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Area forecast discussion 
National Weather Service Peachtree City Georgia
315 PM EDT Friday Aug 22 2014

Short term /tonight through Saturday night/...
the upper ridge continues to be the feature of interest in the short
term...producing hot temperatures and a relative dearth of
convection compared to the last couple of days. Did continue with
slight chance probability of precipitation across the forecast area through sunset to
account for showers and isolated thunderstorms that are popping up
in the heat and resultant instability.

This ridge will continue influencing the region through Saturday
with another day of above normal temperatures and uncomfortable heat
indices. As a result...one more heat advisory has been issued from
noon to 8pm Saturday for some central Georgia counties where heat
indices are forecast to reach or exceed 105 degrees. If possible
limit outdoor activity...drink plenty of water...and check on
elderly neighbors in these areas.

Chance probability of precipitation were included across the northeastern half of the area
as models continue to hint at an upper level disturbance rounding
the periphery of the ridge...which could serve as a focus for
potential development Saturday afternoon. Slight chance probability of precipitation cover
the rest of the area as isolated activity cannot be ruled out with
the heat and instability in place. Some of these storms could become
briefly strong...with a storm or two reaching severe limits not out
of the question.



Rain shower/31



Long term /Sunday through Friday/...
mainly only tweaks to the long term based on the latest guidance.

Bdl

Previous discussion...
upper ridge remains centered west of the County Warning Area at the beginning of
the extended and persists into next week. Backdoor cold front
pushes in for Sunday and thus best chance of probability of precipitation appear to be
during that time period. By Monday...a surface ridge builds across
the northeast...ridging down the Appalachians. Although the wind
will shift to the east with this and clouds will increase...European model (ecmwf)
and GFS are consistent with limiting probability of precipitation Monday night through
Wednesday and are basically showing no precipitation. At this
point...cannot completely follow guidance and with a wedge like
situation and it being summertime have left the mention of a
slight chance of precipitation...at least for the daytime periods. The
other uncertainty with this is the chance of thunder. GFS shows
basically near zero cape...but again with it being
summertime...have left in isolated thunder for the daytime. Will
continue to watch this though over the next few days to see if its
necessary to back off on thunder. Surface ridge across the northeast
shifts eastward and weakens as a cold front approaches for
Thursday. Given this trend...have shown an increase in the chance
of rain/thunder for the end of the extended.

Although temperatures will be slightly cooler on Sunday compared
to Saturday...a few areas across the southern portions of central
Georgia could still creep into the middle 100s for heat index values.
With clouds increasing on Monday...high temperatures should remain in the
80s for much of the County Warning Area.

11

&&

Aviation...
18z update...
expect VFR through the taf period. Should see a few clouds overnight
but no low stratus tomorrow morning. Vcsh suffices for isolated
development through this evening at many locations. Same diurnal scattered cumulus
tomorrow afternoon. Prob30 -tsra included tomorrow afternoon for
convection possible for atl with best chances 18-22z. Winds should
remain northwesterly and relatively light. Portions of eastern Georgia
may see brief north-northeast winds middle-morning Saturday.

//Atl confidence...18z update...
medium confidence for convection impacting katl tomorrow...high
all other elements.

Rain shower/31

&&

Preliminary point temps/pops...
Athens 72 99 73 89 / 5 30 30 60
Atlanta 76 95 76 90 / 5 30 20 60
Blairsville 68 89 68 83 / 10 30 30 60
Cartersville 70 95 72 91 / 5 30 20 60
Columbus 77 99 77 95 / 5 20 20 60
Gainesville 74 93 74 86 / 5 30 30 60
Macon 73 100 74 93 / 5 20 20 60
Rome 70 96 73 92 / 10 20 20 60
Peachtree City 70 96 73 91 / 5 20 20 60
Vidalia 76 100 75 93 / 5 20 20 50

&&

Ffc watches/warnings/advisories...
heat advisory until 8 PM EDT this evening for the following
zones: Baldwin...Bibb...Bleckley...Chattahoochee...Crawford...
crisp...Dodge...Dooly...Emanuel...Glascock...Hancock...Houston...
Jefferson...Johnson...Jones...Laurens...Macon...Marion...
Montgomery...Muscogee...Peach...Pulaski...Schley...Stewart...
Sumter...Taylor...Telfair...Toombs...Treutlen...Twiggs...
Warren...Washington...Webster...Wheeler...Wilcox...Wilkinson.

Heat advisory from noon to 8 PM EDT Saturday for the following
zones: Baldwin...Bibb...Bleckley...Clarke...Crawford...crisp...
Dodge...Dooly...Emanuel...Glascock...Greene...Hancock...
Houston...Jasper...Jefferson...Johnson...Jones...Laurens...
Macon...Monroe...Montgomery...Morgan...Oconee...Oglethorpe...
Peach...Pulaski...Putnam...Schley...Stewart...Sumter...
Taliaferro...Taylor...Telfair...Toombs...Treutlen...Twiggs...
Warren...Washington...Webster...Wheeler...Wilcox...Wilkes...
Wilkinson.

&&

$$

Short term...rw/31
long term....bdl
aviation...rw/31

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