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Area forecast discussion 
National Weather Service Tallahassee Florida
357 am EDT Thu Sep 18 2014

Near term [through today]...

With the sfc cold front expected to be pushed further to our south
today, much drier air will advect in from the northwest. This will
allow dewpoints to mix out into the lower to middle 60s away from
the coast this afternoon. Although dry, it will still be quite warm
across the region today, with high temps climbing into the upper 80s
to lower 90s under partly cloudy skies. Rain chances should also be
limited to the coastal waters, with pops no higher than 20-30%.



Short term [tonight through saturday]...

Two distinct features will play an important role in the evolution
of the synoptic pattern and subsequently convective coverage
through Saturday. The first is an upper level +pv anomaly, or
shortwave, currently centered over eastern South Dakota. The
second is a ribbon of mid-level +pv created by convection along
a stationary boundary draped northwest to southeast through the
Central Plains. These two features will "merge" as they enter the
southeast, with the mid-level anomaly forcing the upper shortwave
to cutoff from the more progressive northern stream flow.

On Friday, expect the best deep layer synoptic ascent associated
with the shortwave to be just south and east of our southeast Big
Bend counties. This will place the main +pv anomaly directly over
the tri-state region by the afternoon. The result of this will be
a strengthening surface ridge and associated wedge of cooler air
pressing southwest into our region. This relatively weak boundary
should be strong enough to initiate some convection along its
leading edge. Though, the vertical extent of these storms should
be limited with plenty of dry air slipping in aloft.

On Saturday, the mid-level anomaly will have amplified the upper-
level cutoff low over southeast Georgia. Both of the
aforementioned features will have induced low-level cyclogenesis
over the western Atlantic, placing the the region under a fairly
strong low-level northeasterly flow regime. The northeasterly flow
will lift from the warm western Atlantic, over the "cool" wedge
that established itself over the southeast. This will likely
spread an area of showers inland, moving from northeast to
southwest through the day. It is unlikely that these showers will
make it too far west of a line from Tallahassee to Albany.

Expect afternoon highs on Friday to range from around 90 degrees
along the Florida Panhandle and across southeast Alabama, to the
middle 80s across much of Georgia. On Saturday, the middle 80s
will be more common area-wide.



Long term [saturday night through thursday]...

The long term period begins with the upper low off the Florida
East Coast being pulled northward ahead of a deepening eastern
Continental U.S. Trough. Drier conditions will return by Sunday afternoon
ahead of an approaching frontal boundary. With the main upper
level forcing transitioning from the Ohio Valley to New England
Mon-Tue, it continues to appear that the next cold front will
stall near or just north of the forecast area on Tuesday.
Thereafter, with the boundary in place and low level flow shifting
to easterly, a period of moist and unsettled conditions will
likely return.

&&

Aviation...
[through 12z friday]

VFR conditions should prevail at the terminals through much of
the upcoming time frame, with the exceptions of brief periods of
MVFR vis at dhn, aby, and vld overnight and early this morning.
Otherwise, light winds and just sct cumulus and cirrus from time to time
will dominate the skies.

&&

Marine...

Relatively light winds today will shift northeast and increase to
near cautionary levels Friday night into Saturday. Thereafter,
the pressure pattern will weaken again, lowering winds well below
headline levels.

&&

Fire weather...

The influx of drier air into the region will peak this afternoon,
but relative humidities and other critical fire weather parameters
will not approach red flag levels during the next several days.

&&

Hydrology...

With generally light rainfall amounts expected through the
weekend, streamflows will be in recession for the next few days.

&&

Preliminary point temps/pops...

Tallahassee 92 68 89 68 84 / 10 10 40 30 40
Panama City 89 71 88 71 86 / 10 10 30 40 30
Dothan 90 66 88 67 85 / 10 0 40 30 10
Albany 89 67 86 67 84 / 10 10 40 20 40
Valdosta 92 68 86 66 83 / 10 10 40 20 50
Cross City 91 70 86 65 84 / 10 30 50 40 60
Apalachicola 89 71 87 71 83 / 10 10 30 50 40

&&

Tae watches/warnings/advisories...

Florida...none.
Georgia...none.
Alabama...none.
GM...none.

&&

$$

Near term...Gould
short term...Harrigan
long term...Godsey
aviation...Gould
marine...Harrigan
fire weather...Gould
hydrology...Harrigan/Godsey

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