573
FXUS62 KFFC 121854
AFDFFC

Area Forecast Discussion
National Weather Service Peachtree City GA
254 PM EDT Sun May 12 2024

...Afternoon Area Forecast Discussion...

.SHORT TERM...
(This afternoon through Monday)
Issued at 248 PM EDT Sun May 12 2024

At a glance:

 - Increasing cloudiness tonight, with rain spreading NE into the
   area late tonight and Monday morning.

 - Locally heavy rainfall possible across the S by late Monday.

Thick high clouds have shifted S to near and S of CSG and MCN.
Otherwise, skies are mostly sunny to partly cloudy with thinner high
clouds. Early afternoon temperatures ranged from the mid 60s over
the NE mountains to the mid 70s over the SE.

A weak upper ridge will build over the area tonight ahead of an
approaching upper low. This low will move from the Central Plains to
the central MS Valley by late Monday night. At the surface, low
pressure will lift NE into the mid-MS Valley. A warm front will begin
to lift NE from the Gulf Coast with fairly robust isentropic lift
spreading across the area from the SW and W. This will promote
lowering and thickening clouds tonight, with rain spreading into the
area late tonight and early Monday morning. The heaviest rainfall
rates are expected to set up closer to the warm front over the S
portion of the area, with 1 to 2 inches of rainfall likely near the
Columbus area by daybreak Tue. Most of the activity will start off as
showers, with scattered thunderstorms possible over the SW half of
the area by late Monday afternoon and Monday evening.

Low temperatures tonight will drop into the lower 50s across the NE
mountains, ranging to near 60 in the Atlanta metro area and lower
60s across the S. Due to the thickening cloud cover and rain, highs
on Monday will range from the mid 60s across the NE mountains to the
upper 70s across the extreme S. As rainfall continues Monday night,
overnight lows will only drop into the lower to mid 60s in most
locations, with some upper 50s in the NE mountains. /SEC

&&

.LONG TERM...
(Tuesday morning through next Saturday)
Issued at 248 PM EDT Sun May 12 2024

At a glance:

    - Bookend chances for showers and thunderstorms

    - Temperatures slightly below average

To kick off the extended range on Tuesday, a closed mid-level low
will be making its way across the Midwest. Mass response leads to the
formation of an accompanying surface low,and the combination of the
two will serve as the impetus for our first wave of rain (and storm)
chances. Much of the forecast -- especially as it pertains to chances
for severe weather -- will hinge on how far north the warm front
drifts during the day Tuesday. Kinematics (30-40kt jet at 850mb)
support the development of isolated strong to marginally severe
storms during the afternoon and evening, but should the frontal push
be further south than currently analyzed, the most unstable airmass
would be relegated to just portions of our far southern tier. On the
opposite side of the coin, a stalled front across south central
Georgia would serve as a source for continued re-development of
storms and an increased risk for flash flooding. Sandier soils south
of the Fall Line do require more precipitation before becoming
saturated, and current 36 hour rainfall totals are between 2-3" (with
locally higher amounts as high as 4"). With all that said, SPC
currently has the entire state under a Marginal (1/5) Risk for severe
weather, and WPC has outlined a Slight (2/4) Risk for excessive
rainfall south of the I-85/I-20 interchange. Better detail will be
available in coming model runs.

We`ll see clearing from south to north moving into Wednesday as mid-
level forcing exits and continues to sweep across the DelMarVa
region. Wraparound precipitation in the wake of the surface low is in
the cards for areas north of I-20 on Wednesday, but coverage will be
light and patchy, and additional QPF is expected to be low (<0.25").
A shortwave, low amplitude ridge moves in across the Ohio and
Tennessee River Valleys in the wake of Tuesday`s weather, and more
tranquil conditions are expected through Friday morning.

Beyond that, chances for showers and thunderstorms look to return
once again to close off the work week with the arrival of yet another
frontal system, but disagreement among global models precludes
giving much more detail than that.

Highs each day will be heavily dependent on cloud cover and
precipitation chances (or lack thereof). Tuesday, Wednesday, and
Friday -- the rainiest of the long term -- look to see highs top out
in the lower-70s to lower-80s (and mid 80s for far south central
Georgia). Otherwise, highs in the 80s. Lows will be fairly uniformly
in the upper-50s to 60s.

96

&&

.AVIATION...
(18Z TAFS)
Issued at 150 PM EDT Sun May 12 2024

VFR conditions will continue through the evening, with gradually
deteriorating conditions from the W after midnight tonight. Showers
will spread into CSG by daybreak, with rain spreading across the
remainder of the terminals through Mon morning. Have opted for lower
ceilings (IFR) in rain as model soundings look to be nearly saturated
in the lower levels at the expected onset of precipitation. Rainfall
is not expected to be too heavy through the end of the forecast
period other than at CSG. However, due to the expected moisture
levels in the boundary layer, vsbys may be further limited by fog.
Winds will be very light, although SE winds will begin to increase at
the end of the period.

//ATL Confidence...18Z Update...
Medium for timing of rain onset along with cig heights and vsbys
in rain, high for other elements.

SEC

&&

.PRELIMINARY POINT TEMPS/POPS...
Athens          56  71  61  75 /   0  70 100 100
Atlanta         60  69  62  77 /  30  80  90 100
Blairsville     52  67  57  69 /   0  60  90 100
Cartersville    57  71  61  77 /  30  80  90  90
Columbus        63  75  65  80 /  40  90  90 100
Gainesville     58  69  62  73 /   0  70  90 100
Macon           61  74  64  79 /  20  90  90 100
Rome            57  72  62  77 /  30  80  90 100
Peachtree City  59  70  62  78 /  40  90  90 100
Vidalia         64  77  65  81 /  10  70  90 100

&&

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

$$

SHORT TERM...SEC
LONG TERM....96
AVIATION...SEC