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Area forecast discussion 
National Weather Service Peachtree City Georgia
319 PM EDT Thursday Aug 21 2014

Short term /tonight through Friday night/...
upper ridge has increased across the area with quite a bit of
warming noted in the 12z kffc sounding between 700-850mb. This has
served to suppress convection somewhat. Surface dewpoints are
actually a little lower across eastern zones with SBCAPE values
limited to under 2000 j/kg so even convective cumulus has been slow to
develop...but convection going across portions of north and West
Georgia should continue to drift South. Cape across western zones
exceeding 4000 j/kg with dcape over 1000 j/kg so expect best chance
of isolated severe in those areas.

Ridging will remain in control of the area through the short term so
expect even less coverage of convection tomorrow. So the other big
story is the continued heat. Heat advisory remains in effect for
portions of central Georgia this afternoon and another has been
issued for tomorrow...generally for the same areas. Took a consensus
approach to temperatures and dewpoints since the met continues to be
cooler and more moist vs. The mav warmer and drier. Temperatures
tomorrow are forecast to reach triple digits across portions of
central and eastern Georgia...some of the hottest temperatures seen
in a couple of years.

Tdp

Long term /Saturday through Thursday/...
mainly only tweaks to the long term based on the latest guidance.

Bdl

Previous discussion...
medium range models continue to show little change in the long term
trends across Georgia...at least regarding the persistent upper
ridge expected to dominate for much of the period. Ridge is depicted
at its strongest Friday through Sunday with some weakening by the
first half of next week. Center of the ridge remains west of the
state when the ridge is at its strongest...and I do not believe we
can eliminate probability of precipitation completely...although Friday through Sunday the
chances appear to be slight at best. By Monday through the end of
the period the ridge weakens enough for chance probability of precipitation. Any convection
will show a decidedly diurnal bias. Temperatures will be well above
seasonal normals into the weekend with some moderation by the
beginning of next week as the ridge weakens and the low-level flow
turns easterly.

Big differences in the models with respect to the potential tropical
system in the western Atlantic next week. 00z/06z runs from
yesterday were pushing the system into the Gulf of Mexico but have
deviated significantly with the 12z/18z and now the new 00z runs.
The trend has been progressively more easterly with the medium range
model consensus now keeping the system east of the Atlantic coast.
This is still a long way off and we will likely see quite a bit of
variability in the handling of this potential system over the next
several days.

20

&&

Aviation...
18z update...
VFR through the period except brief MVFR fog possible at mcn
around sunrise Friday morning. Few-scattered cumulus between 4-6kft through
this evening and again Friday afternoon. Winds generally northwest
through the period between 5-10kt afternoons and nearly calm
overnight...though as usual a little higher at atl. Cannot rule
out brief thunderstorms and rain anywhere this afternoon but confidence not high
enough to include more than vcsh in the taf.

//Atl confidence...18z update...
medium on occurrence of convection today...low on impacts to atl.
High on all other elements.

Tdp

&&

Preliminary point temps/pops...
Athens 72 99 74 97 / 20 20 5 30
Atlanta 75 95 75 95 / 20 20 5 20
Blairsville 66 90 66 89 / 20 20 10 30
Cartersville 69 96 71 94 / 20 20 5 20
Columbus 76 99 77 98 / 20 20 5 20
Gainesville 72 95 74 92 / 20 20 5 30
Macon 72 99 73 98 / 20 20 5 20
Rome 70 96 72 95 / 20 20 10 20
Peachtree City 71 96 72 95 / 20 20 5 20
Vidalia 74 101 75 99 / 10 20 5 30

&&

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 Friday 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.

&&

$$

Short term...tdp
long term....bdl
aviation...tdp

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