Johns Creek, Georgia 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

340
FXUS62 KFFC 160757
AFDFFC

Area Forecast Discussion
National Weather Service Peachtree City GA
357 AM EDT Fri May 16 2025


...Morning Area Forecast Discussion...

.SHORT TERM...
(Today through Saturday)
Issued at 355 AM EDT Fri May 16 2025

Key Messages:

 - High temperatures on Friday and Saturday will be well above
   normal across north and central Georgia.

 - Showers and thunderstorms will advance into north Georgia in
   the pre-dawn hours on Saturday. Some of these storms will have
   the potential to become strong to severe.

A 500 mb ridge is extending across the eastern CONUS and will
translate towards the Mid-Atlantic coast throughout the daytime
today. Surface high will meanwhile extend from the northern Gulf
Coast into the Southeast. The warming trend observed over the last
couple of days will continue underneath the ridge and surface high.
After the morning begins with low temperatures in the upper 60s to
low 70s, high temperatures this afternoon will be the warmest of the
week so far. Highs ranging from the upper 80s in far north Georgia
to the mid 90s in central Georgia will range from 8-12 degrees above
daily normals. These high temperatures could furthermore approach
record values in the Atlanta area. While SW flow on the back side of
the high will promote dewpoints in the mid 60s to near 70,
subsidence underneath the high should largely inhibit rain chances
throughout the day today.

An occluded low pressure system over the high plains will slide
eastward towards the Great Lakes this evening into the overnight
hours. A cold front extending from the occlusion over the eastern
Great Lakes will push through Tennessee Valley region late in the
day and into the overnight hours. A line of showers and
thunderstorms is expected to advance into far north Georgia around 3
AM and move southward through the early morning hours. These storms
will move into an environment with lingering SBCAPE between 1500-
2000 J/kg, which will be lower than peak heating but more than
enough to support surface-based convection. 0-1 km shear is
furthermore expected to range from 30-35 kts immediately ahead of
the front. As a result, some thunderstorms embedded within the line
will have the potential to become severe, with damaging wind gusts
being the primary threat. An isolated tornado also cannot be ruled
out, and appears to be most likely in the far northwest corner of
the state where the best instability and shear will overlap.
The SPC has maintained a Day 1 Marginal (level 1 of 5) Risk for
severe weather across far north Georgia, and introduced a Slight
(level 2 of 5) Risk in the extreme northwest portion of the forecast
area to account for these threats.

Instability will continue to decrease as the cold front and line of
storms works its way southward, and the line is anticipated to be
near the I-20 corridor by sunrise on Saturday. During the daytime on
Saturday, the remnant boundary is expected to stall in central
Georgia. By this time, forcing near the front should be weak.
However, with highs forecast to rise into the mid to upper 80s in
north Georgia and low 90s in central Georgia and dewpoints near 70
in areas to the south of the front, SBCAPE values between 2000-3000
J/kg will still allow for the development of isolated to scattered
thunderstorms in the afternoon hours. With deep layer bulk shear of
45-55 kts, some of the storms that develop will have the potential
to become supercellular and produce damaging wind gusts and hail.

King

&&

.LONG TERM...
(Saturday night through Thursday)
Issued at 355 AM EDT Fri May 16 2025

Key Messages:

  - Warm to hot. Highs on many days in long term will be in upper
    80s to lower 90s, depending on cloud cover and other factors.

  - Small chance of severe weather early Saturday morning.
    Conditional threat. Marginal Risk (Level 1 of 5) in place, damaging
    winds primary concern). Diurnal thunderstorms chances most
    afternoons in North Georgia.

The stage is set for a battle of the subtropical ridge and the polar
trough across north Georgia through the long term. A series of short
waves and a stalled frontal boundary will bring several chances of
showers and thunderstorms through the longterm. The first chance for
showers and thunderstorms will be Sunday as a shortwave traverses the
trough to the north. This will help to bring warm moist air up over
the stalled front which will have settled over the southeast. The
exact positioning of the front is still in question, however
scattered showers and thunderstorms are likely across the CWA
(particularly the western counties). CAPE values will be typical for
afternoon conditions in May. Ensemble guidance indicates a 75%
chance of CAPE values greater than 1500 J/kg south of a line
stretching from Lagrange to Macon, though roughly 50% chances remain
up into the ATL metro. At this time wouldn`t be surprised to see
some areas reach closer to 2500 J/Kg by the afternoon.
Unidirectional shear along the stalled frontal boundary may act as a
path for storm motion/organization. While currently unlikely, will
need to keep a close eye on the potential for MCS development.

No significant relief is expected from the shortwave as the
subtropical jet surges northward once again keeping temperatures in
the 80s and even low 90s through the extended period. Diurnal
thunderstorm chances remain across north Georgia where upper level
support remains entrenched. Our next weather pattern change likely
won`t come until near the end of the long term period with a more
substantial trough from the northwest.

SM

&&

.AVIATION...
(06Z TAFS)
Issued at 146 AM EDT Fri May 16 2025

VFR clouds are in place across the majority of north and central
Georgia, with SCT-BKN upper level clouds. Scattered MVFR level
clouds will be possible in the early morning hours around sunrise.
MVFR ceilings are furthermore are forecast to develop in SW GA,
including CSG around 10Z, with IFR level clouds underneath between
11-13Z. A scattered VFR cu field will be in place across the area
underneath upper level clouds on Friday afternoon. Winds will be
SW at 4-7 kts through the morning, increasing to 8-12 kts after
16-17Z.

//ATL Confidence...06Z Update...
Medium confidence on early morning MVFR potential.
High confidence on all other elements.

King

&&

.PRELIMINARY POINT TEMPS/POPS...
Athens          91  70  88  67 /  10  10  20   0
Atlanta         91  71  88  69 /   0  20  30  10
Blairsville     85  63  81  61 /  10  60  30  10
Cartersville    90  68  88  66 /   0  50  30  10
Columbus        92  70  91  69 /   0   0  20  10
Gainesville     89  71  86  68 /   0  30  30  10
Macon           92  69  91  68 /   0   0  20  10
Rome            89  69  87  66 /  10  60  30  10
Peachtree City  91  70  88  66 /   0  10  30  10
Vidalia         94  70  93  71 /   0   0   0  10

&&

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

$$

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