-- Discussion containing changed information from previous version are highlighted. --
093
FXUS62 KFFC 211729
AFDFFC

Area Forecast Discussion
National Weather Service Peachtree City GA
129 PM EDT Tue May 21 2024



...New 18Z Aviation Discussion...

.SHORT TERM...
(Today through Wednesday)
Issued at 410 AM EDT Tue May 21 2024

High pressure aloft and at the surface through the short term period
will produce warm and dry conditions throughout the short term
period. The one exception to this will be across northeast Georgia
this afternoon and evening where isolated showers and thunderstorms
will be possible as a weak disturbance to the north passes. With
favorable prevailing surface winds out of the southeast providing a
modest enhancement of daytime upslope winds, SBCAPE between 500-
1000+ J/kg, and some moisture remaining in the lower levels of the
atmosphere, convection in mountainous terrain will be possible
today. Max daily temperatures will climb into the low to mid 80s
today with temperatures reaching the mid to upper 80s tomorrow where
areas in elevated terrain will remain in the 70s. Overnight lows
will range from the upper 50s to mid 60s.

KAL

&&

.LONG TERM...
(Wednesday night through Monday)
Issued at 410 AM EDT Tue May 21 2024

The long term period will begin Wednesday night with upper level
ridging over the East Coast and continuing out towards the Atlantic.
Meanwhile, an occluded low pressure system will be in centered in
southeast Canada and drifting slowly to the north. Between these two
features, southwesterly upper flow will set up over much of the
eastern CONUS, including north Georgia, leading to increasing
atmospheric moisture. A cold front extending from the low will have
moved into the Tennessee Valley region as the period begins, at
which point it will gradually sink southward towards north Georgia
over the course of the day. After the morning starts out with lows
in the mid to upper 60s, isolated to scattered showers and
thunderstorms will begin to advance into far north Georgia by early
Thursday morning as a weak disturbance traverses the upper-level
flow and overruns the frontal boundary. PoPs on Thursday and
Thursday night will mostly be confined to north of the I-20
corridor, with low-end chance PoPs in the far northern tier and and
progressively lower chances to the south. Diurnal instability will
be sufficient for the development of thunderstorms on Thursday,
although severe weather is not likely at this time. Even in spite of
increased cloud cover across far north Georgia near the front, the
warming trend from the short term period will persist, with highs
forecast to be in the upper 80s in north Georgia and low 90s in
central Georgia. These high temperatures will be consistent with
what can be expected for the remainder of the week and into the
weekend, which will run about 5-9 degrees above climatological
normals areawide.

As the low continues weakens and moves away to the northeast, the
upper flow will become more zonally oriented and the frontal
boundary will become more elongated from west to east, with its
southward advance will slowing significantly. By Friday morning, the
frontal boundary is forecast to stall near the Georgia/Tennessee
state line. A more robust shortwave will traverse the westerlies and
from the Lower Mississippi River Valley across the Southeast on
Friday into Friday night. This setup is likely to bring more
numerous showers and thunderstorms to the forecast area on Friday,
especially where the wave overruns the stalled frontal boundary,
providing a focus for additional convection. Uncertainty still
remains in the model guidance with respect to the strength and exact
position of this disturbance, which will influence where the most
widespread precipitation will occur. While the frontal boundary will
begin to dissipate by early Saturday morning, additional
disturbances will continue to traverse the zonal westerlies and move
through the Southeast this weekend. Scattered showers and
thunderstorms are thus expected on both Saturday and Sunday, with
the highest chances during the afternoon each day where diurnal
instability will be greatest.

King

&&

.AVIATION...
-- Changed Discussion --
(18Z TAFS)
Issued at 123 PM EDT Tue May 21 2024

VFR conditions will prevail through the TAF period. SCT/BKN cu in
the 4-6 kft range will diminish after 00Z with cu forming again
after 15-16Z Wednesday. ESE/SE winds at 4-8 kts will become near
calm overnight with direction becoming SSW after 12Z Wednesday at
3-6 kts.

//ATL Confidence...18Z Update...
High confidence.

RW
-- End Changed Discussion --

&&

.PRELIMINARY POINT TEMPS/POPS...
-- Changed Discussion --
Athens          61  88  64  89 /   0   0   0  10
Atlanta         65  88  68  89 /   0   0   0  10
Blairsville     59  82  61  82 /   0  10  10  30
Cartersville    63  88  66  89 /   0   0  10  10
Columbus        64  88  67  90 /   0   0   0   0
Gainesville     64  86  66  87 /   0   0   0  20
Macon           62  88  66  90 /   0   0   0   0
Rome            64  88  66  89 /   0   0  10  10
Peachtree City  61  88  66  89 /   0   0   0   0
Vidalia         63  88  67  91 /   0   0   0   0
-- End Changed Discussion --

&&

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

$$

SHORT TERM...KAL
LONG TERM....King
AVIATION...RW