Area Forecast Discussion
Issued by NWS Atlanta, GA
FXUS62 KFFC 290208
Area Forecast Discussion
National Weather Service Peachtree City GA
1008 PM EDT THU JUL 28 2016
Have adjusted POPs and temps tonight as needed. A few isolated
showers remain across the state...but anticipate they will
diminish in the next few hrs. Wind gusts have died down and temps
are expected to drop into the lower-mid 70s tonight.
Latest WV imagery showing two mid/upper level high centers... one
across the Great Basin and the other SE of the Carolina Coast.
Between these features is a deepening trough with embedded
impulses. The weak impulse stretching from Central TN to N AL has
been responsible for the increase in cloud cover and shower/storm
activity today across N Ga. This disturbance will deamplify
overnight and allow for a decrease in precip coverage...however
its remants will keep cloud cover across the northern CWA. By
daybreak Fri expect a decent blanket of lower level cloud cover
across most of N Ga before burning off by about 15z. High temps
will range from upper 80s north to upper 90s south. With troughing
in place and a weak SW flow...diabatic heating and ample Gulf
moisture will lead to a chance of showers and storms Fri afternoon
and evening...mainly across north Ga where closer proximity to
minor mid level impulses within broad troughing and orographic
effects can act in concert within high theta-e air. Trailing vort
lobe from today`s disturbance currently across MS/LA could track
east and spark convection across AL/west Ga as well. Will have to
With sufficent CAPE and mid level flow near 20-25kts...a few
storms on Fri could be strong with downburst wind and heavy rain
the primary threats. Organized severe weather not likely.
.PREV DISCUSSION... /Issued 748 PM EDT THU JUL 28 2016/
PREV DISCUSSION... /Issued 340 PM EDT THU JUL 28 2016/
SHORT TERM /Tonight through Friday Night/...
Still no major changes in the short term with the over
all atmospheric pattern. There are a few more showers developing
across the area than the past few days but that should help to keep
the temperatures down a bit through the rest of the afternoon and
evening. The main east-west oriented upper ridge continues to
control the weather pattern across the southeastern states. The wave
that was over MS and AL yesterday is still there but this is what is
now pushing the showers and isolated thunderstorms into our area.
Right now we are only seeing showers mainly over AL but the
thunderstorms over northern AL are knocking on the Georgia
border...and should push into the state over the next few hours.
With the increased gulf moisture moving into the region coverage
may be a bit more Friday than today especially across northern GA.
Temps should continue slightly above normal with Heat Index values
remaining below 105 so no advisory expected.
LONG TERM /Saturday through Thursday/...
Primary concern in the long term period is increasing chance for
diurnal convection compared with last few days. While overall
pattern of zonal flow along northern CONUS (latitudes north of
40deg N) and ridging further south will persist, broad troughing
to persist and deepen a little over midwest states through this
weekend before upper ridging over the central US builds north and
east next week. With weak southwest flow aloft across the
southeast ahead of broad troughing to the north, should see
increased moisture and increased convection, both in coverage and
intensity, as a result. No one day to focus on for heavier
rainfall or more widespread convection. Guidance blend of 30-50pct
PoP looks good for most afternoon and evenings, but particularly
on Sun thru Tues.
Fortunately, with more clouds and precip, temps will drop closer
to seasonal norms or just above instead of more recent streak of
near or above 100F in parts of CWA. Unless we get a lot of rain,
temps may creep back up to these levels by middle of next week
Another concern, though not a direct threat at this time, is more
active tropical development in the Atlantic basin. Last few
deterministic GFS/ECMWF runs have become consistent in developing
a weak tropical low/wave that moves into Caribbean and possibly
south FL early next week. GGEM even more aggressive with tropical
development both in south Atlantic and in Caribbean Sea. Of
course can`t pin down anything specific yet. Just pointing out
that Atlantic basin becoming more active and needs to be watched
Scattered showers persist this evening across Ga. Expect these to
linger mainly around the northern TAF sites. Have TEMPO SHRA
going for metro sites thru 03z. Expect cloud cover to linger
across N Ga overnight and MVFR ceilings (BKN015) seem probable
over northern sites (metro and AHN) from about 10z-13z Fri.
Expect this cloud cover to burn off and be left with normal cu
deck around 4-5kft late morning/early afternoon with showers and
possibly a few thunderstorms developing by 17/18z...mainly across
north Ga once again.
//ATL Confidence...00Z Update...
Medium on all elements
.PRELIMINARY POINT TEMPS/POPS...
Athens 74 92 74 94 / 20 20 20 30
Atlanta 74 89 74 91 / 30 30 20 40
Blairsville 69 84 68 85 / 40 40 30 50
Cartersville 73 88 72 91 / 40 30 20 50
Columbus 75 94 75 95 / 20 20 20 30
Gainesville 73 88 73 91 / 40 30 20 40
Macon 75 95 74 96 / 5 10 20 30
Rome 72 89 71 91 / 40 30 20 50
Peachtree City 73 90 73 92 / 30 20 20 40
Vidalia 76 98 76 97 / 5 10 20 30