Shannon, Georgia Weather Forecast Discussion

310
FXUS62 KFFC 200747
AFDFFC
Area Forecast Discussion
National Weather Service Peachtree City GA
347 AM EDT Sat Sep 20 2025
...Morning Area Forecast Discussion...
.SHORT TERM...
(Today through Sunday)
Issued at 302 AM EDT Sat Sep 20 2025
Key Messages:
- Isolated afternoon and evening showers and thunderstorms.
- Warm, above normal temperatures persist.
Mostly clear skies with some patchy areas of fog this morning
across north and central GA. High pressure is still in place
across the region but we will see another round of isolated
showers and thunderstorms this afternoon and evening. Like
yesterday...there is no major feature like a frontal boundary for
this convective activity to focus on. The storms will begin to
generate off the residual moisture from the easterly flow and
high temps in the upper 80s to lower 90s. The highest elevations
in northeast Georgia generally have the best chances of seeing
storms, with orographic lift helping the convective process. Any
storms that develop should stay below severe limits with
instability indices staying fairly weak and the high pressure
ridge helping to cap things off. This ridge builds in a bit
stronger Sunday so expecting less convective coverage if we see
any storms at all. Because of this wedge like ridge building in
stronger Sun, High temps will be a few degs cooler (mainly upper
80s) Sun than Today.
01
&&
.LONG TERM...
(Sunday night through Friday)
Issued at 302 AM EDT Sat Sep 20 2025
Key Messages:
- Increasing chances for rain and thunderstorms return starting
Wednesday through Friday, with widespread rainfall possible on
Thursday and Friday.
- Above average temperatures through midweek, followed by
temperatures closer to average late in the week.
On Sunday night into Monday morning, a longwave trough will extend
from the western Great Lakes towards the Lower Mississippi River
Valley. As it progresses eastward, it will force upper level
ridging and associated surface high pressure eastward into the
Atlantic. As period begin, a CAD wedge will be in place along the
Appalachians and over north Georgia, which will weaken throughout
the day as the surface high retreats further to the east. Drier
air will be in place across much of the forecast area due to the
influence of the wedge, which will largely inhibit chances for
showers and thunderstorms on Monday afternoon, with isolated
showers and thunderstorms only forecast across the far northern
tier. With the position of the high being well to the north and
east of the forecast area, it appears that it will be too far away
for us to tap into the cooler air we may normally see in this
kind of pattern. Highs on Monday afternoon are thus forecast to
rise into the mid 80s to near 90 across the majority of the
forecast area, with the exception of the far northeastern
mountains, which will be slightly cooler.
Southwesterly mid and upper level flow will set up over Georgia
ahead of the approaching trough, which will lead to advection of
warm and moist air into the area. After the morning begins in the
low to mid 60s on Tuesday morning, highs will rise into the upper
80s to low 90s during the afternoon. Isolated to scattered showers
and thunderstorms will be possible once again as the trough axis
moves across the area, most likely to the north of I-20. After this
point, the forecast becomes a bit tricky through the end of the
week. Guidance is beginning to come into better agreement on a
cutoff upper low over the central Great Lakes, with a shortwave
swinging southeastward through the Great Plains and around the
periphery of this low on Tuesday night. At the very least, this
setup will keep Georgia underneath southwesterly flow aloft through
midweek, which will contribute to the warmest day across the
majority of the forecast area on Wednesday, with highs between 6-10
degrees above daily normals and even reaching into the mid 90s in
central Georgia during the afternoon. Dewpoints will meanwhile rise
into the upper 60s to low 70s.
After developing the shortwave over the Great Plains into a cutoff
low, itself, a surface low is anticipated to develop near the
Ozarks. Beyond this point, the developing low pressure system is
likely to move northeast, but guidance remains inconsistent with
respect to its position and movement. A cold front extending
southward from the surface low is then expected to slowly advance
eastward towards the forecast area, with chances for thunderstorms
increasing accordingly late Wednesday through Friday. At this time,
PoPs are between 40-60% at the highest through this time period to
account for lingering uncertainty and run to run inconsistency still
exhibited by the models. The coverage of precipitation and rainfall
amounts will ultimately depend on the position and evolution of the
upper level cutoff low and how it influences the surface low, which
will warrant continued monitoring as the pattern evolves. Increased
coverage of showers and thunderstorms combined with the advance of
the cold front is likely to promote cooling temperatures late in the
period.
King
&&
.AVIATION...
(06Z TAFS)
Issued at 215 AM EDT Sat Sep 20 2025
Mostly clear skies expected across the area this TAF period. We
could see some isolated areas of Haze around sunrise but only
expecting VSBYs to get down to 5 statute miles. We will also see
some isolated SHRA/TSRA this afternoon but thinking they will be
isolated enough to leave it out of the TAF. Winds are light and
variable this morning but will be mainly out of the E to SE in the
3-7kt range this afternoon and evening.
//ATL Confidence...06Z Update...
Confidence high on all elements
01
&&
.PRELIMINARY POINT TEMPS/POPS...
Athens          86  64  85  63 /  20  10   0   0
Atlanta         90  69  88  67 /  20  10   0   0
Blairsville     81  61  79  60 /  30  10  20  10
Cartersville    91  67  89  66 /  20  10  10  10
Columbus        94  69  92  67 /  20  10   0   0
Gainesville     88  65  85  65 /  20  10  10  10
Macon           90  66  89  64 /  20  10   0   0
Rome            93  67  90  67 /  20  10  10  10
Peachtree City  91  65  88  65 /  20  10   0   0
Vidalia         91  66  89  65 /  20  10   0   0
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SHORT TERM...01
LONG TERM....King
AVIATION...01

NWS FFC Office Area Forecast Discussion