Nelson, Georgia Weather Forecast Discussion

045
FXUS62 KFFC 202334
AFDFFC
Area Forecast Discussion
National Weather Service Peachtree City GA
734 PM EDT Sat Sep 20 2025
...New 00Z Aviation Discussion...
.SHORT TERM...
(This afternoon through Sunday)
Issued at 242 PM EDT Sat Sep 20 2025
Key Messages:
- Isolated to widely scattered afternoon and evening rain and
    thunderstorm chances (15-25% chance) through the afternoon.
    Isolated storm chances confined to North Georgia on Sunday.
- Warm, slightly above normal temperatures persist through Sunday.
Discussion:
Overall, a rinse and repeat forecast for today. Cumulus has started
to bubble and develop across North and Central Georgia this
afternoon. Isolated showers and storms have also begun to develop
across the higher terrain in the northeast and across eastern
Georgia. Still anticipating slightly better coverage of showers and
storms through early evening though chances still hover between 15-
25%. The highest chances (~25% chance) for showers or storms today
will be in northeast Georgia where terrain will aid in development.
While no severe storms are expected due to poor lapse rates and lack
of wind shear, daytime mixing could support an isolated downburst
with winds nearing 40 MPH. Thus, keep your eyes to the skies as
you`re partaking in your weekend festivities.
Surface high pressure will become wedged along the Appalachians
resulting in a wedge like setup for Sunday, largely inhibiting any
rain chances. Latest HREF guidance suggests increasing cirrus across
the area early Sunday. Thus morning lows may be a degree or two
warmer. With increasing clouds, daytime temperatures for Sunday are
likely to be 2-4 degrees `cooler`. Forecast highs in the mid 80s to
right around 90 are favored across most locations and highs in the
70s favored in the mountains for Sunday.
07
&&
.LONG TERM...
(Monday morning through next Friday)
Issued at 242 PM EDT Sat Sep 20 2025
Key Messages:
- Chances of seeing decent rainfall by the end of the coming
    week continues to increase.
- Temperatures well above average to start the week, finishing
    at or even below average thanks to rain and cloud cover by
    the end.
Forecast:
Seeing a lot more consistency and model agreement across the
ensembles this afternoon with regards to the upper level pattern
that is expected to play out over the coming week. Weak trough aloft
will be in place to start the long term on Monday as noted by
relative cool 500 mb temps and lowered tropopause heights. This
combined with plenty of surface heating that should bring afternoon
temps well into the upper 80s to near 90 will allow for some
isolated afternoon thunderstorms. Best chances will be across far
north Georgia right now, where moisture will be a bit better and
terrain may aid initiation.
Monday night into Tuesday, an anticyclonic rossby wave break along
the anticyclonic side of the jet is progged over the NW CONUS that
will help chop a bit of lower theta PV off of a TPV over western
Canada. This anomaly will become a cut off upper level low that
should dig into the Great Plains and continue to dig southeast
towards the CWA Wednesday into Thursday. This upper level system
will be the big player in our rain chances from the middle to end
of the week. Ensembles are in pretty good agreement now around the
evolution described above, with both Euro and GEFS showing strong
signal for the cut off low with 500 mb height fields even this
far out. Questions that will remain will be with regard to the
exact position and timing of the upper level low, as well as how
long it sticks around. Given our position relative to the low,
getting some amount of beneficial rainfall seems likely, however.
Just a matter of how much.
Looking at the ensemble probabilities, mean rainfall across the time
period has a quarter to half an inch across central Georgia, moving
to half an inch to over an inch across northern Georgia. 90th
percentile output may give a better idea of convective potential
within storms that do form, showing an inch and a half to over 3" in
a 72 hour period that ends next Saturday morning. On the other side
of the coin, the 10th percentile likely represents a system that
doesn`t deep or dig as much into the area and is unable to tap into
moisture. This still shows some rainfall across north Georgia, but
only very light amounts generally under a quarter of an inch.
The final thing to talk about will be temperatures, which will look
now like they will be 8-10 degrees above average for highs Monday,
Tuesday, and Wednesday across the area, which will give us afternoon
temps in the upper 80s and low 90s. With rain and cloud cover
expected to move in, things cool down towards the end of the week,
and highs in some areas, including the metro, may struggle to get
above 80.
Lusk
&&
.AVIATION...
(00Z TAFS)
Issued at 729 PM EDT Sat Sep 20 2025
Any lingering iso SHRA will quickly diminish through 01Z, and VFR
will prevail through the period. Only a stray SHRA/TSRA is
possible Sunday PM with dry conditions favored. Overnight calm to
light SE/E winds will remain SE through the day Sunday at 4-8 kts.
//ATL Confidence...00Z Update...
High confidence.
RW
&&
.PRELIMINARY POINT TEMPS/POPS...
Athens          64  85  63  86 /  20   0   0   0
Atlanta         68  87  67  88 /  20  20   0   0
Blairsville     61  79  60  80 /  20  20  10  20
Cartersville    67  89  67  89 /  20  20  10  10
Columbus        69  91  67  91 /  20  20   0   0
Gainesville     66  85  64  86 /  20  10   0  10
Macon           66  88  64  89 /  20   0   0   0
Rome            66  90  67  89 /  20  20  20  20
Peachtree City  66  88  64  88 /  20  20   0   0
Vidalia         66  90  65  89 /  10   0   0  10
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SHORT TERM...07
LONG TERM....Lusk
AVIATION...RW

NWS FFC Office Area Forecast Discussion