Area Forecast Discussion
Issued by NWS Atlanta, GA
FXUS62 KFFC 301418
Area Forecast Discussion
National Weather Service Peachtree City GA
1018 AM EDT TUE AUG 30 2016
Deep easterly will continue across the CWFA today. Latest visible
satellite imagery shows clouds beginning to spread from east to
west across central GA. A few showers are also noted across the
far SE CWFA. Hi-res models still only show isolated to scattered
activity across that region today. This seems reasonable. There
were no major changes to the ongoing forecast...just made some
tweaks to the sky/hourly temp grids.
.PREV DISCUSSION... /Issued 740 AM EDT TUE AUG 30 2016/
SHORT TERM /Today through Wednesday/...
Gulf of Mexico tropical system has little if any effect on the
forecast area through the short term forecast period. Main influence
over this region will be the weak upper circulation meandering over
the Georgia/Carolina coastal plains. For today it appears that main
chances for precipitation will once again be across our central
Georgia counties where better moisture and closer proximity to the
upper low remain. Should see a diurnal maximum of scattered
convection diminishing overnight. Wednesday is a bit trickier with
weak cold front approaching the northern border potentially
increasing the chances for some isolated to scattered convection
across the north and the uncertainty of the path and speed of the
gulf system and any influence it may exert across the southern
reaches of the forecast area. Should remain far enough away to have
little impact through the day Wednesday with isolated to
scattered...mainly diurnal...convection expected once again.
LONG TERM /Wednesday Night through Monday/...
The long term period begins with the area under a squeeze play
from the approaching front to the north and the tropical system
approaching the Florida coast during this same timeframe. this
leaves the local area under relatively benign conditions
initially with a slot of dry mid level air characterized by PWATS
around 1.5 inches. Likewise CAPE values remain below climo norms
and corresponds to a low pop forecast through Thu morning.
After a rough patch in forecasting the gulf low this past
week...the models have now come into excellent agreement the last
24 to 36 hours both with each other and run to run. Latest
iterations follow NHC official forecast nicely with a North
FL...SE Georgia main impact and precip axis just getting into our
SE counties. Much of this will depend on eventual size and
strength of the storm system but for now have gone likely pops for
Thu for SE tier or two of counties.
Meanwhile...a frontal boundary moves in from the North and is
accompanies by some enhanced mid level moisture and slight cooling
aloft. Still though...CAPE values looks to barely make 1000 J/KG
and overall profile within the front suggests capping at mid range
chance for now for the northern most counties.
If GFS is correct...could very well be one of the nicest Labor Day
weekends we have seen here in awhile. Low temps through early next
week reach the upper 50s for most of North GA and although highs
are seasonal...drier air would make conditions feel much different
than the summertime conditions we are currently under. ECMWF
continues to leave some moisture behind and overall is not
aggressive with the front. As a compromise...have raised
overnight lows some 2 to 3 degrees for now until some better
agreement is reached.
VFR conditions are expected to predominate across the forecast
area through the majority of this forecast period. Will see some
local MVFR or lower visibilities developing through 14Z...mainly in
traditionally fog-prone areas. Also seeing some MVFR or lower cigs
developing across the Georgia/South Carolina coastal plain that
could spread into far eastern and southern portions of the forecast
area...however I do not expect any impacts at the TAF sites at this
time. Isolated to scattered convection is likely again this
afternoon and evening...generally between 18Z and 02Z. Best chances
will remain south and east of the TAF sites. Right now I believe
chances are too low at all of the TAF sites except KMCN to include
in this forecast. Winds will remain easterly...3-7KT through 14Z
then increasing to 7-12kt after.
//ATL Confidence...12Z Update...
High on all elements.
.PRELIMINARY POINT TEMPS/POPS...
Athens 91 71 91 72 / 20 10 20 20
Atlanta 91 74 91 73 / 20 10 20 20
Blairsville 89 66 87 66 / 10 10 30 10
Cartersville 93 70 92 70 / 10 10 20 10
Columbus 93 74 93 74 / 20 20 20 20
Gainesville 90 73 89 72 / 10 10 20 20
Macon 93 72 91 72 / 30 20 30 20
Rome 92 69 93 71 / 10 10 20 10
Peachtree City 91 70 91 70 / 20 10 20 20
Vidalia 94 74 89 73 / 40 40 40 30