Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Peachtree City Georgia
144 PM EDT Tuesday Sep 30 2014
Previous discussion... /issued 1144 am EDT Tuesday Sep 30 2014/
Update...made some minor modifications to sky grids as clouds
hanging on a little longer...especially over central Georgia.
Otherwise...grids in excellent shape and no changes planned.
Previous discussion... /issued 725 am EDT Tuesday Sep 30 2014/
Previous discussion... /issued 332 am EDT Tuesday Sep 30 2014/
Short term /today through Wednesday/...
except for low clouds out there this morning...expecting a pretty
quiet short term forecast. Shortwave axis has pushed east and with
it most of the rain...though some patchy drizzle remains and will
likely continue off and on for a few hours with low level moisture
basically confined below 750mb and drying from the top-down through
sunrise. May see some areas of dense fog as well especially over the
next few hours.
Upper flow flattens somewhat today and tonight as the higher
amplitude pattern remains to the north...leaving US in just some
weak ridging aloft and surface high pressure dominating the area...
with very little in the way of surface flow. Expect clouds to clear
quickly this morning leaving US with a pretty nice day. With pretty
much neutral advection in place...highs today should actually be a
tad warmer than seasonal averages with the slowly increasing
thicknesses. Will definitely notice a difference in lows tonight...
especially across north Georgia and outlying areas...just because
lack of clouds and lower dewpoints will allow temperatures to cool
more than the past few days. Another round of fog likely tonight
with surface winds nearly calm everywhere. An even warmer day
expected tomorrow as weak ridging continues in advance of the next
longwave system...to impact US during the extended. Generally took a
consensus blend for temperatures through the short term.
Long term /Wednesday night through Monday/...
a cold front is expected to impact the County warning forecast area by the late week.
High pressure begins to shift offshore Wednesday night in advance of
an approaching cold front. The front should begin to cross the
Mississippi River by very early Friday morning and approach the northwest
corner of the County warning forecast area by midday Friday. Scattered thunderstorms are
expected along and ahead of the front. Since the main middle level
forcing gets shunted well north of the County warning forecast area...will keep out the
mention of severe at this time. However...since the front will be
coming through the area during peak heating and there will be some
good surface instability...do think a few of the storms could be
strong. The front should clear the County warning forecast area by early Saturday morning.
High pressure will build for the latter half of the weekend into the
early part of next week. Accompanying the high pressure will be
cooler temperatures and a drier airmass. Models have been consistent in
progging middle 50s across much of the County warning forecast area for lows Sunday
The cooler temperatures should not last too long. Return flow off of the
Gulf will bring increasing moisture and temperatures ahead of the next cold
front expected by the middle of the week.
stratus which has plagued the northern terminals the last several
days has finally lifted with a scattered deck prevailing for atl and
surrounding sites. Mcn and csg continue to have some low ceilings but
are rising with MVFR conditions now realized. Models show very low
level moisture coming in tonight which would be more indicative of
fog than low clouds. Not ready to jump on board all the way just
yet but will indicate some reduced visibility with greatest reductions
over ahn and southern terminals. Any fog that does develop should
burn off quickly on Wednesday with VFR conditions prevailing for the
remainder of the taf period.
//Atl confidence...18z update...
medium on reduced visibility potential.
High on remaining elements.
Preliminary point temps/pops...
Athens 80 61 85 63 / 5 5 5 10
Atlanta 80 64 84 65 / 5 5 5 5
Blairsville 78 54 81 58 / 5 5 5 10
Cartersville 82 57 85 63 / 5 5 5 10
Columbus 83 66 86 68 / 5 5 5 10
Gainesville 79 62 83 62 / 5 5 5 10
Macon 81 61 86 65 / 5 5 5 5
Rome 83 58 86 61 / 5 5 5 0
Peachtree City 81 58 84 63 / 5 5 5 10
Vidalia 81 64 86 66 / 5 5 5 10