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Area forecast discussion 
National Weather Service Tallahassee Florida
1217 PM EDT Thu Jul 24 2014

Near term [through today]...
analysis shows an upper level trough extending from the Great Lakes
to northern Alabama this morning. This will likely help with
afternoon/evening convection. With southerly flow dominant, there
is ample moisture and instability with afternoon heating. Thus
there is a higher chance for showers and thunderstorms today
compared to the past few days. Convection currently over the
Panhandle region will likely spread throughout most of the County Warning Area
into the afternoon hours. Max temps may be slightly hampered in
areas with more rain and cloud cover particularly the Panhandle
region. Although highs will still be in the low 90s inland.

Long term [saturday night through thursday]...
while initially, a typical summertime pattern will be in place
across the southern United States at the start of the period, expect
the pattern to rapidly amplify by Monday as a large trough digs
southward out of Canada. Some of the guidance suggests this trough
will be strong enough to help push a cold front into and possibly
past the forecast area on Tuesday delivering another brief but
noticeable cool and dry period to the region through Wednesday. The
upper pattern thereafter looks to stagnate with strong ridging
building over The Rockies and across the western North Atlantic
keeping the deep trough in place from the Ohio Valley to the
northeastern Gulf. This will yield slightly cooler and less humid
conditions by the end of the period with only modest rain chances.

&&

Prev discussion [632 am edt]...

Short term [tonight through saturday]...

The GFS and European model (ecmwf) are in good agreement in maintaining the base of
a weak 500 mb trough over Georgia through Saturday, while a surface cold
front stalls well to our north. The mean 1000-700 mb wind across
our regions will be out of the southwest, which is often
associated with above-climatology pops for portions of our
forecast area (especially in fl). Curiously, there is considerable
difference in the forecast pop among the GFS, NAM, & European model (ecmwf) MOS
each day, but it's not that obvious (looking at the synoptic
scale) why this is. We averaged the various pops together, as well
as our local sea breeze climatology, and our pop forecast changes
very little between Friday and Saturday. Scattered evening
thunderstorms (mainly in Georgia and al) will dissipate before midnight
tonight, but isolated showers/storms will begin to develop near the Florida
coast by dawn on Friday. Pops both Friday and Saturday are around
40%, which is near climatology. Highs will be in the mid 90s and
lows in the 70s.

The prospects for organized severe thunderstorms continues to be
low due primarily to weak winds aloft. However, the GFS, ECMWF,
and NAM all forecast some drying and steepening of the mid
tropospheric lapse rates Saturday afternoon. SBCAPE values will
likely exceed 2500 j/kg on Saturday, and Delta Theta-E values are
forecast to reach or exceed 30 k. Together, these factors suggest
a greater potential for strong/severe wet microbursts, albeit
disorganized and "pulsey" in nature, and we will continue to
monitor this threat.



Aviation...
[through 12z friday] VFR conditions are expected to prevail for
most of the day with winds from the southwest around 8-10 kts in
the afternoon. The typical summertime scattered diurnal convection
will develop during the late morning and afternoon hours with thunderstorms in the vicinity
shown at the terminals. The earliest start is expected at ecp with
later start times farther to the north and east.



Marine...

An east-west oriented surface ridge will remain across South Florida
and the southeast Gulf of Mexico through this weekend. Winds will
generally be from the southwest around 10 kt, except for an
increase to 10 to 15 knots near the coast during the late afternoon
and evening hours from strong daytime heating. Significant wave
heights will be mainly 2 ft or less.



Fire weather...

Red flag conditions are not expected over the next several days,
although dispersion values will be high this afternoon across a
large portion of the area away from the immediate coast.



Hydrology...

Any heavy rain that occurs is likely to be too localized to
significantly impact local rivers. The probability of flash
flooding is very low.

&&

Preliminary point temps/pops...

Tallahassee 91 73 93 73 94 / 50 10 40 20 40
Panama City 87 77 89 77 89 / 50 10 40 20 40
Dothan 91 73 92 74 94 / 50 30 40 20 40
Albany 93 73 93 74 94 / 40 40 30 20 30
Valdosta 96 72 96 71 96 / 40 20 40 20 40
Cross City 92 74 91 71 92 / 30 30 40 20 40
Apalachicola 89 77 89 77 89 / 40 10 40 20 40

&&

Tae watches/warnings/advisories...

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

&&

$$

Near term...McDermott
short term...Fournier
long term...Godsey
aviation...dvd
marine...Fournier
fire weather...dvd
hydrology...Fournier

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