hours each day when diurnal heating is maximized. Run to run
trends in the GEFS and EPS guidance have consistently shown 7 day
precipitation anomalies (ending next Thursday) of 1 to 3 inches over
northern and central Georgia. As such forecaster confidence in above
average precipitation through next Thursday is moderate (especially
over northern Georgia). Though thunderstorms are anticipated each
day, severe weather remains unlikely through next Thursday due to a
lack of appreciable wind shear. A few strong storms could still
occur each day, with precipitation loading supporting isolated
downburst wind gusts near 40 mph.

Lower heights induced by the trough to our west and cloud cover from
diurnally driven convection should keep our high temperatures at or
below seasonal averages during the upcoming work week. Our running
forecast keeps afternoon highs in the upper 80s for most of northern
Georgia with low 90s in central Georgia. If these readings
materialize, they would be 2 to 5 degrees below seasonal averages
for the second half of July (the largest deviation in northern
Georgia).

Albright

&&

.AVIATION...
(18Z TAFS)
Issued at 143 PM EDT Fri Jul 19 2024

Thunderstorms with a bit more organization have begun over north
GA but the cloud cover that lingered over the remainder of the
area will hold off thunderstorms for ATL until 19z. Still
expecting the IFR CIGs to enter the area ~8-9z and linger through
the morning before lifting to MVFR ~16-17z.

//ATL Confidence...18Z Update...
Medium on all elements.

Hernandez

&&

.PRELIMINARY POINT TEMPS/POPS...
Athens          70  87  70  89 /  50  60  70  80
Atlanta         70  85  71  86 /  60  60  70  90
Blairsville     65  80  65  80 /  50  60  70  90
Cartersville    69  85  69  85 /  50  60  70  90
Columbus        72  90  72  91 /  50  60  50  90
Gainesville     70  84  71  85 /  50  60  70  80
Macon           70  91  71  91 /  40  60  50  80
Rome            70  85  70  85 /  40  60  70  90
Peachtree City  69  87  70  87 /  50  60  70  90
Vidalia         73  93  74  94 /  40  50  40  80

&&

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

$$

SHORT TERM...KAB
LONG TERM....Albright
AVIATION...Hernandez