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Area forecast discussion 
National Weather Service Tallahassee Florida
936 am EDT Wed Apr 16 2014

Near term [through today]...
after a chilly start across the region this morning with low temps
ranging from the middle 30s to the lower 40s, temps are slowly
climbing through the 40s under mostly sunny skies. High temps are
still expected to remain well below climo this afternoon, with
most locations topping out in the mid to upper 60s despite plenty
of insolation. Therefore, made only a few very minor tweaks to the
current fcst which is well on track.


[through 12z thursday]...
while VFR conditions will hold at the terminals through much of
the period, albeit with some gusty NE winds during the daylight
hours, MVFR level cigs appear to be poised for a return to the taf
sites during the late night and early morning hours.


Prev discussion [325 am edt]...

Short term [tonight through friday]...

The short range period begins with a broad full Continental U.S. Trough
aloft, with surface high pressure wedging down the eastern third
of the country into the southeast. A northern stream +pv anomaly
embedded within the mean trough will drive a strong surface low
into the Great Lakes region on Thursday and subsequently force the
East Coast ridge further east veering low-level flow locally from
the east/southeast. Easterly surface flow will advect a thermal
trough across the Florida Peninsula, into the eastern Gulf creating a
weak east to west temperature gradient as the warmer temperatures
force westward the cooler Gulf moderated temperatures from
tuesday's cold front. This will set up weak isentropic showers
across the northeast Gulf, and areas south of Interstate 10 in
North Florida. Expect shower coverage to remain light and
scattered in nature as upslope vector orientation and magnitude
remain unimpressive.

Thursday night, Gulf cyclogenesis will gradually evolve as a weak
southern stream +pv anomaly merges with the southern extension of
the northern stream anomaly over the northwest Gulf. This entire
system will move eastward through the night, with a surface
trough/low somewhere in the northeast Gulf by morning Friday.
There is a considerable amount of disagreement between pretty much
all of the guidance as to how Friday will pan out. The European model (ecmwf) cuts
off the upper anomaly, separating it from the more progressive
northern stream flow and slowing the entire system. The GFS
however, keeps at least some connection with the northern stream
and thus as a quicker frontal system passage, drying things out by
Friday night. There seems to be more guidance supporting the
slower solution, though the exact position of the surface low
remains unagreed-upon. This will also mean the potential for a
medium duration (24-36 hour) heavy rain event, especially across
The Big Bend and south-central Georgia. Rain may gradually let up
through the day Saturday, but will most likely not come to an end
completely until Sunday morning should the slower solution present
itself. This will only aggravate ongoing river flooding and
could present a risk for more significant flooding. Stay tuned as
we hope for a little better model consensus.

Long term [friday night through wednesday]...

On Monday, zonal flow brings another weak system north of our County Warning Area
but it appears there will only be a slight chance of rain with
this system.


Winds and seas will remain at advisory levels through mid-
afternoon and have thus extended the advisory a few hours in time.
Expect modest easterly winds to at least keep conditions at
cautionary levels through Thursday, before advisory conditions
return ahead of a low pressure system in the Gulf Friday, possibly
lasting through Saturday. Thereafter, winds and seas will
eventually fall to below headline conditions.

Fire weather...

Much drier air has arrived in the area. This combined with a second
day of gusty winds will allow fuels to continue to dry out. However,
the air mass will not be dry enough to be concerned about red flag
criteria, especially considering fuel moisture. Relative humidity will increase
quickly after today with another round of wetting rain expected on


Heavy rains across the Florida Panhandle this morning resulted in sharp
rises on the Chipola River where the Altha gage is cresting about a
foot above moderate flood stage. The river will fall pretty quickly
too and is forecast to drop below flood stage tonight. The St. Marks
river at Newport is now forecast to reach moderate flood stage
tonight and remain there into Saturday evening. Only minor rises
occurred on the Choctawhatchee, Apalachicola and Ochlockonee rivers.
However, it will not be several days before Bruce, Blountstown and
Havana drop below flood stage. Flood waters from the Withlacoochee
and Santa Fe rivers will eventually work through the Suwannee River
which will begin to see stages rise above flood stage early next

The most up-to-date river forecast information can always be found
on our ahps Page (below).



Preliminary point temps/pops...

Tallahassee 70 48 73 60 72 / 0 10 30 50 70
Panama City 68 52 71 60 72 / 0 10 30 50 70
Dothan 66 46 71 56 72 / 0 0 20 40 60
Albany 67 45 71 56 71 / 0 0 20 40 60
Valdosta 68 49 72 60 72 / 0 10 20 40 70
Cross City 72 54 76 62 73 / 0 20 30 50 80
Apalachicola 68 53 71 62 71 / 0 20 30 50 70


Tae watches/warnings/advisories...

GM...Small Craft Advisory until 2 PM EDT this afternoon for Apalachee
Bay-coastal waters from Ochlockonee River to Apalachicola
Florida out to 20 nm-coastal waters from Suwannee River to
Keaton Beach Florida out 20 nm-coastal waters from Apalachicola
to Destin Florida out 20 nm-waters from Suwannee River to
Apalachicola Florida from 20 to 60 nm-waters from Apalachicola
to Destin Florida from 20 to 60 nm.



Near term...Gould
short term...Harrigan
long term...lamers/Walsh
fire weather...wool