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Area forecast discussion 
National Weather Service Tallahassee Florida
328 PM EST Sat Dec 27 2014

Near term [through tonight]...

Weak surface high pressure will continue to push eastward off of the
mid-Atlantic coast today as a deepening upper level trough swings
across the southwestern Continental U.S.. the surface cold front in Texas has
made some eastward progress today, with showers and thunderstorms
out ahead of it. Coverage will remain highest to our west, but southeast Alabama
and the Florida Panhandle have 30-40% chance of seeing light rain at some
through tonight. Highs will be in the upper 60s to low 70s and lows
will be in the mid 50s. Fog is expected to develop in the late night
and early morning hours in our eastern zones where cloud coverage
will be light enough for it to develop.

Short term [sunday through Monday night]...

The shortwave over Texas at the beginning of the period will
dampen out as it moves eastward into the central Gulf Coast
region by Sunday night. The associated cold front will sweep
through the local area Sunday night through Monday bringing with
chances for showers and isolated thunderstorms. Quantitative precipitation forecast with this
system should generally be around one-half inch or less with a few
locations possibly reaching one inch, mainly over the western
zones. Temps will be be above seasonal levels with highs in the
70s and lows Sunday night in the lower 60s.

Long term [tuesday through saturday]...

The upper level pattern will be nearly zonal through Wednesday
night followed by backing flow to the southwest as a deepening low
pressure system develops in the Southern Plains and begins to
advance eastward. This will bring the next cold front and chances
for rain to the region by the end of the work week into the first
part of next weekend. Temps will be near or just below seasonal
levels.

&&

Aviation...

[through 18z sunday] VFR is expected to prevail through the first 12
hours or so of the period. However...as a cold front approaches our
area...MVFR-IFR cigs are expected to develop across the area with
reduced vsbys possible as well. A brief shower or two near dhn and
ecp cannot be ruled out either.

&&

Marine...

Light to moderate winds and low seas are expected to prevail
through at least the middle of next week. Winds will be onshore
through Sunday night and veer to become offshore by late Monday
as a weak cold front pushes through the waters. Offshore flow
will continue until late in the week before they swing around to
become onshore again ahead of the next approaching cold front.

&&

Fire weather...

Atmospheric conditions will remain too humid to allow any fire
weather concerns over the next week. Dispersion indices will be on
the low side on Sunday, near 30 in some areas. Even lower dispersion
indices are forecast for Monday, with areas north and west of
Tallahassee peaking well below 30.

&&

Hydrology...

Current River data this afternoon shows that the crest wave in the
Ochlockonee has passed the Havana gage and is discharging into the
upper end of Lake Talquin. Flows above Concord are in recession,
though it will take some time before water levels at Concord drop
enough to lessen impacts in the northern portion of Leon County.
Inflows into Lake Talquin and operations at Jackson Bluff will
result in rises at Bloxham to near flood stage today, though with a
slightly lower crest at Havana today, Bloxham should stay just below
flood stage. However, with 21000cfs discharging downstream, rises at
Smith Creek to minor flood stage are likely by Monday.

In the Withlacoochee system - both Hahira on the Little River side
and skipper bridge on the Withlacoochee side have crested. Combined
flow between these two sources is around 35000cfs. Due to a
variety of factors, a reduction of this combined flow by 15 percent
historically has produced a decent prediction for the US-84 gage.
This suggests a crest in the 28.5 to 29 foot range late Sunday
night. While the timing of the crest wave through the system is
matching up with recent flood events, the rate of rise at US-84 is
outpacing expected trends. Thus it looks like there's an increased
chance to hit major flood stage there by Sunday night. These
conditions suggest that the Withlacoochee at Pinetta will continue
rising through action stage into the coming week and potentially
exceed flood stage after the first of the year.

Elsewhere in the Hydro area, releases from Woodruff will keep the
Apalachicola at Blountstown above flood stage for the next couple of
days.

The Choctawhatchee River at Caryville has already crested and with
the flood wave moving downstream receiving minor contributions from
Bruce creek and Holmes creek along the way, Bruce should easily rise
above flood stage late tomorrow. There is some potential for
moderate flood stage to be met at Bruce by Tuesday morning.

Our next system will deliver another chance of 1 to 2 inches of rain
starting Sunday night and continuing through Monday night. With this
rain spread over a 24 to 36 hour period, limited impact is expected
on existing river levels. A short period of quiet weather is
expected throughout the remainder of the week before a stronger
storm system approaches the area next Saturday. With little
opportunity to dry out from the recent heavy rains, the flood
potential will remain elevated across the region with river flows
now well above normal.

For the most up to date information, please visit:
http://www.Water.Gov/ahps2/index.Php?Wfo=tae

&&

Preliminary point temps/pops...

Tallahassee 55 77 62 75 54 / 10 10 50 50 20
Panama City 59 75 63 71 54 / 20 20 60 30 10
Dothan 56 76 60 71 48 / 40 30 70 40 10
Albany 53 77 61 73 50 / 20 10 60 50 10
Valdosta 56 77 61 76 55 / 10 10 30 50 30
Cross City 57 78 62 77 60 / 10 10 20 40 30
Apalachicola 59 73 63 72 57 / 10 10 50 40 10

&&

Tae watches/warnings/advisories...

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

&&

$$

Near term...Moore
short term...Barry
long term...Barry
aviation...Moore
marine...Barry
fire weather...Moore
hydrology...Godsey

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