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Area forecast discussion...updated aviation 
National Weather Service Peachtree City Georgia
634 am EST Tuesday Jan 27 2015

Short term /today through Wednesday/...
/issued at 407 am EST Tuesday Jan 27 2015/
temperatures across north Georgia this morning are either freezing or
will be there shortly. Disturbances embedded within the northwest
flow aloft are producing ample low to middle level cloudiness across
north Georgia this morning. Regional radars are suggesting a few patches
of snow flurries may be occasionally occurring across parts of far
north Georgia this morning... and this trend may persist into the early
afternoon for at least northeast Georgia as disturbances continue today.

The main concern this morning continues to be the potential for a
few slick spots on bridges and overpasses across mainly north Georgia
this morning as any lingering moisture freezes. Although nothing
widespread is expect... this potential exist... and therefore will
continue the Winter Weather Advisory as posted through 9 am for this
black ice potential. A few spots in the higher elevations of north
Georgia may not warm above freezing until late morning... so even if the
advisory is allowed to expire at 9 am... it does not mean this
threat has completely ended. All interest in north Georgia should
continue to use caution through the morning hours.

Otherwise... where clouds occur this morning... expect a gradually
clearing this afternoon... except possibly across far northeast Georgia
where clouds may linger... even overnight as disturbances continue
to traverse that area. Ample sunshine is expected for all zones on
Wednesday as a dry northwest flow continues. The cold air advection
pattern will hold temperatures below normal today and tonight...
with all areas seeing lows at or below freezing tonight. A slight
warmup to near normal highs should occur on Wednesday under ample
sunshine and diminishing winds.

39

&&

Long term /Wednesday night through Monday/...
/issued at 407 am EST Tuesday Jan 27 2015/
models continue to become in better phase with the main
influencing features of the long term. These consist of two main
systems...the first of which is a weaker shortwave that is a bit
more moisture starved as well as it is prognosticated to traverse the
upper flow near the Tennessee Valley Thursday afternoon into
overnight. Have kept probability of precipitation down to low end chance mainly across the
north...and still cannot rule out a transition to light snow or
flurries in the higher elevations based on the model thermal
profiles before lingering low level moisture exits.

The second system will likely be of more concern with future
updates as a strong 1030+mb parent surface high looks to set up a
classical cad wedge across the area for Saturday...then while
guidance is in good agreement with ample Gulf moisture
overrunning The Wedge...there are discrepancies on timing of
precipitation onset. The GFS advects moisture faster than the
European model (ecmwf)...bringing in by late Saturday night into Sunday morning
which would make for a more interesting situation. Forecast soundings
and surface wetbulb temperatures by 12z Sunday would support possibility of
wintry mix mainly into parts of the north and east. The forecast
of p-type with this system will greatly depend on the strength of
The Wedge and timing of precipitation onset for the degree of diabatic
enhancement. For now have included chance for snow in parts of the
far north Saturday night into Sunday morning...then again Sunday
night before system exits...though updates may need to shift focus
to northeast Georgia and mixed p-type potential if models show some
run-to-run consistency.

Baker

&&

Fire weather...
/issued at 407 am EST Tuesday Jan 27 2015/
fuels have been too wet recently...therefore even though winds
may reach critical levels today...there does not appear to be fire
danger concern. However if fuels dry enough by Wednesday...then
a high Fire Danger Statement may be issued for much of north and
central Georgia given the forecast afternoon relative humidity values of 20-25
percent. Please stay tuned to future updates with the forecast.

&&

Aviation...
12z update...
MOS guidance and bufr soundings are indicating current middle level
ceilings will scatter around 18-19z today... and remain scattered in
coverage through middle to late afternoon. Then expect mostly clear skies
overnight and on Wednesday. Current west-northwest winds around 7-8kts will veer more
northwest and increase to around 12-14kts with higher gusts to around 22-
25kts by 15-17z today. North-northwest winds around 7-9kts are expected
overnight and on Wednesday. Models are indicating winds may swing over to
NE sometime around 18z Wednesday.

//Atl confidence...12z update...
medium on timing of scattered ceilings. High on all other elements.

39

&&

Preliminary point temps/pops...
Athens 49 27 52 30 / 10 5 0 0
Atlanta 49 30 51 34 / 10 5 0 0
Blairsville 41 24 50 29 / 20 5 0 5
Cartersville 48 27 51 31 / 10 5 0 5
Columbus 54 32 56 34 / 10 0 0 0
Gainesville 46 28 50 33 / 10 5 0 0
Macon 54 29 55 31 / 10 0 0 0
Rome 49 27 51 31 / 10 0 5 10
Peachtree City 51 27 52 31 / 10 0 0 0
Vidalia 54 32 54 32 / 5 5 0 0

&&

Ffc watches/warnings/advisories...
Winter Weather Advisory until 9 am EST this morning for the
following zones: Bartow...Catoosa...Chattooga...Cherokee...
Dade...Dawson...Fannin...Floyd...Gilmer...Gordon...Lumpkin...
Murray...Pickens...Polk...towns...Union...Walker...white...
Whitfield.

&&

$$

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

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