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650
FXUS62 KFFC 201740 AAA
AFDFFC

Area Forecast Discussion...UPDATED
National Weather Service Peachtree City GA
140 PM EDT Thu Jun 20 2024



...New 18Z Aviation Discussion...

.SHORT TERM...
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(Today through Friday)
Issued at 322 AM EDT Thu Jun 20 2024

Key Messages:

 - Dry weather will prevail in the region today.

 - Isolated afternoon and evening thunderstorms may return to
   central Georgia on Friday.

Today and Friday:

Dry weather will prevail in northern and central Georgia today as
easterly flow along the southern side of a ridge over the Mid-
Atlantic continues to advect in a relatively dry airmass. PW
values may creep back up over and inch is places this evening, but
for the majority of the day they will be below an inch. Combine
this with modest surface dewpoints and paltry mid level lapse
rates (700-500 mb lapse rates of 3.8 to 4.2 C/km), and instability
will be insufficient for convection today. Fair skies will help
high temperatures climb into the 88-93 degree range this
afternoon.

The upper level ridge will retrograde to the west tonight and
Friday, with the core of the ridge setting up along a line from
Texas to the Tennessee Valley by Friday afternoon. Meanwhile the
easterly wave (clearly visible on satellite this morning just
northeast of the Bahamas) will continue to push eastward, guided
by the prevailing flow around the ridge. The National Hurricane
Center has maintained a low probability (30% chance) of tropical
development with this feature over the next 48 hours. Given that
the majority of the model guidance favors little to no
intensification with this wave, their outlook seems quite
reasonable. One thing this wave will do is drive tropical moisture
back into our region Friday and Friday night (PW values rise back
above 1.5 inches). Showers and isolated thunderstorms could
develop in central Georgia by Friday evening as surface dewpoint
rise to near 70 degrees and a marginal amount of instability
develops (MUCAPE values from the HREF of 500 to 1250 j/kg). Lower
dewpoints should limit instability and keep northern Georgia dry
through Friday. High temperatures should climb by a couple of
degrees on Friday, especially in northern Georgia where less cloud
cover and lower dewpoints will aid diurnal heating. Afternoon
high temperatures in the 90 to 95 degree range are anticipated.

Albright
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&&

.LONG TERM...
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(Friday night through Wednesday)
Issued at 322 AM EDT Thu Jun 20 2024

Other than possible extreme heat conditions Monday-Wednesday,
major forecast concerns or significant weather impacts are not
expected in the long term period. Overall forecast confidence is
below normal.

Most recent guidance still continuing depiction of large E-W
oriented upper ridge waffling roughly from Southern Plains to the
Mid-Atlantic states Friday through Sunday. Depending on where
tropical low ends up, parts of the area could be very moist with
widespread diurnal convection on Sat and Sun. GFS and EC members
do bring in tropical low well inland over S Georgia and N Florida
while GEPS and SREF keep most of it over the Atlantic. Even
without a strong consensus and relatively strong upper ridge just
to our north, will still need 20-40% PoPs this weekend.

By Monday, vast majority of guidance members show large scale
troughing over the E CONUS and ridging centered over the SW US
resulting in weak NW flow along with some hints at MCS development
esp late Tues and Wed over mid-South. Without a big push of dry
air, will also have some sct diurnal convection even with NW flow.
In theory, daytime temps should be a tad cooler in this pattern
but guidance really sticking with above normal temps, perhaps due
to the very dry soil and vegetation conditions we are
experiencing. Dewpoints also will be quite high with resulting
heat index values approaching heat advisory criteria Mon-Wed. NBM
dewpoints have been shown to have a high bias during warm-season
heat waves so may need to adjust them as we approach the potential
heat event.

Outside of the tropical wave off the FL peninsula forecast to
move toward the Georgia coast late Thurs and Fri, no tropical
activity is expected over the region at this time.

SNELSON
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&&

.AVIATION...
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(18Z TAFS)
Issued at 122 PM EDT Thu Jun 20 2024

VFR conditions are expected at all TAF sites through the period.
The Cu field (045-065) will persist until early evening. Easterly
winds will stay breezy around 10-15 kts with gusts of 20-25 kts,
then decrease to around 5 kts or lower overnight. Winds will pick
back up mid/late tomorrow (Friday) morning out of the ENE to E at
7-12 kts with gusts around 20 kts possible. FEW/SCT clouds around
050-060 are expected tomorrow afternoon.

//ATL Confidence...18Z Update...
High confidence on all elements.

Martin
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&&

.PRELIMINARY POINT TEMPS/POPS...
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Athens          65  93  69  93 /   0   0   0  20
Atlanta         69  94  72  94 /   0   0   0  20
Blairsville     63  87  65  89 /   0  10   0  20
Cartersville    67  94  69  96 /   0   0   0  20
Columbus        69  95  73  95 /   0   0  10  30
Gainesville     67  91  70  92 /   0   0   0  20
Macon           66  94  71  95 /   0  10  10  30
Rome            69  95  70  96 /   0   0   0  20
Peachtree City  66  94  69  94 /   0   0   0  20
Vidalia         68  92  73  93 /  10  50  20  60
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&&

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

$$

SHORT TERM...Albright
LONG TERM....SNELSON
AVIATION...Martin