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Area forecast discussion 
National Weather Service Tallahassee Florida
343 am EST Fri Jan 30 2015

Near term [through today]...
a weak cold front will move through the area early this morning,
ushering in slightly cooler temperatures with afternoon highs
ranging mainly from the upper 50s to lower 60s. Clouds will decrease
rapidly during the morning hours with mostly sunny conditions
expected by afternoon.

Short term [tonight through sunday]...
high pressure will build across the southern Appalachians this
evening and remain north of the region before sunrise on Saturday.
Enough wind will probably keep freezing temperatures confined to
the northern zones, closer to the center of the high pressure
area.

High pressure moves quickly east of the region on Saturday with
southerly flow starting the moistening trend late in the
afternoon. Temperatures will rebound slightly, generally in the
lower 60s across the region, except mid 60s in the Florida Big
Bend.

Saturday night through Sunday, a large storm system will be moving
eastward across the plains, resulting in increasing cloudiness and
eventually rain chances Sunday afternoon. The models tend to be a
little slow developing areas of rain in isentropic events, and
thus have increased pops a little above guidance on Sunday
afternoon into the 40 to 50 percent range in our western areas.

Long term [sunday night through friday]...
the storm system at the tail end of the short term period will
begin to move through the region on Sunday night. With the surface
low well to the north, enough instability will likely be present
within the warm sector to support isolated thunderstorms. After
the isentropic ascent ends on Sunday evening, overall lift looks
minimal until the cold front gets closer to the region after
midnight. Rain chances have been increased into the likely
category for the frontal passage overnight.

Drier and cooler air will move in behind the storm system Monday
afternoon with high pressure settling over the area briefly on
Tuesday.

Up until the 30/00z guidance came in, it appeared that the models
were converging on a similar solution. However, while the overall
pattern remains similar between the GFS and Euro, the 30/00z Euro
slowed down quite a bit and is now 18-24 hours slower with the
progression of the next system. As a result, the forecast for
Wednesday through Friday remains more uncertain than normal.

The pattern suggests that the large upper low over Baja California
will eject eastward across northern Mexico and lead to development
of a surface low pressure area along a stalled frontal zone in the
Gulf of Mexico. The 30/00z GFS stays fairly progressive, even
pulling the upper low well to the north ahead of a deepening
northern stream shortwave. So the heaviest period of rain is
focused on Wednesday afternoon/evening. The 30/00z Euro is much
slower with the evolution of the system, owing to less
amplification of the northern stream by mid week. Thus, while rain
chances increase in the Euro solution Wednesday night, the period
of heaviest rainfall wouldn't occur until Thursday and then linger
into Friday.

There's enough overlap in the solutions to increase pops on
Wednesday but the differences also suggest that rain chances need
to be maintained in the forecast through at least Thursday
afternoon until the timing differences between the models can be
resolved.

&&

Aviation...
[through 12z saturday] a few areas of MVFR ceilings are possible
early this morning as a weak cold front moves through the area,
but otherwise VFR conditions will prevail with gusty northwest winds from
mid-morning until around sunset.

&&

Marine...
winds will increase to advisory level over the western marine area
immediately behind the cold front and then decrease to cautionary
levels through Saturday morning when high pressure will build near
the waters. Onshore flow will increase on Sunday ahead of the next
storm system with possible advisory level conditions Sunday
afternoon. A cold front will move through the marine area on
Monday, shifting winds to offshore.

&&

Fire weather...
red flag conditions are not likely over the next several days.

&&

Hydrology...
river flooding from last week's heavy rainfall is ending this
morning with all of the river points below flood stage.

The next storm system arriving Sunday into Monday looks to bring
widespread rainfall totals of 0.75 to 1.5 inches of rain. These
amounts will likely provide for a small rise in river levels
but is unlikely to result in a return to flood stages at any of
the forecast points.

With streamflows projected to be above to well above normal early
next week, the scenario is set well for river flooding with the
stronger storm system due to approach the area on Wednesday. While
timing differences make overall rainfall amounts uncertain, the
general pattern suggests a widespread moderate rainfall event that
will likely result in at least minor river flooding late next week
or weekend.

&&

Preliminary point temps/pops...

Tallahassee 62 35 64 44 67 / 0 0 0 0 30
Panama City 59 39 60 49 66 / 0 0 0 10 40
Dothan 57 34 59 44 63 / 0 0 0 10 60
Albany 58 32 60 42 64 / 0 0 0 0 30
Valdosta 60 34 64 44 68 / 0 0 0 0 20
Cross City 66 35 67 44 70 / 10 0 0 0 20
Apalachicola 63 40 60 49 66 / 10 0 0 0 30

&&

Tae watches/warnings/advisories...

Florida...none.
Georgia...none.
Alabama...none.
GM...Small Craft Advisory until 4 PM EST this afternoon for coastal
waters from Apalachicola to Destin Florida out 20 nm-waters from
Apalachicola to Destin Florida from 20 to 60 nm.



&&

$$

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

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