881 
FXUS62 KFFC 081133 AAA
AFDFFC

Area Forecast Discussion...UPDATED
National Weather Service Peachtree City GA
733 AM EDT Sat May 8 2021



...12Z Aviation Area Forecast Discussion...

.PREV DISCUSSION... /Issued 440 AM EDT Sat May 8 2021/ 

SHORT TERM /Today through Sunday/...

No significant forecast concerns in the short term period. 

Only high and mid clouds expected in the first 12h of the 
forecast as warm advection in mid levels leads to vertical ascent 
and clouds/light precip in northwest flow over the TN/OH valleys. 
These clouds expected to stream SE into the state. Could even see 
some sprinkles or light rain sufficient to measure more than a 
trace this afternoon before weak subsidence and clearing 
downstream of next weak wave on Sunday. This wave developing in 
zonal flow to the west over the OK, MO, and other central MS 
valley states will move east towards the area after Sunday. So 
other than a few sprinkles in the far NW today, a dry forecast 
with only high clouds and light west winds. 

SNELSON

LONG TERM /Sunday Night through Friday/...

As the extended period begins on Monday night, a nearly zonal upper 
level flow regime will be in place across much of the region. At the 
lower levels, southwesterly flow and advection of warm and moist air 
will be ongoing, leading to dewpoints in the mid 60s across north 
and central Georgia. Meanwhile, an upper level shortwave and an 
associated surface low will be passing eastward through the 
Tennessee Valley region towards the mid-Atlantic Coast during the 
overnight hours. Showers and thunderstorms will enter northwest 
Georgia Sunday night ahead of a cold front extending southward from 
the surface low, and will spread southeastward through the day 
Monday as the front approaches. PoPs are expected to become likely 
to categorical across north and central Georgia by Monday afternoon. 
Instability will be sufficient to support at least scattered 
thunderstorms, with the best coverage anticipated during the 
afternoon hours with peak daytime heating. With the deep moisture in 
place, combined with deep layer bulk shear values of 35-45 kts ahead 
of the front, modestly steepened mid-level lapse rates of 6.5-7 
J/kg, there is a chance that some isolated storms could become 
strong to severe on Monday.

The cold front is anticipated to clear the forecast area to the 
south by Tuesday morning before stalling across the Florida 
Panhandle through mid-week. Some model inconsistency remains with 
respect to the southward propagation of the front before it stalls, 
but confidence continues to increase. A disturbance traversing the 
upper level flow on Tuesday provide a focus for showers and isolated 
thunderstorms during the day on Tuesday. The highest chances at this 
time appear to be across the far southern tier, in closest proximity 
to the frontal boundary and also where deeper moisture is expected 
to linger. PoPs will be a bit lower to the north where relatively 
drier low level air is forecast.

A deep upper trough over the Rockies on Tuesday will move eastward 
towards the Great Lakes region through mid-week. Coverage of showers 
and thunderstorms is expected to persist as a cold front associated 
with this trough approaches the region, primarily on Wednesday and 
Thursday. The best moisture and instability is forecast to remain 
south of the forecast area in the vicinity of the stationary front 
lingering across the Florida Panhandle. This should serve to limit 
the threat of heavy rain and severe weather, but will need to be 
monitored. The axis of the trough and the cold front are expected to 
clear Georgia Thursday night into Friday morning, which will lead to 
a drier airmass setting up over the area towards the end of next 
week.

King

FIRE WEATHER...

Humidity will likely drop below 20 percent this afternoon over 
middle GA. Recent local research has shown strong tendency for model 
overforecasting of surface moisture in this pattern so have 
compensated official forecast with increased weight of NBM 10th 
percentile dewpoints. The resulting sub-25 percent min RH field 
includes most areas parallel and about 50 miles south of the fall 
line. Thankfully, winds will be light from the west at 5-10 mph in 
this area. Still enough for fire danger criteria with dry fuels.

&&

.AVIATION...
12Z Update...
VFR conditions thru 18Z Sun. High and mid clouds today with cigs
down to 8-10kft possible at times before clearing after 00Z Sun.  
Sfc winds will be W 5-10kts today decreasing to calm to very light
S winds after 01Z Sun then SSW 7-12kts with gusts to 20kts after 
14Z Sun. 

//ATL Confidence...12Z Update...
High confidence on all elements.


SNELSON

&&

.PRELIMINARY POINT TEMPS/POPS...
Athens          75  53  83  63 /   5   5   0  30 
Atlanta         75  56  83  65 /   5   5   0  40 
Blairsville     67  49  77  58 /   5   5  10  60 
Cartersville    74  53  83  61 /   5   5   5  60 
Columbus        80  54  88  65 /   5   0   0  30 
Gainesville     72  52  82  63 /   5   5   5  40 
Macon           80  52  89  63 /   5   0   0  20 
Rome            74  53  83  62 /  10   5  10  60 
Peachtree City  77  54  85  63 /   5   5   0  40 
Vidalia         81  57  89  66 /   0   0   0   5 

&&

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

$$

SHORT TERM...SNELSON
LONG TERM....King
AVIATION...SNELSON