Flood in Florida, May 2 to 3, 2014

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TALLAHASSEE FL
926 PM EDT Thu May 1 2014

.Near Term [Through Tonight]...

A large area of low pressure aloft continues to cover much of the
country this evening. As of 00Z the low was centered over the
Great Lakes region, with its axis extending southwest through the
Southern Plains. At the surface, a very slow moving if not
stationary front extends down the eastern U.S. coastline from the
Mid-Atlantic region, exiting north Florida around the mouth of the
Suwannee, and draped southwest through the north-central Gulf. The
latest IR/WV imagery sheds light on a southern stream anomaly
moving northeast across the extreme northern Gulf, near the
Louisiana coastline. Linear extrapolation of this feature would
bring it near north Florida around 06z tonight. As it approaches,
expect another rain shield to develop essentially area-wide.
Rainfall amounts are not expected to be high, and should remain
around a quarter of an inch to a half of an inch. The cold front
will likely remain out ahead of this upper level disturbance,
though should a weak area of mesoscale low pressure currently
centered over the southeast Big Bend link up with the disturbance
and subsequently be pulled a bit northwest, there could be some
more focused convection along the front.

&&

.Aviation...
[Through 00Z Saturday]...

VFR conditions will persist through much of the night, but will
begin to give away to MVFR ceilings from south to north as another
round of rain begins between 06-12z. DHN and ABY are not expected
to drop below VFR ceilings through the period. However, the MVFR
may last until late afternoon and ECP and TLH and to the end of
the period at VLD.

&&

.Prev Discussion [358 PM EDT]...

.Short Term [Friday Through Saturday Night]...

Expect one more day of rain before the pattern begins to shift and
the region finally gets a few days to dry out. Model guidance is
in relatively good agreement that as an approaching upper trough
digs into the Mid South, that another area of rain will develop
over the northeastern Gulf and move into the Florida Big Bend.
With increasing confidence in the placement of the rain on Friday
from the global models and the hi-res output, will indicate
categorical pops across the southeastern half of the forecast
area. The airmass in place by Friday will have modified quite a
bit and not be nearly as tropical as it was earlier this week. As
a result, rainfall rates and associated rainfall totals should not
be especially significant. Rainfall amounts of 2 to 3 inches will
be possible across the Southeast Florida Big Bend with lesser
amounts further to the north and west. Essentially, this rain will
be occurring across an area that hasn't seen a lot of rainfall
this week, so there isn't a concern for widespread flooding at
this time.

By Saturday as the trough amplifies and moves eastward across the
Southeast, the bulk of the moisture will be pushed south and
eastward out of the region as even drier air arrives from the
northwest. Expect clearing skies by afternoon with temperatures
warming back to the lower 80s.

.Long Term [Sunday Through Thursday]...

The long term period will be dominated by a large high pressure
area across the region at the surface. Mid level ridging will also
build in by the middle of the week. As a result, expect dry
conditions through the long term period with temperatures warming
above climatology by Monday. In fact, the potential exists for
some lower 90s across the interior areas by the middle of the
week.

.Marine...

Winds have diminished below headline criteria. While a slight
increase is anticipated overnight, do not expect cautionary
criteria to be met. By Saturday evening, high pressure will build
over the marine area and remain in place well into next week,
resulting in an extended period of light winds and low seas.

.Fire Weather...

Low-level moisture will remain abundant through Friday before a
much drier airmass moves in for the weekend. Despite much lower RH
values on Saturday, moist soil conditions will prevent any red
flag concerns.

.Hydrology...

Rainfall rates and accumulations over the last 24 hours have been
on the low side and have had little additional impact on areas
that are still experiencing flooding. Most river locations (aside
from the flashier creeks) are working toward crests that will
occur late this weekend or early next week. Primary concerns in
the Panhandle are the Choctawhatchee River which will reach major
flood levels again at Bruce. The Chipola River at Altha is already
above moderate flood levels and will move toward a crest this
weekend around 27.7 feet, which would be a top 9 crest.

Over in the Suwannee, crests have occurred through Luraville. So
expect the Suwannee upstream of Luraville to continue to recede
through the weekend as the incoming rainfall will have little or
no impact on river levels. Further downstream from Branford
through Fowlers Bluff, expect water levels to continue to rise,
though Branford should crest on Friday. Biggest concern downstream
of Branford is whether there's enough water in the system to reach
moderate flood levels at Wilcox and move toward 7 feet at Fowlers
Bluff. The current thinking at this time is that we'll come up
just short of moderate flood at Wilcox, though an eventual crest
in 4 days or so near 13.5-13.7 feet is certainly possible. Fowlers
Bluff is still about 6-7 days away from cresting somewhere just
below 7 feet.

&&

.Preliminary Point Temps/PoPs...

Tallahassee   57  66  49  81  54 /  70  80  40  10   0
Panama City   58  65  57  77  64 /  70  80  20  10   0
Dothan        53  73  52  82  56 /  70  50  10   0   0
Albany        55  71  52  82  55 /  70  60  20  10   0
Valdosta      57  68  51  78  53 /  70  90  50  10   0
Cross City    63  75  56  78  52 /  50 100  80  30   0
Apalachicola  59  66  55  76  61 /  70  80  40  10   0

&&

.TAE Watches/Warnings/Advisories...

FL...High Rip Current Risk until 1 AM EDT /Midnight CDT/ Friday for
     Coastal Bay-Coastal Gulf-South Walton.

GA...None.
AL...None.
GM...None.

&&

NEAR TERM...HARRIGAN
SHORT TERM...GODSEY
LONG TERM...GODSEY
AVIATION...WOOL
MARINE...GODSEY
FIRE WEATHER...CAMP
HYDROLOGY...GODSEY