190
FXUS62 KFFC 240059
AFDFFC

Area Forecast Discussion
National Weather Service Peachtree City GA
859 PM EDT Thu Jul 23 2026

...Late Evening Update...

.KEY MESSAGES...

  - A Flood Watch remains in effect through late Friday evening
    across portions of north Georgia.

  - The threat for heavy rainfall and flash flooding will
    remain elevated across north Georgia through Saturday in the
    presence of a stalled front.

  - Heat concerns rebound in earnest next week with an upward
    trend in temperatures and heat indices by Monday.

&&

.UPDATE...
Issued at 846 PM EDT Thu Jul 23 2026

A conveyor belt of showers and isolated thunderstorms persist
along and in the vicinity of a frontal boundary that is currently
draped from Summerville to Dahlonega (North GA). The occurrence
of lightning has been few and far between so far perhaps due to
the presence of more cloudy conditions through a better part of
the afternoon. Most of the lightning that has been observed has
been to our west in Central AL and to our northeast in South
Carolina. Due to the lack of lightning overall rain rates remain
low (less than half an inch). Latest hi-res have at least some
showery activity persisting through most of the overnight period,
with increasing coverage by mid-morning. Where thunder does occur
overnight, localized heavy rainfall may result given the tropical
airmass that still remains in place. Thus, some isolated instances
of flash flooding are still possible in North GA overnight. No
changes were made to the Flood Watch -- the greatest risk for any
flooding across North GA will be on Friday (tomorrow).

&&

.SHORT TERM...
(This afternoon through Friday)
Issued at 158 PM EDT Thu Jul 23 2026

Scattered showers and thunderstorms are beginning to form over
northern Georgia as the front is slowly sinking southward. Coverage
is expected to increase into the evening and overnight as we begin
to transition the flow. As the trough to our north begins to shift
slightly eastward, a surge of energy pushes through the flow into
our area that will help enhance the precipitation we will have
ongoing along the frontal boundary over north Georgia. With this
frontal boundary stalled out through Saturday we are likely to see
increased rain amounts with 1-3 inches possible with locally up to 4-
5 inches. This will be highly dependent on where storms are able to
lock onto the terrain and or where storms are able to train in one
area for a long time period. The flood watch is currently in effect
through Friday at midnight but this could be extended into Saturday
if the heavy rain threat is expected to linger into the weekend. The
expansion of the watch will be heavily dependent on what happens
into the afternoon and evening and the later model suite. Our
current confidence in flash flooding lies in the current watch area.

One positive of the increased rainfall is increased cloud cover.
This will ultimately lead to decreased heat indices at least for
north Georgia. Today they should top out in the upper 90s to near
100, but tomorrow will see heat indices in the low to mid 90s for
north Georgia and up to ~100 for the remainder of the area.
Temps will be in the mid to upper 80s for far north Georgia and low
to mid 90s for the remainder of the area.

&&

.LONG TERM...
(Saturday morning through next Wednesday)
Issued at 158 PM EDT Thu Jul 23 2026

Saturday starts with the pattern in transition from a weak westerly
flow to a full fledged North to northwest flow around a significant
western ridge setting up.  500mb flow within the models while fairly
consistent at indicating a disturbance within the flow moving
our direction, are very inconsistent in how convection evolves
along and ahead of that disturbance. Of the CAMS which reach into
early Saturday many suggest a TS complex diving SE through the
mid MS valley but differ on how and where the bulk of the activity
is located. As a result, NBM pop guidance for Sat is fairly high
~60pct but the spread is fairly significant amongst the many
members ranging from 10pct to 70pct...likely due to the
uncertainty the NW flow pattern brings. This yields a fairly low
confidence pop forecast for Saturday ranging everywhere from
mostly dry to decent storm coverage.

Likewise, the remainder of the extended period from Sunday to
Wednesday locks the area into a solid N to NW flow aloft...and a
more uncertain pattern in terms of sensible weather. Ensemble
means of the GFS and ECMWF attempt to identify individual
vorticity maxima sliding SE around the eastern periphery of the
western ridge suggesting that some "waves" will be present, but
suspect the blending within the means are dampening any singular
signal out. Single model runs, (GFS,CMC,ECM etc) all suggest
disturbances, aka ridge riders, within the mean NW flow rotate
around the ridge and southeast into the area during the period.
Given the pattern and the instability in place, would not be
surprised to see shower/storm chances increase each day with time.
Current WPC and NBM guidance is less than 10 pops Monday and
Tuesday, but the spread within the guidance ranges from 0 to 30pct
meaning some of the guidance is catching onto the prospect of
activity in the flow. From prior history of summer ridges, ala
summer of 2023, we need to keep our guard up. CSU and NCAR ML
guidance also recognizes the pattern and at least suggest some
severe probs possible..esp Tue and Wed with deep N flow and plenty
of instability. In short, will need to keep an eye on Mon- Wed
period for severe risk within the NW flow regime.

Despite being in NW flow, the surface dpts remain elevated in the
low to mid 70s through the period.  Combined with increasing temps,
expect Apparent T`s to slowly increase and peak by Tue and Wed.
Baring relief from rain, guidance suggests Heat Advisory is likely
need Mon - Wed across a large portion of the fcst area, but
particularly along and south of I-20 where HI values range from 105-
108 each day.

&&

.AVIATION...
(00Z TAFS)
Issued at 721 PM EDT Thu Jul 23 2026

Mostly VFR to start off with sct SHRA and very iso TSRA moving
thru the northern sites. Should continue thru at least 02-03z
before tapering though even iso shra may continue thru the night.
MVFR cigs return to the northern sites by 08-10z lasting thru at
least 16z, and IFR psbl btwn 11-14z. Less certain about MVFR/IFR
potential at MCN/CSG given lack of shra/tsra today. Increasing
shra potential after 12z and tsra by around 17z for northern
sites. SHRA/TSRA may hold off until late afternoon (beyond 20z)
for MCN/CSG.

//ATL Confidence...00Z Update...

Medium confidence on all elements.

07

&&

.PRELIMINARY POINT TEMPS/POPS...
Athens          72  87  72  88 /  50  70  40  50
Atlanta         75  88  74  88 /  30  60  20  60
Blairsville     67  81  67  81 /  70  80  30  60
Cartersville    73  87  72  88 /  60  80  30  60
Columbus        76  94  76  93 /  10  20  20  50
Gainesville     72  85  72  87 /  70  80  40  50
Macon           75  93  74  91 /   0  20  10  60
Rome            72  86  72  87 /  60  80  30  60
Peachtree City  74  88  73  89 /  20  50  20  60
Vidalia         75  97  75  94 /   0  20  10  60

&&

.FFC WATCHES/WARNINGS/ADVISORIES...
Flood Watch through Friday evening for GAZ001>009-011>016-
019>024-030.

&&

$$

SHORT TERM...Hernandez
LONG TERM....30
AVIATION...07