Area Forecast Discussion
Issued by NWS Atlanta, GA

Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

FXUS62 KFFC 022359

Area Forecast Discussion
National Weather Service Peachtree City GA
659 PM EST Wed Dec 2 2020



.PREV DISCUSSION... /Issued 233 PM EST Wed Dec 2 2020/

..Afternoon Area Forecast Discussion for Dec 2...

SHORT TERM /Tonight through Thursday Night/...

The quiet weather pattern will continue through tomorrow. Surface
high and weak upper level ridging will keep dry conditions across
the area with mostly clear skies. With winds diminishing to light
and variable overnight we will once again see some radiational
cooling set up with lows near freezing across much of the area and
25-30 degrees in the higher elevations. Afternoon highs will
climb to near normal with temperatures in the 50s to lower 60s
tomorrow. As the surface high shifts of the SE coast tomorrow
evening, models are in good agreement developing a weak surface
low along a weak upper level wave along the Florida panhandle. Am
not as confident in the increased moisture across the area
afternoon and overnight with mostly southeast winds across the
area. Have taken a slower progression of showers as the weak
surface boundary shifts close to our area by Friday morning. With
increased clouds during the overnight hours, the morning lows on
Friday will be closer to normals for this time of year with lows
in the upper 30s to lower 40s.


LONG TERM /Friday through Wednesday/...

Long term picks up on Friday with the next rain maker moving
through the CWA. Lobe of tropopause PV that was previously cut off
over OK and TX will eject into the area reflecting on the 500 mb as
a strong shortwave that will phase with a larger trough over the
eastern US. Surface low develops along left jet exit region and
skirts just to the north of the CWA during the afternoon. There
will be more than enough moisture available for decent warm
sector rainfall out ahead of the cold front associated with the
system. Models are in decent agreement on the placement of
rainfall, but less so on amounts. Will lean towards the NAM and
more hi-res guidance which is showing about an inch over N GA with
at least a half an inch across most of the CWA. Some models do
hint at some enhancement across central GA in a band, but will
leave the details of that to the short term. NAM and Euro are a
little faster than some of the other guidance in bringing the
system across the area, with the bulk coming in during the day on
Friday compared to late evening on some of the others. Will lean
towards the faster guidance on this package, but will still keep
some PoPs around overnight for the possibility of the slower GFS.

Instability looks to be minimal, though some may exist in a thin
band just ahead of the cold front into central GA. Surface temps
look to only be into the upper 50s to 60s below a weak inversion
per model soundings, so will be tough to get any surface based
storms which would make the impressive looking SRH values less
useful. Not expecting much in the way of severe weather right now,
though a thunderstorm certainly can`t be ruled out across central

System moves away from the area by Saturday. Euro and GFS have
differences on how they handle a series of shortwaves rounding the
larger east coast trough as well as how quickly another PV
anomaly within the southern stream is absorbed and phased into
that trough Sunday into Monday. The current GFS solution could
bring the opportunity for some light rain to far central GA on
Sunday and then the possibility of some very light snow in the
higher elevations of the Appalachians on Monday, though this would
be not be as substantial as our event this past Monday. The Euro
solution keeps the shortwaves further to the west, preventing any
precipitation in this time period. Given large uncertainty both
between models and run to run for the same models, not inclined to
add any PoPs at this time for Sunday/Monday.


00Z Update...
A few high clouds are possible tonight. A wind shift from NE to NW
will take place around 06Z although winds will be light at 4 kts or
less. An approaching system will begin to gradually decrease
ceilings around 01Z on Friday for the ATL metro area but all sites
stay in VFR for the TAF time period.

//ATL Confidence...00Z Update...
High confidence on all elements.



Athens          30  57  41  59 /   0   0  10  60
Atlanta         30  55  43  58 /   0   0   5  60
Blairsville     28  53  38  51 /   0   0  20  70
Cartersville    27  55  42  57 /   0   5  10  60
Columbus        31  59  46  64 /   0   0  10  60
Gainesville     32  55  41  54 /   0   0  10  60
Macon           28  60  44  66 /   0   0   5  60
Rome            25  56  42  57 /   0   5  20  60
Peachtree City  27  56  42  60 /   0   0   5  60
Vidalia         32  62  49  68 /   0   5  10  30




AVIATION...Vaughn is the U.S. government's official web portal to all federal, state and local government web resources and services.