785 
FXUS62 KFFC 101933
AFDFFC

Area Forecast Discussion
National Weather Service Peachtree City GA
333 PM EDT Sat Jul 10 2021


.SHORT TERM /Tonight through Sunday Night/...

Northwesterly upper level flow continues across north and central 
Georgia behind a 500 mb trough positioned near the Mid-Atlantic 
coast. However, a transition in the flow aloft is anticipated 
tonight as as the trough over the mid-Atlantic flattens out and 
another trough to the northwest digs southward into the midwestern 
CONUS. Southwesterly flow upper level flow is thus expected to set 
up by Sunday and remain through the remainder of the weekend. At the 
surface, a stationary front is stalled north of the forecast area. 
As the upper trough moves into the midwest and develops into a 
closed low, the stationary front will lift to the north and a cold 
front extending from the low will move eastward towards the 
Mississippi Valley region. Meanwhile, the Bermuda high will begin to 
shift westward towards the Mid-Atlantic coast through the remainder 
of the weekend, allowing the low-level flow to take on a more 
southerly component. This synoptic setup will allow for increased 
moisture advection from the Gulf of Mexico over much of the region, 
with dewpoints forecast to reach as high as the mid 70s and 
precipitable water values anticipated to increase to 1.75-2 inches.

Scattered showers and thunderstorms are ongoing across roughly the 
eastern half of the forecast area as a weak upper disturbance 
traverses the upper level flow. Isolated, diurnally driven 
convection has also begun to redevelop over west Georgia. As a 
result, high-end chance PoPs are expected to persist through the 
remainder of the afternoon before diminishing after sunset. Hi-res 
model guidance is inconsistent in handling convective development on 
Sunday. However, considering the increasing moisture, scattered to 
numerous showers and thunderstorms are forecast during the peak 
heating hours tomorrow across the area,

SBCAPE values this afternoon will be as low as 1500 J/kg in west-
central Georgia and as high as 3500 J/kg in east-central Georgia, 
Ample destabilization is expected across the area Sunday, as well. 
With the stationary frontal boundary positioned well to the north of 
the forecast area, there will be little shear to speak of this 
afternoon and tomorrow. Mid-level lapse rates are also expected to 
remain marginal, at mainly less than 6.0 C/km. As a result, an 
organized threat for severe weather is not anticipated today, 
although isolated storms may become strong to severe. Stronger 
storms will be capable of producing gusty winds frequent lightning. 
Furthermore, with high PWATs and weak boundary layer flow, slow-
moving stronger storms will likely produce heavy rainfall and a 
potential for localized flooding.

Considering the ample atmospheric moisture, afternoon highs are 
expected to be mainly 1-4 degrees below climatological normals, 
ranging from the mid 80s to low 90s, and morning lows are expected 
to be 2-5 degrees above climatological normals, ranging from the 
upper 60s to mid 70s.

King


.LONG TERM /Monday through Saturday/...

Typical Georgia summertime weather expected with remarkable 
consistency over the long term period and beyond with afternoon 
highs in the mid 80s to low 90s, overnight low temps and dewpoints 
hovering around 70 degrees, PWATS steadily between 1.5-2", and a 
roughly 50-70% chance of afternoon diurnal showers and thunderstorms 
at any given location. 

Synoptically, the Bermuda High over the western Atlantic will remain 
steadfast, with an upper-level low over the Ozarks stalling and 
quickly occluding and shifting northward at the start of next week, 
taking any hope of an airmass change with it. The broad fetch of low-
level southerly moisture will fuel diurnal showers and storms each 
afternoon. With so much moisture throughout the vertical profile and 
minimal upper-level support/dynamics, overall severe thunderstorm 
chances will be low outside of some anomalous water-loaded 
downbursts in isolated locations. Rather the main concern should be 
training or slow moving storms producing 2-3" of rain in isolated 
locations leading to localized nuisance flooding.

Thiem

&&


AVIATION...
18Z Update...
Scattered convection has developed and is expected to persist 
through the afternoon and evening, diminishing after sunset. As a 
result, VCSH will run until 00Z while a TEMPO group for TSRA extends 
over the most likely time window, from 18-21Z. Primarily VFR 
conditions are in place across north and central Georgia, with BKN 
ceilings between 035-050, which should persist through the afternoon 
before scattering by 00Z. Scattered MVFR level clouds are possible 
on Sunday morning after 12-13Z. Winds will be W through the 
afternoon at 6-10 kts shifting to SW at 3-6 kts overnight, with the 
exception of gusts associated with any SHRA/TSRA.

//ATL Confidence...18Z Update...
Medium to high confidence on all elements.

King

&&

.PRELIMINARY POINT TEMPS/POPS...
Athens          71  88  70  89 /  30  60  50  60 
Atlanta         71  86  71  87 /  30  60  40  70 
Blairsville     65  82  66  81 /  40  70  60  80 
Cartersville    70  87  70  87 /  30  60  50  70 
Columbus        72  89  72  90 /  30  50  40  70 
Gainesville     70  86  70  87 /  30  70  50  70 
Macon           71  90  71  91 /  30  60  40  60 
Rome            71  87  71  86 /  40  60  50  80 
Peachtree City  70  86  70  87 /  30  60  40  60 
Vidalia         73  89  72  89 /  30  60  40  60 

&&

.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...King
LONG TERM....Thiem
AVIATION...King