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Area forecast discussion...updated aviation 
National Weather Service Peachtree City Georgia
640 am EST Monday Jan 26 2015

Short term /today through Tuesday/...
/issued at 342 am EST Monday Jan 26 2015/
main concern continues to be the slight potential for some light
snow accumulations in the higher elevations of mainly northeast Georgia
this morning. Latest satellite water vapor imagery shows an upper cold
core low spinning over eastern Kentucky/Tennessee and drifting eastward. The
associated surface low is only slightly east of the upper lows
position. The wrap around moisture on the backside of this system is
very limited... and only able to produce the occasional small band
of light rain back across parts of Tennessee and pushing into parts of
north Georgia this morning. So far this has been extremely patchy and
light in nature due to the lack of available moisture. Area
observations show above freezing temperatures all the way back into Kentucky...
so not expecting freezing temperatures to be able to advect into north Georgia
until maybe around sunrise... and this would be mainly in the higher
elevations if occur at all. However... do expect middle 30s to spread
into north Georgia... and these temperatures would support light snow reaching
the ground if impulses on the backside of the upper low can squeeze
out enough moisture to produce a few bands of precipitation through mainly
this morning. Due to lack of moisture and overall dry trends... not
expecting any snow accumulations across north Georgia except maybe in the
higher elevations of northeast Georgia this morning where forcing...
moisture and temperatures might be more favorable this morning. If this
does occur... it would be light... maybe somewhere from a light
dusting to a half inch for elevations generally above 1500-2000 feet
and possibly near an inch in the highest peaks. For this reason...
plan to cancel the Winter Weather Advisory for northwest Georgia... but
will hold onto the advisory for parts of northeast Georgia through 7 PM
this evening... just to play it safe.

Temperatures in the north Georgia mountains are expected to dip below
freezing by early to middle this evening... and any lingering moisture
on roadways could freeze and result in a few patches of black ice.
However... increasing northwest winds today and lack of precipitation should
allow for plenty of drying to occur this afternoon... and therefore
suspect the black ice threat will be minimal... but will monitor
this potential closely through the day... and Post a statement or
advisory for this threat if conditions warrant later today.

Otherwise expect northwest winds to increase into the 15 to 25 miles per hour
range today with higher gusts. This will warrant the issuance of a
Wind Advisory for all areas from 9 am through 8 PM today.

A series of disturbances may keep much of north Georgia cloudy and
produce a few snow flurries in the far northeast Georgia mountains
tonight and Tuesday... but no additional accumulations are expected.
Elsewhere... expect clearing conditions and a dry northwest flow to
prevail through Tuesday. A cold air advection pattern will hold
temperatures at or below normal through the period.

39

&&

Long term /Tuesday night through Sunday/...
/issued at 342 am EST Monday Jan 26 2015/
models getting into better agreement with at least the next
shortwave prognosticated to swing southeast near the area for
Thursday/Thursday night. European model (ecmwf) has backed off some in
amplitude...trending closer to the more consistent GFS...though
still maintains a less progressive timing. Thermal profiles looking
less likely for wintry precipitation in the far north...but enough to hint
at least a slight chance for light snow in the northeast mountains
Thursday night.

Mostly zonal flow aloft returns for end of the week into the
weekend...then more uncertainty exists with the second potential
system. Looking like next best chance for precipitation would be Saturday
night into Sunday...mainly rain though again cannot shake at least
slight chance for snow again in the far northeast.

Baker

&&

Aviation...
12z update...
expect MVFR ceilings to prevail through the morning...with occasional patches of
-ra through around 15z expect improvement to VFR middle level ceilings by
18z... then scattering by 23z. An upper disturbance may spread some
middle level ceilings back into the Atlanta taf sites tonight around 09z.
These ceilings should scatter by 12-14z Tuesday. Current west winds around 7-
9kts will veer northwest by 14-15z and increase to around 12-15kts with
gusts to 20-25kt. The gusty northwest winds persist through around 23z this
evening. Expect west-northwest winds around 7-10kts tonight... and on Tuesday.

//Atl confidence...12z update...
medium to high on all elements.

39

&&

Preliminary point temps/pops...
Athens 50 29 51 29 / 20 5 0 0
Atlanta 46 34 49 31 / 20 5 0 0
Blairsville 41 26 42 24 / 40 20 20 5
Cartersville 44 30 48 28 / 20 5 0 0
Columbus 52 34 54 33 / 10 0 0 0
Gainesville 45 30 47 29 / 40 10 0 0
Macon 54 31 55 31 / 10 0 0 0
Rome 44 30 50 28 / 20 5 0 0
Peachtree City 47 30 51 29 / 10 0 0 0
Vidalia 56 34 56 34 / 10 0 0 0

&&

Ffc watches/warnings/advisories...
Wind Advisory from 9 am this morning to 8 PM EST this evening
for the following zones: Baldwin...banks...Barrow...Bartow...
Bibb...Bleckley...Butts...Carroll...Catoosa...Chattahoochee...
Chattooga...Cherokee...Clarke...Clayton...Cobb...Coweta...
Crawford...crisp...Dade...Dawson...DeKalb...Dodge...Dooly...
Douglas...Emanuel...Fannin...Fayette...Floyd...Forsyth...
Gilmer...Glascock...Gordon...Greene...Gwinnett...Hall...
Hancock...Haralson...Harris...heard...Henry...Houston...
Jackson...Jasper...Jefferson...Johnson...Jones...Lamar...
Laurens...Lumpkin...Macon...Madison...Marion...Meriwether...
Monroe...Montgomery...Morgan...Murray...Muscogee...Newton...
north Fulton...Oconee...Oglethorpe...Paulding...Peach...
Pickens...Pike...Polk...Pulaski...Putnam...Rockdale...Schley...
South Fulton...Spalding...Stewart...Sumter...Talbot...
Taliaferro...Taylor...Telfair...Toombs...towns...Treutlen...
Troup...Twiggs...Union...Upson...Walker...Walton...Warren...
Washington...Webster...Wheeler...white...Whitfield...Wilcox...
Wilkes...Wilkinson.

Winter Weather Advisory until 7 PM EST this evening for the
following zones: Dawson...Fannin...Gilmer...Lumpkin...Pickens...
towns...Union...white.

&&

$$

Short term...39
long term....Baker
aviation...39

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