Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Peachtree City Georgia
407 am EDT Sat Aug 2 2014
Short term /today through Sunday/...
Upper trough remains the dominate feature for the short term and is
expected to weaken some and drift east through Sunday. Moist SW
flow ahead of the upper trough the main reason for shower and
thunderstorm chances through the period. Weak short wave in the flow
looks to enhance some shower activity this morning. Then mainly weak
instability will help enhance shower and some thunderstorm activity
for the afternoon into the evening. Pinning down when the best
chances for showers and storms is a low confidence forecast but any
time between later morning and this afternoon seems reasonable.
With the upper trough weakening and drifting east...central Georgia seems
to be the best area for precipitation chances on Sunday with the best
instability forecast over central Georgia.
Cooler low level east flow still in place for today and Sunday and
is making the high temperature forecast very difficult.
Forecast high temperatures running around 10 degrees below normal
today and 4-8 degrees below normal for Sunday.
Forecast low temperatures running slightly below normal tonight.
Overall confidence is low.
Long term /Sunday night through Friday/...
The year of the Summer cold front continues for at least the first
part of the long term as persistent East Coast longwave trough
allows for a weak front to push into north Georgia. This will be
mainly marked by a decrease in moisture as has been the case with
several fronts already the past few weeks. Deep layer moisture
will drop for north Georgia as well on Monday with only slight
chance probability of precipitation required and this too may prove to be too much given
meager forcing and moisture profile. To the south...a much
different story as aforementioned trough and embedded shortwaves
continues likely probability of precipitation in areas of adequate moisture which looks to
be from Columbus to Macon and points southward for Monday.
Main change in the extended will be the exodus of the upper trough
eventually by middle week off the East Coast and the local area
replaced by Bermuda ridge axis up to 700mb and a non distinct
pattern from 500mb on up. This along with moisture returning to
near normal levels screams for our typical low end scattered
thunderstorm activity and will advertise such in new extended.
main concern is developing IFR-MVFR ceilings with improvement
expected during the day to VFR. Potential for early morning shower
activity with maybe some MVFR visibility restrictions in showers and
possibly fog. Potential for mainly afternoon thunderstorms with
the lowest chances around atl and ahn.
//Atl confidence...06z update...
low confidence on ceilings...visibilities and weather.
High confidence on wind.
Preliminary point temps/pops...
Athens 81 68 86 69 / 60 20 30 20
Atlanta 81 68 85 71 / 50 20 30 20
Blairsville 79 59 82 65 / 50 20 30 20
Cartersville 82 65 87 67 / 50 20 30 20
Columbus 83 71 86 72 / 60 50 40 30
Gainesville 79 66 84 69 / 50 20 30 20
Macon 82 69 85 70 / 70 50 50 40
Rome 83 66 87 68 / 40 20 30 20
Peachtree City 82 67 86 68 / 60 30 30 20
Vidalia 88 72 87 73 / 60 50 60 60