Area Forecast Discussion
Issued by NWS Atlanta, GA
FXUS62 KFFC 220750
Area Forecast Discussion
National Weather Service Peachtree City GA
350 AM EDT Wed Mar 22 2017
.SHORT TERM /Today through Thursday/...
Early morning patchy fog/reduced vsbys expected for parts of north
GA (mainly along and north of north Atlanta metro to Athens line)
due to residual moisture from yesterday evening MCS. The backdoor
front impinging from the north and resultant drier dewpt gradient
should help from keeping any fog development from becoming more
widespread or thicker coverage but will monitor near term trends.
Aforementioned front has a fairly narrow band of enhanced low level
moisture to accompany it as it advects southward today. Have
therefore included slight pops for any isolated showers mainly in
portions of central GA by this afternoon and kept trends close to
short term hi-res consensus. Driving parent sfc high slides east of
Cleveland by late this afternoon/evening which begins the eastern
component of the low level fetch for the area as inverted ridging of
a rather short-lived classical CAD sets up along the slopes of the
eastern Appalachians. Guidance has less moisture overrunning than
before and a rather rapid shift of the sfc high southeastward by
early Thursday so trended temps a bit higher than before and kept a
dry fcst. See fire weather section below for details on resultant RH
.LONG TERM /Thursday Night through Tuesday/...
Surface high pressure anchored across the mid-Atlantic will remain in
control through Saturday. This high eventually shifting out to
sea with ridging aloft being undercut by an approaching trough
Saturday morning. Expect increasing clouds Saturday
afternoon/evening as the next storm system approaches. In the mid-
levels, a closed low dropping out of the Rockies will pivot
toward the Ohio River Valley through the weekend. A cold front
associated with this system will continue to track east across the
central CONUS, becoming washed out before reaching Georgia. In
addition, the dynamics associated with this system will lift north
as it approaches Saturday night into Sunday. Anticipate showers
will move into northwestern Georgia Saturday afternoon/evening.
With very little surface convergence and much of the energy within
the mid-levels waning, do not have the highest confidence that
this system will hold together, especially into Sunday. Therefore,
current thinking is highest pops across the far northern tier of
Georgia with the rest of the area experiencing scattered showers.
Also, given weak instability and shear, kept schc thunderstorm in
Saturday evening through Sunday. The system will lift to the north
with the front never making it into Georgia. The next impulse
(albeit weaker) will be taking a similar track approaching
Tuesday. This will bring a chance of showers and thunderstorms for
the first half of the work-week.
Apart from normal temperatures expected Friday, we are forecasting
above normal temperatures through the rest of the long term as
southerly flow remains locked in across the region.
A ridge of high pressure will build into the area behind a frontal
passage today and allow for dry conditions today into Thursday.
While resultant RH values should stay outside critical levels this
afternoon, eastern portions of the area could reach near 25 percent
for several hours Thursday afternoon. This combined with previous
dry fuels for some areas could warrant a high fire danger statement
Thursday. North to NW winds today should shift east this afternoon
into Thursday, though magnitudes will be below critical levels.
Initial VFR conditions becoming MVFR cigs across the northern
sites for much of the morning behind the evening storm complex.
Could be lower with some reduced VSBYs at times with lingering low
level moisture but will monitor trends if any updates warrant.
Otherwise expect BKN/SCT coverage in 4-5 kft range with some
midday/afternoon enhancement from a weak boundary pushing
southward. NW winds to start things off switching NE after about
21-00z for KATL. Magnitudes should be 8-12 kts overall. Late
period transition to easterly 8-10 kts.
//ATL Confidence...06Z Update...
Low on early morning cigs/vsbys.
High on all else.
.PRELIMINARY POINT TEMPS/POPS...
Athens 70 42 58 44 / 10 5 10 5
Atlanta 70 46 61 48 / 20 5 10 5
Blairsville 64 37 56 41 / 10 5 10 5
Cartersville 67 44 61 47 / 20 5 10 5
Columbus 76 52 66 52 / 20 10 10 5
Gainesville 69 42 58 45 / 10 5 10 5
Macon 76 49 65 46 / 20 10 10 5
Rome 66 43 63 48 / 20 5 10 5
Peachtree City 71 46 61 46 / 20 5 10 5
Vidalia 76 50 65 48 / 10 10 10 5