978
FXUS62 KFFC 101144
AFDFFC

Area Forecast Discussion
National Weather Service Peachtree City GA
644 AM EST Fri Jan 10 2025



...New 12Z Aviation Discussion...

.SHORT TERM...
(Today through Saturday)
Issued at 412 AM EST Fri Jan 10 2025

Key Messages:

 - A significant winter storm will impact northern Georgia today,
   leading to hazardous or impossible travel conditions.

 - Ice accumulations of 0.15 to 0.40 inches may lead to power
   outages, especially in northeast Georgia.

 - Snow amounts in the 1 to 2 inch range a possible north of
   Interstate 20, with isolated totals near 3 inches possible on
   the higher mountain peaks.

Winter Weather Threats Through Saturday:

A Winter Storm Warning remains in place for portions of north
Georgia that will experience hazardous or impossible travel
conditions today. Travel is not advised within the warning area, and
should be avoided if possible. If you must travel, ensure that you
have an extra method of staying warm, an extra flashlight, food, and
water in your vehicle in case of an emergency. The latest road
conditions for the state can be obtained by calling 5 1 1. Downed
trees or powerlines may also occur within the warning area,
leading to power outages. Several counties in central Georgia
remain under a Weather Advisory. These counties may experience
hazardous travel due to snow and ice, especially this morning.

As it has been with the prior forecasts, surface temperatures remain
the primary challenge for today. The two main forces affecting the
temperature forecast should be the low surface dewpoints this
morning (evaporative cooling potential) and the potential for low
level WAA this afternoon. Observed surface dewpoints over northern
Georgia were in the teens as of 4 AM. This was on track compared
to the prior forecast. From Macon southwards, dewpoints were in
the mid 20s, and this was a deviation of 6 to 8 degrees (higher)
from the prior forecast. The low surface dewpoints in northern
Georgia should combine with a substantial dry layer (below 700 mb
on the 00Z sounding) in the lower levels of the atmosphere to
produce a significant amount of evaporative cooling this morning.
This should drive temperatures downward, from the current values
in the lower 30s to the upper 20s once precipitation starts. As a
result the initial precipitation type this morning should be snow.
The higher surface dewpoints in central Georgia suggest a lower
evaporative cooling potential and this may limit the potential
time window for a brief burst of snow in this morning. As the day
progress the freezing line should gradually move northwards in
response to low level WAA. The degree to which this will occur
remains in doubt, but the latest CAM runs have been inching it
towards the Atlanta area this afternoon. In northeast Georgia
where colder surface air tends to linger, we may stay at or just
below freezing for the entire event. This suggest the highest
potential for ice accumulations of 0.25 inches or more along a
line from just north of Atlanta to Gainesville to Lake Hartwell.
Snow amounts near an inch could occur in the Atlanta Metro this
morning, but the highest totals 2-3 inches should be limited to
the mountains.

Freezing precipitation will come to and end for most of the
region by 2 AM Saturday. However a few snow flurries could linger
in the mountains of northern Georgia through Saturday morning.
Depending on how substantial ice accumulations are, there could be
a concern for additional power outages on Saturday as northwest
wind gusts creep into the 15 to 25 mph range. Otherwise
temperatures should warm gradually on Saturday, with all but the
higher peaks of the mountains climbing back above freezing. This
should aid in melting, but patches of black ice may reform
Saturday night as temperatures fall back below freezing.

&&

.LONG TERM...
(Saturday night through Thursday)
Issued at 412 AM EST Fri Jan 10 2025

Consistent upper level troughing over the Eastern U.S. will
continue to favor below average temperatures during this period.
No major storm systems appear to be in the pipeline at this time,
though a weak system tracking along the Gulf Coast could bring
some light precipitation to central Georgia on Monday.

&&

.AVIATION...
(12Z TAFS)
Issued at 643 AM EST Fri Jan 10 2025

Conditions are deteriorating rapidly. A TEMPO in place will cover
scattered -SNPL chances before switching over to sleet and a FZRA
mix. VIS could drop below 1SM at times after 15Z as some of the
heavier winter precip starts with CIGS dropping to as lows as OVC005
during the tempo. There remains some uncertainty as to how far south
the freezing precip will reach and there is a chance for ATL to see
some periods of -SHRA before transitioning to a wintery mix for
FZRA. Winds will generally stay on the east side at less than 10
kts.

//ATL Confidence...12Z Update...

Low on weather element.
High on all other elements.

Vaughn

&&

.PRELIMINARY POINT TEMPS/POPS...
Athens          34  29  40  19 / 100 100   0   0
Atlanta         34  30  37  19 / 100  90   0   0
Blairsville     32  26  33  14 / 100  90  10   0
Cartersville    35  29  37  14 / 100  90   0   0
Columbus        40  33  43  22 / 100 100   0   0
Gainesville     33  29  38  18 / 100 100   0   0
Macon           39  32  45  21 /  90 100   0   0
Rome            35  28  37  14 / 100  80  10   0
Peachtree City  36  30  38  17 / 100  90   0   0
Vidalia         46  39  50  26 /  60 100   0   0

&&

.FFC WATCHES/WARNINGS/ADVISORIES...
Winter Storm Warning until 7 AM EST Saturday for GAZ001>009-
011>016-019>025-027-030>039-041>060.

Winter Weather Advisory until 4 PM EST this afternoon for GAZ061-
062-066>076-078-079-081>084-089.

&&

$$

SHORT TERM...Albright
LONG TERM....Albright
AVIATION...Vaughn