313
FXUS62 KFFC 060227 AAB
AFDFFC

Area Forecast Discussion...UPDATED
National Weather Service Peachtree City GA
1027 PM EDT Fri Jul 5 2024



...Evening Update...

.UPDATE...
Issued at 1010 PM EDT Fri Jul 5 2024

Scattered thunderstorms are continuing generally along and south
of I-20 late this evening, driven largely by colliding outflow
boundaries. These storms have been prolific lightning-producers,
and have produced wind gusts up to around 40 mph and torrential
downpours. Thinking that isolated to scattered storms will remain
likely through around midnight, especially across east-central
Georgia, as the larger-scale outflow spreads eastward. SPC
mesoanalysis reveals ~2000 J/kg of MLCAPE across this area at the
time of this writing, so additional strong storms with the
aforementioned hazards will be possible.

Martin


&&

.SHORT TERM...
(This afternoon through Saturday)
Issued at 256 PM EDT Fri Jul 5 2024

Key Messages:

 - Scattered thunderstorms will continue in the region this
   evening, with a few storms producing wind gusts at or above 40
   mph.

 - A Heat Advisory has been issued for portions of central and
   eastern Georgia for Saturday afternoon.

This Evening and Tonight:

Scattered thunderstorms will be the primary concern through this
evening. As of 2:45 PM a line of thunderstorms was moving through
northern Georgia. A weak cold from and fairly well developed cold
pool were the primary factors driving storm maintenance with this
line. Scattered diurnally driven showers and isolated
thunderstorms were ongoing ahead of the main line of storms in a
humid (dewpoints in the mid 70s) and hot (temperatures in the 90s)
environment. The SPC upgraded northern Georgia to a Marginal Risk
of severe weather earlier today. Given the current SPC
Mesoanalysis the environment remains a potential favorable for
isolated severe wind gusts in far northern Georgia where effective
shear was near 20 kt. Elsewhere a few isolated sub severe gusts
in the 25 to 40 mph range area possible, primarily as the main
line of storms marches east this evening.

Heat will remain a concern through this evening in the portions
of central and northern Georgia that have yet to see rainfall
today. A Heat Advisory remains in place for these areas, but it
has been cancelled for northwest Georgia where the rain has
already moved through. Observed heat index values in the 105 to
108 degrees are expected within the Heat Advisory.

More Storms and Rain on Saturday:

The aforementioned cold front will stall out somewhere near the
Interstate 85 Corridor on Saturday. This will set up a bifurcated
pattern of surface dewpoints in the region on Saturday. A drier
airmass should allow dewpoints to fall into the upper 60s in
northwest Georgia. Meanwhile soggy mid 70s dewpoints will linger
in central and eastern Georgia. Due to these higher dewpoints and
expected highs in the 90s, heat index values should climb back
above 105 degrees in portions of central Georgia Saturday. Thus a
Heat Advisory has been issued for the region. Scattered
thunderstorms should develop Saturday afternoon along and south of
the front. Severe weather is unlikely due to a lack of shear, but
locally heavy rainfall will be possible (1-3 inches). The storms
could limit heat index values in some areas.

Albright


&&

.LONG TERM...
(Sunday morning through next Thursday)
Issued at 256 PM EDT Fri Jul 5 2024

The long term forecast will be fairly typical for summer time in
the southeast, with daily rain and thunderstorm chances and hot
temperatures expected. As the subtropical ridge begins to break
down over the weekend, a broad 500mb trough will nudge a boundary
over the forecast area. This boundary will be relatively weak and
diffuse, and ultimately stall out across the area for much of the
week as the broad upper level troughing pattern persists. This
boundary will serve as the focal point for diurnally driven
showers and thunderstorms throughout the long term period, with
most days seeing scattered to numerous shows and thunderstorms
across the area. Abundant moisture will allow PWATs to surge into
the 2.0-2.5" range through much of the work week, which will
produce some concerns over locally heavy rainfall in any strong
storms that develop. Additionally, the moisture at the surface
will drive dewpoints into the mid to upper 70s for much of the
long term forecast period, resulting in triple digit heat index
values for many locations, particularly south of the I-85
corridor.

KAB


&&

.AVIATION...
(00Z TAFS)
Issued at 727 PM EDT Fri Jul 5 2024

Scattered SHRA/TSRA are impacting portions of central GA at the
time of this writing, so maintaining a TEMPO (including vsby
restrictions and erratic winds) until 03z at MCN and CSG. MVFR/IFR
cigs and patchy decreased vsbys are possible at all sites
overnight into tomorrow (Saturday) morning. SHRA/TSRA tomorrow
afternoon will generally be focused across central GA, but do have
a PROB30 at the northern TAF sites. Winds will be light to calm
overnight, becoming WNW to NNW at up to 7 kts tomorrow.

//ATL Confidence...00Z Update...
Medium confidence in cigs and vsbys, as well as SHRA/TSRA
tomorrow.

Martin


&&

.PRELIMINARY POINT TEMPS/POPS...
Athens          74  95  74  90 /  50  40  30  60
Atlanta         76  95  75  93 /  50  30  10  60
Blairsville     69  89  68  86 /  50  30  10  50
Cartersville    73  94  71  93 /  50  20  10  50
Columbus        76  95  76  93 /  60  70  30  70
Gainesville     75  94  74  90 /  50  30  20  60
Macon           76  95  74  90 /  40  80  40  60
Rome            74  95  72  95 /  50  20  10  50
Peachtree City  73  95  73  93 /  60  30  10  60
Vidalia         76  95  75  90 /  30  70  40  60

&&

.FFC WATCHES/WARNINGS/ADVISORIES...
Heat Advisory from noon to 8 PM EDT Saturday for GAZ027-036>039-
047>051-056>062-066>076-078>086-089>098-102>113.

&&

$$

SHORT TERM...Albright
LONG TERM....KAB
AVIATION...Martin