Scientific Forecaster Discussion
fxus62 kffc 201932
Area forecast discussion
National Weather Service Peachtree City Georgia
232 PM EST Mon Nov 20 2017
Short term /tonight through Tuesday night/...
with sfc ridge of high pressure pushing quickly off the Carolina
coast and an amplifying upper trough off the southeast Texas coast, the
low level fetch is swinging out of the southeast to SW. As a result, an
area of enhanced low level moisture is progged to advect northward
overnight tonight, therefore most will wake up tomorrow morning to
likely have a mostly cloudy stratocu deck in place. Have also
included some slight pops for light drizzle/rain mention as there
should be at least some isentropic forcing and possible mid/upper
wave influence. Otherwise have held onto some slight to low end
chance pops for light rain mainly to parts of central Georgia late
tomorrow into the overnight given continued possible influence of
any weak perturbation east of the aforementioned southern trough.
Temps stay above the freezing mark tonight given the southerly warm
advection and cloud insolation. Expect mainly warmer afternoon temps
Tuesday for most of central Georgia (generally in the 60s), though
possibly cooler values in the 50s, especially NE Georgia where there
could be a weak hybrid cad wedge holding on with any in-situ
diabatic enhancement from morning clouds/drizzle.
Long term /Wednesday through Monday/...
no major changes to the forecast were needed at this time. An old
frontal boundary will remain situated across central Florida for
much of the period. The next cold front is expected for the latter
half of the weekend.
Quiet weather will be the rule for the extended period. An old
frontal boundary situated across central Florida will be the main weather
maker for the region. Several waves of low pressure/upper
disturbances are progged to move along this old front, but as of
now, both the European model (ecmwf) and GFS are keeping any widespread rainfall well
to the south of the County warning forecast area. The models do keep coming into better
agreement, and overall, only a few tweaks were made to the pops for
the Wednesday night through Thursday night time period. Still, pops
are at most around 30%.
A dry cold front is expected for the late weekend or early next
week. Seasonal to slightly below temps are expected through the
Aviation... 18z update... initial VFR conditions with just some
cirrus skirting across the sites this afternoon, though expecting
a deck of MVFR to possible IFR cigs pushing in from the southeast
after about 04z this evening for the southern sites, then 06-07z
for northern sites. Have broken 1000 ft for now as lowest cigs for
north and slightly lower south, but could warrant lower if future
updates see fit with any higher confidence. Also could have some
areas of drizzle or light rain by tomorrow morning, but chance too
low to include mention for the moment. Winds mainly east-southeast 3-6 kts.
//Atl confidence...18z update...
low to medium on height of morning cigs and light precip chance.
High on all else.
Preliminary point temps/pops...
Athens 39 57 44 62 / 20 20 20 0
Atlanta 44 59 45 60 / 20 20 20 0
Blairsville 36 56 38 56 / 20 20 10 0
Cartersville 38 58 41 57 / 10 20 10 0
Columbus 47 65 49 65 / 10 20 20 5
Gainesville 39 55 44 60 / 20 20 20 0
Macon 45 65 47 65 / 10 20 20 5
Rome 37 60 40 57 / 10 10 10 0
Peachtree City 38 61 44 61 / 20 20 20 0
Vidalia 47 68 52 67 / 5 40 40 10