Area Forecast Discussion
Issued by NWS Atlanta, GA
FXUS62 KFFC 272335
Area Forecast Discussion
National Weather Service Peachtree City GA
735 PM EDT TUE SEP 27 2016
For Aviation/00z TAFs.
Showers and thunderstorms continue to move south of the metro as
the associated surface front tracks through central GA. Some
activity may continue to instigate along this weak trough with
sufficient convergence, as seen along I-20/east Taliaferro. Feel
precip activity should diminish in the next couple of hours with
loss of heating/instability. Should be fairly quiet overnight with
winds decoupling and any convective debris shearing out. Lows
expected to be in the mid 50 across the northern tier to the
mid/upper 60s across central/southern GA.
.PREV DISCUSSION... /Issued 323 PM EDT TUE SEP 27 2016/
SHORT TERM /Tonight through Wednesday Night/...
Surface front is making its way across north and central Georgia
this afternoon but the cooler/drier air is still a day away. A few
showers and storms are popping up over the higher elevations of
northeast GA where better low lvl forcing exists. Additional showers
are developing in the "warm sector" south of a Columbus to Macon
line. No major impacts expected at this time, but a few stronger
storms could generate brief gusty winds and locally heavy rain.
Through this evening, models are trying to focus convection along
and between the I-85 and I-20 corridors which is where a SW-NE
instability axis exists at this time. Loss of heating after sunset
will quickly diminish much of the convection as cooler/drier air
begins to filter across our northwest GA counties overnight.
Wednesday...the front, still lingering across east-central to
southwest GA, should generate additional shower/thunderstorm
activity by early afternoon. The drier air will definitely be felt
from ATL metro and points north/west with good mixing -- dewpts
possibly falling into the 40s/lwr 50s by late in the day.
Temperatures will finally respond overnight (Wednesday) cooling down
to the 50s across much of the area (except extreme south/east).
LONG TERM /Thursday through Tuesday/...
A strong short wave will rotate around the upper low Thursday.
Lapse rates increase and there will be moisture available. Will
therefore add slight chance pops to the mountains Thursday.
Otherwise made just minor changes to temps based on new guidance.
Dry air will be spreading into the CWA through Thursday. This will
allow humidities to drop to near 25 percent for an hour or two
Wednesday afternoon across northwest Georgia. Fuels at this time
are running around 10 percent. However time requirements will not
be met for a Fire Danger Statement. This will continue to be
VFR conditions should prevail through much of the TAF period as a
front will continue to move south overnight ushering in drier
conditions. However, have noticed some activity initiating northwest
of the metro TAF sites, likely due to upper level support. So have
placed a TEMPO between 00Z-03Z to account for any lingering
TSRA/gusts. Otherwise, expect precip to diminish through the
evening hours with calm and clear conditions through the rest of
the overnight period. Based on cond pres def, feel AVN may have
the best chance for early morning fog. The front should be across
the southern tier with light west winds. Have VCSH across MCN
tomorrow afternoon to account for any showers along the front.
//ATL Confidence...00Z Update...
Medium to High on Convection during through 03Z time period. High
on all other elements.
.PRELIMINARY POINT TEMPS/POPS...
Athens 66 85 58 80 / 30 20 5 5
Atlanta 66 84 60 75 / 20 5 5 5
Blairsville 56 78 51 69 / 20 5 10 20
Cartersville 59 83 55 74 / 20 5 5 5
Columbus 69 89 62 83 / 20 10 5 5
Gainesville 65 82 58 75 / 20 10 5 10
Macon 68 89 60 85 / 30 20 5 5
Rome 57 83 54 74 / 10 0 10 10
Peachtree City 64 85 56 77 / 20 10 5 5
Vidalia 70 89 67 87 / 20 40 20 10