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National Weather Service Peachtree City GA
145 PM EDT SAT JUL 23 2016

.SHORT TERM /Tonight through Sunday Night/...
The morning sounding showed ample deep layer moisture and moderate
instability... with 1.7 pws and around 2500-3000 J/KG of afternoon
cape. This coupled with a weak upper disturbance settling over
north GA has resulted in scattered to numerous showers and
thunderstorms already developing across most of north GA. Although
this convection will be strong at times... no expecting much
severe storm threat as some warm air in the upper mid levels
should help hold most convection down just below severe limits
this afternoon and evening... with the main threats being wind
gusts in the 35-45 mph range... very heavy rain due to slow moving
storms and cloud to ground lightning. These storms should
gradually dissipate through mid to late evening with loss of
daytime heating... and although cannot rule out an isolated
shower or storm overnight... will likely show NIL pops after
midnight. Models show the upper disturbance currently over MS-AL-
GA drifting further west on Sunday while another disturbance
southeast of the GA coast drifts west across south GA on Sunday.
This suggest the greater convective threat on Sunday will be west
and south of the forecast area. However... with ample moisture and
moderate instabilities still in place... will continue to show at
least a 30 percent chance of afternoon and evening storms on
Sunday...but severe storms are not expected at this time.  

Otherwise... see no major changes in temperatures with lows mainly
in the 70s and highs in the 90s. Heat Index values of 99 to 103
degrees are expected on Sunday... so no heat advisory is
anticipated at this time.

39


.LONG TERM /Monday through Saturday/...
No major changes were made to the extended periods. The previous
discussion follows. 20

Previous Long Term.../Issued at 315 AM EDT SAT JUL 23 2016/

LONG TERM /Sunday Night through Friday/...
The long term starts off with an upper level ridge across the
southern Appalachians and an easterly wave moving across FL. The
GFS has this wave affecting central GA more than the NAM or
European models. At this time think convection will be highly
diurnal Sunday evening.

The upper level ridge pattern continues for Monday with mainly 
afternoon showers and storms. Most high temperatures will again
be in the 90s except upper 80s for portions of the mountains.

The upper ridge moves over the area for Tuesday and Wednesday but
slightly weaker and continues to slightly drift S Thursday into 
Friday. This should continue the pattern of mainly Diurnal showers
and storms across the area...favoring the mountains and portions of 
W GA. Highs in the 90s will continue for most areas and slightly
cooler in the mountains.

BDL

&&

.AVIATION...
18Z Update...
Area radars show numerous showers and thunderstorms across much of
north GA... and some of these storms should sag south and traverse
the Atlanta and Athens TAF sites through the afternoon. More
isolated coverage is expected around CSG and MCN later this
afternoon. Convection will greatly diminish by 02-03z Sun. Expect
low scattered coverage Sunday afternoon... warranting a prob30
tsra for all taf sites around 19-22z Sun. Winds will be light from
the west...southwest around 6-7kts or less through the forecast.

//ATL Confidence...
18Z Update...

Medium on convection timing and coverage on Sunday. 
High on remaining elements.

39

&&

.PRELIMINARY POINT TEMPS/POPS...
Athens          74  97  74  95 /  40  30  20  40 
Atlanta         75  94  75  93 /  40  30  20  40 
Blairsville     68  90  68  89 /  40  50  20  50 
Cartersville    73  95  73  93 /  40  40  20  50 
Columbus        75  96  75  95 /  30  30  20  40 
Gainesville     74  94  74  93 /  40  40  20  50 
Macon           74  97  74  95 /  30  30  20  40 
Rome            73  96  73  94 /  40  40  20  50 
Peachtree City  73  95  72  93 /  40  30  20  40 
Vidalia         75  97  74  95 /  30  30  20  30 

&&

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

$$

SHORT TERM...39
LONG TERM....20
AVIATION...39

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