Smyrna, Georgia 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

494
FXUS62 KFFC 191755 AAA
AFDFFC

Area Forecast Discussion...UPDATED
National Weather Service Peachtree City GA
155 PM EDT Mon May 19 2025

...New 18Z Aviation Discussion...

.SHORT TERM...
(Today through Tuesday)
Issued at 329 AM EDT Mon May 19 2025

As the period begins this morning, a 500 mb ridge is extending
from the north central Gulf towards the Great Lakes. The ridge is
also caught between two longwave troughs, one extending from Maine
into the western Atlantic and the other extending from the
Pacific Northwest into the southern Rockies. Georgia positioned to
the immediate east of the ridge axis and underneath northwesterly
flow. Low level flow over the forecast area is light this morning
with a very sparse pressure gradient at the surface. Furthermore,
low temperatures and dewpoints are expected to start the morning
in the upper 60s to low 70s. With the combination of a saturated
airmass, light winds, and lingering soil moisture from yesterday`s
rain, fog and low cloud ceilings are likely to develop during the
early morning hours. Fog may become dense in west Georgia and
portions of Atlanta in the hours around sunrise.

As a disturbance rides the ridge through upper level NW flow over
Tennessee/Kentucky, an associated MCS is currently moving
eastward across north Alabama. This cluster of storms is
anticipated to arrive in far northwest Georgia over the next few
hours. With MUCAPE values of 400-600 J/kg and deep layer bulk
shear between 40-50 kts, it will be possible for the MCS to hold
together and still be capable of producing damaging wind gusts as
it enters the area. Temperatures will be climbing again under the
influence of the ridge, with highs forecast to be in the mid to
upper 80s across north Georgia and the low to mid 90s in central
Georgia. In the peak heating hours, the combination of these
temperatures and dewpoints will lead to heat index values between
95-100 degrees in portions of central Georgia roughly along and
south of a line from Columbus to Macon.

Another round of convection is anticipated to develop well to the
northwest of the forecast area ahead of another disturbance. Hi-
res guidance continues to indicate cold pool organization of this
convection that aligns itself with the northwesterly flow along
the instability gradient on the edge of the ridge. This cluster of
storms could develop into another MCS as it moves southeastward
into the north Georgia in the early afternoon. With increasing
diurnal instability and deep layer bulk shear still between 40-50
kts, thunderstorms this afternoon will be capable of producing
damaging wind gusts and hail. The SPC has introduced a Slight Risk
(level 2 of 5) for severe weather across portions of far north
and northeast Georgia today, with a Marginal Risk (level 1 of 5)
to the immediate south.

By Tuesday, this upper level ridge axis is expected to move to
the east of Georgia. However, the longwave trough to the west of
the ridge will elongate over the Great Plains towards the
Mississippi River Valley region. As this occurs, a surface low
will develop and begin to move eastward. As this occurs, a cold
front will begin to advance towards far north Georgia. In the
meantime, another warm and humid day is expected across the
forecast area, with highs ranging from the upper 80s to low 90s
once again, which will allow for strong diurnal destabilization
ahead of the front. Convection will likely be ongoing through the
day on Tuesday to the north and west, though of lot of what
happens for Georgia will depend on how convection upstream evolves
through the day on Tuesday before arriving in the late
afternoon/evening.

King


&&

.LONG TERM...
(Tuesday night through Sunday)
Issued at 329 AM EDT Mon May 19 2025

Key Messages:

  - Incoming cold front brings severe potential and cooler temps.

  - Mostly dry with low end PoPs across far north GA through the
    end of the long term.

As the fairly robust May trough and associated sfc low traverse
the Ohio Valley, a cold front will swing through the southeast
bringing showers and thunderstorms with it. Confidence has
increased that favorable conditions for severe weather will be in
place ahead of the line as it enters northwest GA, however there
is significant uncertainty in the strength of the cold-front.
Models indicate the potential for a broken/diffuse cold front
resulting in more than one wave of uplift. This means increased
uncertainty in both timing and strength of any storms which may
develop. Current model timing spread sits at around 12 hrs, with
the fastest modes entering the CWA near 18z and the slowest
entering closer to 06Z (well after dark). Overall, timing could be
the difference between storms forming in a region of >2500 J/Kg
CAPE and 370m2/s2 0-3km SRH (Lots of storm juice) or <1000 J/Kg
CAPE and <100m2/s2 0-3km SRH (Not much storm juice). The closer to
peak heating and the more cohesive the cold front the higher the
storm potential. We will definitely need to keep an eye on this
timeframe, especially as more CAMs come into range.

As we move into Wednesday onward, cooler drier air moves into the
southeast behind the cold-front. PWATs drop near or below 1"
through the remainder of the forecast period. High temperatures
fall into the 70s and low 80s with lows in the 50s (could even see
some 40s in the mountains). Temperatures are expected to begin
rebounding through the weekend as riding builds back across the
southern US.

SM


&&

.AVIATION...
(18Z TAFS)
Issued at 143 PM EDT Mon May 19 2025

Ceilings are a mix of MVFR and low-VFR early this afternoon. A
cluster of TSRA currently over southeast TN is tracking ESE/SE
while isolated SHRA have developed over north GA ahead of this
feature. Maintaining PROB30s at ATL, the other metro sites, and
AHN from 19z to 23z for TSRA associated with this activity. VFR
cigs (~15 kft to ~25 kft) are expected overnight into early
tomorrow (Tuesday) morning with the potential for a period of MVFR
cigs and reduced vsby, as has been the case the previous two
days. W to WSW winds today will become light/VRB to calm
overnight, then return to the SW at 8-13 kts with gusts up to ~20
kts tomorrow.

//ATL Confidence...18Z Update...
Medium confidence in timing/coverage of TSRA this afternoon, as
well as evolution of overnight/early morning cigs/vsby. High on
all other elements.

Martin


&&

.PRELIMINARY POINT TEMPS/POPS...
Athens          86  68  90  67 /  30  20  10  50
Atlanta         87  70  90  70 /  20  10  20  70
Blairsville     79  63  84  62 /  40  20  30  90
Cartersville    86  68  90  67 /  30  10  30  90
Columbus        90  68  92  70 /  10   0   0  50
Gainesville     83  68  89  68 /  50  20  20  70
Macon           90  68  92  70 /  10   0   0  30
Rome            86  68  89  67 /  30  10  30  90
Peachtree City  88  68  90  67 /  10   0  10  60
Vidalia         91  71  93  72 /  10   0   0  10

&&

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

$$

SHORT TERM...King
LONG TERM....SM
AVIATION...Martin