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989
FXUS62 KFFC 210801
AFDFFC

Area Forecast Discussion
National Weather Service Peachtree City GA
401 AM EDT Fri Jun 21 2024


...Morning Area Forecast Discussion...

.SHORT TERM...
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(Today through Saturday)
Issued at 340 AM EDT Fri Jun 21 2024

As the morning begins, a broad upper level ridge remains
positioned over much of the eastern CONUS. Much of the Southeast
is under the influence of surface high pressure and relatively dry
air underneath this ridge. Meanwhile, a small but concentrated
area of showers and thunderstorms is ongoing in association with a
low pressure roughly 200 mi to the east of the Georgia/Florida
coast. As the ridge pattern retrogrades to the west and begins to
dampen, the disturbance will be steered to the west-northwest at
around 10-15 mph by the flow around this ridge. The NHC currently
gives this disturbance a 50% chance of tropical development in the
next 48 hours, as environmental conditions are marginally
conducive to further development into a short-lived tropical
depression.

In the meantime, low temperatures will start the morning in the
mid to upper 60s across the majority of the area, and conditions
across north and central Georgia will remain dry through the
morning. With only scattered cloud cover developing in the
afternoon and increasing 1000-500 mb thicknesses in the high-
pressure regime, high temperatures will climb into the low to mid
90s this afternoon, with the exception of cooler temperatures in
the higher elevations of far northeast Georgia. As the disturbance
draws closer to the coast by this afternoon, it will bring an
influx of tropical moisture into east-central Georgia, with
dewpoints increasing into the upper 60s to low 70s and
precipitable water values increasing to above 1.5" in the far
southeast corner of the forecast area. The increase in atmospheric
moisture, combined with MUCAPE values of 500-1000 J/kg will be
sufficient for isolated to scattered thunderstorms in east-
central Georgia - to the immediate west of the advancing low - in
the afternoon hours today. The absence of any notable low level
shear or deep-layer bulk shear suggests that the development of
strong to severe thunderstorms will be unlikely this afternoon.

By Friday evening, the center of the low is anticipated to be
centered near the Georgia/Florida coast, at which point it is
likely to begin to slowly meander northward Friday night and into
Saturday. Moisture advection will persist overnight and into
Saturday as dewpoints in the 70s and precipitable water values
between 1.5-1.7" continue to spread further north and west into
the forecast area. High temperatures will also continue their
steady climb, reaching into the mid 90s across the majority of the
forecast area on Saturday afternoon. The combination of warming
temperatures and increasing moisture could have heat index values
pushing 100 in some locations. The combination of increasing
moisture, MUCAPE values between 750-1250 J/kg, and frictional
convergence near around the low pressure system will lead to a
greater chance of showers and thunderstorms on Saturday. At this
time, PoPs are mainly confined to the south of the I-85 corridor
where these ingredients all come together. The coverage of showers
and thunderstorms will be greatest in the far southeast (likely
PoPs), with progressively lower coverage to the north and west.

King
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&&

.LONG TERM...
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(Saturday night through Thursday)
Issued at 340 AM EDT Fri Jun 21 2024

No significant weather impacts or forecast concerns are expected
in the long term period.

Most recent medium range guidance still has large E-W oriented
ridge in place over 30-35 deg N latitude over the CONUS thru
Monday at which point strong upper ridging builds in the SWUS and
W TX and weak troughing over the eastern CONUS including Georgia
and Carolinas. Could see a weak front try to slip in Sun night and
early Monday with some lingering overnight convection. Not seeing
anything too strong with the storm environment at this time.

Models also showing a more pronounced wave very late in the
forecast moving SE in NWly flow from the Midwest states into the
SEUS on Wed. As mentioned previously, this NW flow pattern on the
east side of a strong upper ridge is favorable for MCS development
and maintenance overnight. Global ensembles still show signs this
may occur, Tues night, Wed and/or Wed night. Most favorable area
for more significant strong/severe storms may end up to our west
but still plenty of time for new observations upstream to adjust
later forecasts.

Also not seeing any clear tropical activity in the Atlantic basin
or GOM through the long term period. May become more active
around the end of the month over the Caribbean but that remains
very uncertain.

SNELSON
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&&

.AVIATION...
(06Z TAFS)
Issued at 139 AM EDT Fri Jun 21 2024

VFR conditions are expected to persist through the TAF period,
with a FEW-SCT cu field around 050-060 developing during the
afternoon hours. Chances for SHRA/TSRA are forecast to remain
south and east of all TAF sites today. Winds will be primarily E
through the period, at 5 kts or less during the morning hours and
increasing to 7-10 kts after 17Z, then diminishing after sunset.

//ATL Confidence...06Z Update...
High confidence on all elements.

King

&&

.PRELIMINARY POINT TEMPS/POPS...
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Athens          92  69  93  72 /   0   0  10  10
Atlanta         93  71  95  75 /   0   0  10   0
Blairsville     86  64  89  67 /  10  10  10   0
Cartersville    93  69  95  72 /   0   0  10   0
Columbus        95  72  96  74 /   0   0  20  10
Gainesville     90  69  93  72 /   0   0  10   0
Macon           94  71  94  72 /   0   0  30  10
Rome            94  71  97  72 /   0   0  10   0
Peachtree City  93  69  95  72 /   0   0  10   0
Vidalia         91  74  91  73 /  40  30  80  20
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&&

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

$$

SHORT TERM...King
LONG TERM....SNELSON
AVIATION...King