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884
FXUS62 KFFC 051032
AFDFFC

Area Forecast Discussion
National Weather Service Peachtree City GA
632 AM EDT Wed Jun 5 2024



...New 12Z Aviation Discussion...

.SHORT TERM...
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(Today through Thursday)
Issued at 404 AM EDT Wed Jun 5 2024

500 mb analysis reveals several vort maxes within the overall
shortwave-troughing pattern over the Southeast. Isolated to
scattered showers and a few thunderstorms have been occurring
across portions of the CWA overnight amid the humid, weakly-forced
environment, as well as upstream across portions of AL. Will
likely see isolated showers continue through the remainder of the
morning hours. Additionally, areas of fog have developed across
portions of north GA, with dense fog in portions of Gwinnett,
Barrow, Jackson, and Hall Counties.

These vort maxes will shift eastward through the day, and with
the help of daytime heating, scattered showers and thunderstorms
are expected this afternoon and evening. SREF progs MUCAPE
reaching 1000- 1500+ J/kg and hi-res models prog mid-level lapses
of 6.5 to near 7 deg.C/km, so updrafts should have no problem
getting going. That said, 0-6 km bulk shear generally less than 30
kts will limit storm organization/intensity. SPC has the entire
CWA outlooked in a General Thunder risk, which makes sense, as the
aforementioned ingredients suggest the possibility of a few
strong storms (with locally heavy rainfall, frequent lightning,
gusty winds, and small hail) but not much of a severe weather
(damaging wind and large hail) threat. Any slow-moving storms or
back-building storms that are especially efficient rainfall-
producers could cause localized flooding, especially across north
GA, where flash flood guidance is lower and soil moisture is
greater.

As the shortwave axis shifts eastward over the CWA overnight,
scattered showers and thunderstorms will continue. HREF and hi-res
models suggest decent instability (500-1000 J/kg) and mid-level
lapse rates of 6.5 to 7.5 deg.C/km, so the potential for a few
strong storms will persist overnight.

The flow aloft will become northwesterly tomorrow (Thursday), and
at the surface, a weak front will push into north GA. The day
will start off with essentially CWA-wide 30% to 50% PoPs, with
PoPs becoming maximized (60% to 70%) mainly along and south of
I-20 in the afternoon and evening, ahead of the front where
instability and PWAT will be greatest. SPC has the entire CWA
outlooked in a General Thunder risk again tomorrow, which makes
sense given these ingredients plus little to no 0-6 km bulk shear.
A few strong storms will be possible with the aforementioned
hazards, especially across central GA, where mid-level lapse rates
are progged to be 6.5 to around 7 deg.C/km.

As far as temperatures go, morning lows will be in the mid-60s to
lower 70s, and afternoon highs will be in the lower 80s to around
90.

Martin
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&&

.LONG TERM...
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(Thursday night through Tuesday)
Issued at 404 AM EDT Wed Jun 5 2024

The long term period starts off with a bang, as a double-barreled
cold front sweeps across the area Thursday night. Shower and
thunderstorm activity is forecast to be shunted SE by the initial
front, with isolated to low end scattered activity SE of Macon
Thursday evening. Cooler air will filter into the area behind the
secondary front. As a result, Friday morning lows will only be
about 3 to 5 degrees cooler than Thursday morning`s. With more
sunshine Friday versus Thursday, Friday`s high temperatures will
be a bit warmer. However, minimum relative humidity values Friday
afternoon will be a full 30% lower than on Thursday. As a result,
Friday will feel more comfortable.

The big story will be lows Saturday morning. Forecast daybreak
temperatures will range from the mid 50s in the NE mountains to
the mid 60s in the extreme SE portion of the County Warning Area.
Due to the urban heat island effect, lows in the Atlanta metro
will be in the lower 60s, but some of the suburbs will drop into
the upper 50s. Dry air on Saturday will continue to make
temperatures more bearable.

After a brier warm-up, another upper level trough and associated
surface front will approach the area from the NE late in the
weekend. Showers and thunderstorms ahead of the front will enter
NE GA late Saturday night, with precipitation spreading across the
remainder of the area on Sunday. The best chance of rain will be
Monday afternoon across the S portion of the area as the front
works on daytime instability. Rain will come to an end behind the
front from the NW late Monday night and Tuesday, as drier and
slightly cooler air filters in. /SEC
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&&

.AVIATION...
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(12Z TAFS)
Issued at 618 AM EDT Wed Jun 5 2024

OCNL MVFR/IFR cigs have spread over AHN, PDK, and RYY, so have
TEMPOs at ATL and FTY until 14z for low cigs out of prudence.
Improvement in cigs is expected after 14z-15z. Sct`d Cu field is
expected this afternoon along with iso`d/scat`d SHRA and TSRA
(which are covered by a PROB30 at all sites). For ATL, winds look
to stay light and SSE until mid-morning or so, after which winds
will become SSW to SW at 5-10 kts. Iso`d SHRA/TSRA are expected to
persist overnight with MVFR/IFR cigs early tomorrow morning.

//ATL Confidence...12Z Update...
Medium confidence on morning cigs progression and timing/coverage
of afternoon SHRA/TSRA. High confidence on all other elements.

Martin
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&&

.PRELIMINARY POINT TEMPS/POPS...
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Athens          69  85  66  85 /  40  40  10   0
Atlanta         71  86  68  85 /  50  50  10   0
Blairsville     65  80  60  77 /  50  50  10   0
Cartersville    68  86  64  84 /  50  40  10   0
Columbus        72  86  70  91 /  50  60  10  10
Gainesville     69  85  66  82 /  50  40  10   0
Macon           71  86  69  90 /  40  70  10  10
Rome            69  87  65  85 /  50  30   0   0
Peachtree City  69  87  66  87 /  50  50  10   0
Vidalia         72  89  71  92 /  40  70  30  10
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&&

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

$$

SHORT TERM...Martin
LONG TERM....SEC
AVIATION...Martin