Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Peachtree City Georgia
415 am EDT sun Aug 31 2014
Short term /today through Monday/...
wave of persistent convection should continue to propagate eastward
and diminish in coverage early this morning. Lingering low level
moisture from the overnight precipitation will likely allow for patchy fog
this morning across the County Warning Area.
Models in decent agreement with continued weakening of shortwave
energy north of the area and further elongation of the enhanced
moisture field today. Still enough moisture and instability prognosticated
to keep chance probability of precipitation in the far north and southeast with slight
elsewhere. Hi-res solutions verified decently on recent convective
coverage /albeit timing discrepancies/ and have trended Sunday probability of precipitation
close to this. Overall looking to be less coverage today and best
chance for some strong to isolated severe development will be south
and east of Macon...based on near 1500-2000 j/kg of ml-SBCAPE with a
bit higher dcape. Still pretty decent precipitable waters based on recent bufr
soundings as well. Main threats therefore look to be strong
downburst winds and frequent lightning with brief heavy rainfall.
Weak surface ridge lingering across the southeast Continental U.S. Through Monday
but enough moisture to support general chance probability of precipitation for diurnally
driven convection. Too difficult at the moment to favor a particular
portion of the County Warning Area much more than another for development.
For temperatures...general guidance blend results in near normal values
today then slight increase to above normal for Monday.
Long term /Monday night through Saturday/...
high pressure aloft and at the surface will continue over much of
area for the extended portion of the forecast. A weak Lee trough
will be situated across northeast Georgia through the first half of the
week. A slightly stronger front may impact the forecast area by next
Diurnal convection expected for much of the week. Models are
progging a weak surface boundary to drop down across north Georgia by
mid-week. Convection doesn't seem to be enhanced along this feature
for now. Have not made many changes to the forecast...persistence is
the rule with isolated/scattered probability of precipitation each afternoon and evening.
By the end of the week/early weekend...high pressure aloft begins to
retrograde west. The surface high will begin to push offshore as a
front approaches from the west.
Temperatures will remain above normal through the period.
mainly VFR ceilings with potential for MVFR visibilities or even scattered to broken
MVFR ceilings in 10-14z period this morning as showers/storms continue
to push east of kahn and kmcn. Winds generally vrb to calm early
this morning then SW Sunday at 7 kts or less. Cumulus field Sunday in
5-6 kft range but may only get to broken in southern sites. Chance
for precipitation too low to include in taf for Sunday afternoon other
than prob30 for kmcn.
//Atl confidence...06z update...
low to medium on MVFR cigs/vsbys.
Medium on Sunday precipitation chances.
High all else.
Preliminary point temps/pops...
Athens 93 70 95 74 / 20 20 30 10
Atlanta 90 73 92 77 / 20 10 30 10
Blairsville 85 64 87 70 / 40 30 30 10
Cartersville 90 69 92 74 / 30 20 30 10
Columbus 93 74 94 78 / 20 20 30 10
Gainesville 89 71 91 76 / 30 20 30 10
Macon 93 71 95 75 / 30 20 30 10
Rome 90 68 93 74 / 30 30 40 10
Peachtree City 91 69 92 73 / 20 10 30 10
Vidalia 95 74 94 75 / 30 30 30 30