Area Forecast Discussion
Issued by NWS Atlanta, GA

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FXUS62 KFFC 041920

Area Forecast Discussion
National Weather Service Peachtree City GA
220 PM EST Sun Dec 4 2016

.SHORT TERM /Tonight through Monday Night/...
Short range models continue to show a wet pattern as a series of
disturbances embedded within the southwest flow aloft continue to
overrun a cool easterly flow near the surface to produce periods of
light to moderate rain. May see a short break in the rainfall early
on Monday as an upper low deepens over SW TX which results in slight
ridging aloft here... but areas of rain should spread back into the
area by Monday afternoon/evening as the upper low begins to kick
eastward. Still thinking the wedge of cool/stable air will greatly
hinder any thunderstorm threat through this short term... but will
have to monitor the far southern reaches Monday night for this
potential as the wedge front begins to retreat northward and a
warm/moist unstable airmass begins to creep into areas generally
along and south of a Columbus to Vidalia line by early Tuesday
morning. Otherwise... will continue to word for just rain/rain
showers for now... along with some patchy fog and drizzle tonight as
clouds lower to near the surface.

Latest WPC and model guidances are suggesting the heaviest rainfall
axis will set up south of the I-85 Corridor where rainfall amounts
of 1 to 3 inches are possible over the next 36 to 48 hours. These
amounts over this area should not be enough to cause any significant
flood concerns at this time... but if the heaviest rainfall axis
shifts northward... cannot rule out some brief minor flooding along
any of the typical flood prone creeks in the Atlanta area. Will have
to monitor this potential closely over the next couple of days.

The clouds and cool rain will continue to hold area temps in the 40s
overnight... but the break in the rain on Monday may be sufficient
to allow area temps to creep into the 50s Monday afternoon. If this
happens... clouds will likely hold area temps in the upper 40s to
lower 50s for lows Monday night. Mos pop and temp guidances were
close and looked reasonable... so did not stray far.


.LONG TERM /Tuesday through Sunday/...
Mainly only tweaks to the long term based on the latest guidance.
Most precip chances will be ending late Tuesday into the evening.

Once again, no significant changes to the general Long-Term Forecast
trends. Medium-range models continue to show consistency with
previous trends and fairly good agreement amongst each other, at
least through mid-week. Although we are still seeing the models
generate some instability late Monday night and Tuesday, mainly
across the south still, the numbers are not impressive and low-
level shear is near negligible. I have kept the slight chance for
thunder in across western and southern areas Monday night and
across the south Tuesday, but prospects for any severe weather
remain low.

Models diverge a bit concerning the evolution of the the remainder of
the extended forecast period. Both bring in the coldest air of the
season so far behind the system later in the workweek, but there are
noticeable differences in timing of the cold air as well as the
precipitation chances ahead of the cold surge. My late week grids are
basically a compromise between the two for now.



18Z Update...
IFR CIGS should prevail until late this afternoon or early
evening when CIGS lower to LIFR as -radz persist overnight. Once
LIFR CIGS settle in... they should remain there through late Mon
morning. Expect some CIG improvement to at least IFR levels Mon
afternoon as a break in the rain is expected. Rains spread back in
by late Mon afternoon... and this may lower CIGS back down to LIFR
by Mon evening. Winds will remain easterly 10-12kts with a few
gusts this afternoon... then winds back more NE tonight and
diminish to around 6-8kts. East winds return on Mon with speeds
around 6-8kts.

//ATL Confidence...18Z Update...
Medium on timing of LIFR cigs this evening.
High on remaining elements.



Athens          43  55  49  60 /  90  70 100 100
Atlanta         45  56  52  63 /  80  90 100  90
Blairsville     41  57  46  55 /  80  80 100  90
Cartersville    45  55  51  62 /  80  90 100  90
Columbus        51  60  58  70 /  80 100 100  70
Gainesville     42  55  48  58 /  90  80 100  90
Macon           49  60  56  73 /  80  90 100 100
Rome            44  55  51  62 /  70  90 100  70
Peachtree City  45  57  52  66 /  90  90 100  90
Vidalia         57  64  61  76 /  70  80 100  90




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