Chamblee, Georgia 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

597
FXUS62 KFFC 191033
AFDFFC

Area Forecast Discussion
National Weather Service Peachtree City GA
633 AM EDT Sat Jul 19 2025

...New 12Z Aviation Discussion...

.SHORT TERM...
(Today through Sunday)
Issued at 355 AM EDT Sat Jul 19 2025

Key Messages:

- Isolated to scattered thunderstorms expected each afternoon and
  evening, with the greatest coverage likely across north Georgia.

- Continued heat and humidity, with heat index values ranging
  from the upper 90s to just shy of 105 degrees across much of the
  forecast area.

Discussion:

Our persistent friend, the subtropical ridge, remains firmly in
place across the Southeast. PWAT values will range from 1.6" to
2.0" through the short term period, which -- when coupled with
ample daytime heating and destabilization -- will support isolated
to scattered showers and thunderstorms each afternoon and early
evening. While warm temperatures aloft will hinder widespread
strong to severe storms, like yesterday, a few strong storms with
localized damaging wind gusts and frequent lightning will be
possible. Additionally, torrential downpours can be expected with
storms both today and tomorrow (Sunday) as the environment is very
soupy (the well-saturated atmospheric column in the 00z FFC
sounding illustrates this). WPC (Weather Prediction Center) has
clipped far north Georgia with a Slight Risk (level 2 out of 4)
for heavy rainfall leading to localized flash flooding today, with
a Marginal Risk (level 1 out of 4) across much of the remainder
of north Georgia. Another Marginal Risk is in place tomorrow
across north Georgia. These risk areas are warranted as rain
chances are maximized across north Georgia both days and near-
surface soil moisture is greatest here. On the flip side of the
coin (and as was observed yesterday) portions of east-central
Georgia may go both days without any rain given the proximity of
the high pressure center associated with the subtropical ridge.

Heat index values are forecast to range from the upper 90s to
just shy of 105 degrees across much of north and central Georgia
both days. Across portions of eastern and central Georgia, heat
index values may briefly hit 105 to 107 degrees, but at this time,
the expected isolated nature of said values does not warrant Heat
Advisory issuance.

Martin


&&

.LONG TERM...
(Sunday night through Friday)
Issued at 355 AM EDT Sat Jul 19 2025

Key Messages:

- Hot and humid conditions expected areawide early in the period.
  Heat Advisory issuance is likely for portions of the area
  Monday and Tuesday.

- Chances for showers and thunderstorms each afternoon through the
  extended, with greatest coverage Tuesday to Wednesday.

Discussion:

Much of the sensible weather in the extended range will be
governed by a mid-level subtropical ridge parked atop the
Southeast. A pocket of deep moisture rotating around the eastern
edge of the aforementioned ridge will support the development of
diurnal showers and storms -- likely to exceed "typical"
summertime afternoon coverage as it nudges into the forecast area
proper by midweek. Coincident with the arrival of best moisture
throughout the column, a lobe of surface high pressure slides into
place across New England Tuesday into Wednesday. As it does so, a
backdoor cold front is pushed southwestward along the expanding
U-shaped isobars that characterize the wedge. Thunderstorms are
likely to quasi-organize along the advancing front, potentially
resulting in an east-to-west storm motion that is anomalous for
our area. It remains to be seen how much oomph the front has/how
far west it progresses. Global model guidance suggests
comparatively drier air will be ushered in aloft in the wake of
our midweek convective peak, not quite enough to completely scour
out chances for thunderstorms, but enough to bring them back down
to the low-end chance range (20-40%) for much of the area from
Wednesday on. As the frontal energy settles along the northern
Gulf, some semblance of a baroclinic zone is likely to linger for
the remainder of the week, resulting in higher PoPs along our far
southern tier/in closest proximity to best remnant forcing. Given
abundant moisture, any storm that forms through Wednesday will be
capable of producing locally heavy rainfall and nuisance flooding
of low-lying, impermeable, or flood-prone areas. A Marginal (level
1 out of 4) Risk for Excessive Rainfall is in effect for much of
north and central Georgia on Monday and Tuesday. Widespread flash
flooding is not anticipated, but isolated instances are possible,
namely for locales that find themselves under especially strong or
slow-moving storms.

With little in the way of deep layer kinematic support to provide
meaningful chances for severe weather, the primary hazard of
concern for the first half of the long term will be heat. Highs
Monday and Tuesday will be in the mid-to-upper 90s for all bur far
northeast Georgia, which will remain in the 80s. Combined with
dewpoints progged to surge into the mid-70s are perhaps higher,
heat index values are likely to eclipse 105 degrees for large
swaths of the area. Heat Advisory issuance will likely be
necessary Monday and Tuesday.

For Wednesday and Thursday, drier air post-front will allow
dewpoints to drop into the mid-60s to lower-70s, supporting a
brief reprieve from truly oppressive humidity. With highs expected
to remain in the lower 90s, this forecaster wouldn`t call it a
pleasant latter half of the week, but it will certainly be
slightly more seasonable.

96


&&

.AVIATION...
(12Z TAFS)
Issued at 623 AM EDT Sat Jul 19 2025

An MVFR deck developed across portions of northern and western
Georgia earlier in the overnight period and has since dropped to
IFR. Expect that these low CIGs will persist at ATL and the other
metro sites until mid-morning. Afternoon Cu will be ~3 kft to ~5
kft. Will be adding a PROB30 for -TSRA in the afternoon/early
evening at ATL, the other metro sites, and CSG. Gusty, erratic
winds may occur with TS. Otherwise, winds will be WSW at 5-10 kts
with gusts up to ~20 kts. May have to contend with development of
low clouds again late tonight/early Sunday morning.

//ATL Confidence...12Z Update...
Medium confidence on coverage of afternoon storms.
High confidence on all other elements.

Martin


&&

.PRELIMINARY POINT TEMPS/POPS...
Athens          94  75  95  76 /  20  10  20   0
Atlanta         93  76  93  76 /  30  20  30  10
Blairsville     85  68  87  69 /  60  30  60  10
Cartersville    90  73  92  74 /  50  20  50  10
Columbus        94  75  95  77 /  20  10  20  10
Gainesville     90  75  93  76 /  40  20  30   0
Macon           96  76  96  77 /  10  10  10   0
Rome            89  73  91  73 /  50  20  50  10
Peachtree City  93  73  93  74 /  30  20  30  10
Vidalia         96  77  98  79 /  10  10  10  10

&&

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

$$

SHORT TERM...Martin
LONG TERM....96
AVIATION...Martin