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000 
FXUS62 KFFC 260548
AFDFFC

Area Forecast Discussion
National Weather Service Peachtree City GA
148 AM EDT Wed Apr 26 2017

.PREV DISCUSSION... /issued 818 PM EDT Tue Apr 25 2017/ 

UPDATE...
Near term forecast doing well. Clouds not expected to increase
ahead of next system until early Wednesday evening. 

SNELSON

PREV DISCUSSION... /Issued 257 PM EDT Tue Apr 25 2017/ 

SHORT TERM /Tonight through Wednesday Night/...
Upper low off the North Carolina coast will continue to pull away 
taking what moisture is left with it. Skies will become clear 
tonight as a weak upper ridge builds over the CWA. The next system 
is already dropping into the southern plains and will start 
spreading low level moisture in the form of clouds into the CWA late 
tonight, mainly over west central Georgia. However dry air aloft 
will remain in place and as soon as mixing occurs Wednesday morning 
the clouds should dissipate. All models agree with a short wave 
being kicked out of the main trough and moving into the Tennessee 
Valley late Wednesday night. This will bring increasing pops to 
northwest GA late Wednesday night. MOS guidance temps look 
reasonable although have made minor adjustments based on local bias 
tables.

17

LONG TERM /Thursday through Tuesday/...
Only tweaks to the long term based on the latest guidance.
Still decent chances for showers and storms on Thursday.
The risk for severe storms still looks to be marginal.

BDL

PREVIOUS GUIDANCE...
Dry conditions from the short term period will carry over into the 
long term for a brief period of time. On Wednesday night...a weak 
mid level shortwave ridge will be pushing east of the local 
area...with associated weak area of sfc high pressure also moving 
east with it into the Atlantic. Although conditions will remain dry 
into the very early morning hours Thursday...a cold front will be 
approaching from the west. Plenty of instability along and in the 
near vicinity of the frontal boundary will help sustain 
thunderstorm activity. As of right now...widespread severe weather
does not seem likely...however enough shear in the vicinity of a 
LLJ across northwest and portions of north central Georgia may be 
enough for isolated severe weather in the morning hours. This 
isolated threat may shift to central Georgia Thursday afternoon as
better shear moves into this area ahead of the frontal boundary 
and may be able to work in tandem with diurnal heating. Main 
threats Thursday look to be gusty winds and hail /as mid level 
lapse rates expected to remain over 6C/km/...though a brief...very
isolated tornado isn't out of the question across northwest 
Georgia Thursday morning /0-1km shear >30kts with dewpoints rising
to near 60/.

At least a portion of this frontal boundary will stall across 
Georgia Thursday night into Friday as the parent system moves well 
north. As this occurs...a closed mid level low will begin developing 
across the Southern Rockies within a broad cyclonic flow regime. The 
digging nature of this feature will help build a midlevel 
subtropical ridge into the Southeast /with Bermuda sfc high also 
building into the region/. This will lift the stalled frontal 
boundary north as a warm front and push a rather moist and unstable 
/dewpoints perhaps mid-upper 60s/ airmass into the Southern US. This 
unstable airmass will promote the development of diurnally driven
thunderstorm activity Friday through Sunday...where warm frontal 
forcing/orographic forcing will likely also enhance lift for 
thunderstorms on Friday across far north Georgia. Anything severe 
Fri-Sun would be of the pulse variety at this point. As the closed
low induces sfc cyclogenesis over the Southern Plains this 
weekend...it will pivot northeast into the Great Lakes by early 
next week. This will push another cold front towards the area 
Monday. Too early to determine severe potential...though shear 
improves with better upper level jet support. A return to stable 
and cooler conditions will follow this fropa just outside of the 
extended.

Kovacik

&&

.AVIATION...
06Z UPDATE...

After a long period of low clouds and periods of SHRA and
TSRA...we finally have some VFR conditions areawide. These VFR 
conditions will persist through today with only a wind shift to
worry about at ATL. Winds could actually fluctuate between SSW and
SSE throughout the day but for now will just show one shift at
21Z. Increasing low clouds and threat from TSRA aft 09Z Thu. Have
included Prob30 for now which will eventually need to be converted
to a TEMPO or Prob30.

//ATL CONFIDENCE...06Z UPDATE...
Medium on wind shift.
High on remaining elements.

Deese

&&

.PRELIMINARY POINT TEMPS/POPS...
Athens          85  61  80  65 /   0  20  60  40 
Atlanta         83  63  78  66 /   0  30  60  30 
Blairsville     82  56  75  54 /   0  30  60  30 
Cartersville    86  62  78  63 /   0  30  60  20 
Columbus        85  63  82  68 /   0  30  60  20 
Gainesville     83  62  77  63 /   0  30  60  40 
Macon           86  60  83  66 /   0  20  50  40 
Rome            86  61  78  61 /   0  40  60  20 
Peachtree City  83  61  79  64 /   0  30  60  30 
Vidalia         86  63  87  68 /   0  10  30  20 

&&

.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

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