Area Forecast Discussion
Issued by NWS
FXUS62 KTAE 160725
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TALLAHASSEE FL
325 AM EDT Wed Apr 16 2014
.Near Term [Through Today]...
A broad long wave trough will remain in place across much of North
America today with our area transitioning to southwest flow aloft.
At the surface, high pressure over the Ohio Valley will shift
northeastward to New England, but will continue to ridge southward
to the Gulf Coast. After a chilly start this morning, temps will
rebound quickly under mostly sunny skies. Highs will be in the upper
60s in most areas with some lower 70s expected across southern
portions of the FL Big Bend.
.Short Term [Tonight Through Friday]...
The short range period begins with a broad full CONUS 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 FL 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
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 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 CWA
but it appears there will only be a slight chance of rain with
[Through 06Z Thursday]
VFR conditions will persist through the period. NNW winds will
gradually veer to the northeast overnight and remain sustained at
6-10 kt. ENE winds will prevail after about 14z. Wind gusts will
not be as high as on Tuesday.
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.
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. RH will increase
quickly after today with another round of wetting rain expected on
Heavy rains across the FL 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
GM...Small Craft Advisory until 2 PM EDT this afternoon for Apalachee
Bay-Coastal waters From Ochlockonee River to Apalachicola
FL out to 20 NM-Coastal waters from Suwannee River to
Keaton Beach FL out 20 NM-Coastal waters from Apalachicola
to Destin FL out 20 NM-Waters from Suwannee River to
Apalachicola FL from 20 to 60 NM-Waters from Apalachicola
to Destin FL from 20 to 60 NM.