Rip Current Statement 53, NWS Tallahassee, FL

Area Forecast Discussion
National Weather Service Tallahassee FL
1107 AM EDT Fri May 12 2017

.UPDATE...

Increased chances of showers and thunderstorms across our
northwestern areas this afternoon and early evening as latest CAM
runs have come into better agreement on a cluster of storms
moving eastward into southeast AL and inland FL Panhandle
locations starting around 18-19Z. With SBCAPE values increasing to
1500-2000 J/kg and effective bulk shear around 30-40 kts during
this time, a few of the storms could become strong to severe in
these areas with hail and damaging winds being the main threats.

Otherwise, the current forecast looks to be on track, and only
minor adjustments were made through tonight. The highest chance
of rainfall across most of our area, as showers and thunderstorms
will be likely during this time along/ahead of a cold front. A
marginal risk of severe weather will remain present through this
time with hail and damaging winds possible in the strongest
thunderstorms.

&&

.PREV DISCUSSION [655 AM EDT]...

.NEAR TERM [Through Today]...

A closed upper low over Oklahoma early this morning will translate
east southeastward into northern Mississippi this evening. At that
time, the associated cold front will extend southwestward from a
low over central Mississippi to the western Gulf. Showers and
thunderstorms ahead of the front are expected to reach our western
zones by late afternoon or early evening. While a strong to
briefly severe thunderstorm is possible, the overall severe threat
is low at this time. Highs will be in the mid to upper 80s.

.SHORT TERM [Tonight Through Sunday]...

The aforementioned cold front will continue through the Tri-State
region overnight, with relatively high PoPs along its entire
journey. While the consensus is that deep layer shear will hover
around 40 knots, a rather weak LLJ and most importantly,
diminishing instability will limit the overall severe threat
with the line as it moves across the region. The SPC has kept the
northwestern third of our region (nw of a line from Albany through
Panama City) in a Marginal Risk through the overnight hours. On
Saturday, a residual surface trough will remain across the region
as what was the closed upper low moves slowly east as it remains
loosely attached to the northern stream flow. This will likely
result in at least some moisture transport around the back side of
the surface trough/low across the GA/SC line that will combine
with both the weak forcing from the trough and eventually a
secondary cold front late in the afternoon. The SPC has placed the
Suwannee Valley in a Marginal Risk for Saturday where afternoon
destabilization coincident with deep layer shear around 40 knots
could result in a few storms capable of producing damaging winds.
Showers and storms should come to an end region-wide by midnight
Saturday night with a dry and warm day expected on Sunday.

.LONG TERM [Sunday Night Through Friday]...

Deep layer ridging will prevail through next week, with highs
climbing into the 90s each afternoon.

.AVIATION [Through 12Z Saturday]...

Patchy fog has developed across the region this morning,
currently impacting the TLH terminal with LIFR cigs and vsbys.
Otherwise, mostly MVFR conditions at the remaining terminals. VFR
conditions should return by 15z as winds increase from the SW
ahead of an approaching cold front. There is a chance for showers
and TSTMs beginning this evening at DHN and spreading east to all
terminals by daybreak Saturday.

.MARINE...

Small craft operators should exercise caution beginning this
afternoon and lasting through Saturday as winds hover around 15 to
20 knots. Thereafter, winds and seas will be quite low for several
days.

.FIRE WEATHER...

Aside from high dispersion values Saturday afternoon there are no
fire weather concerns as moisture and rain chances increase the
next few days.

.HYDROLOGY...

Average rainfall amounts through Saturday look to total around
0.5"-0.75". Some isolated higher amounts could be possible across
parts of SW GA, SE AL, and the FL panhandle overnight, and
possibly across the SE Big Bend Saturday afternoon. Still, these
amounts ~1-2" would likely not result in any flooding issues.
Thus there are no hydrology concerns over the next several days.

&&

.PRELIMINARY POINT TEMPS/POPS...

Tallahassee   88  69  83  63  87 /  10  50  50  20   0
Panama City   79  72  79  68  81 /  20  60  30  10   0
Dothan        85  67  80  63  86 /  50  70  50  10   0
Albany        87  68  81  63  86 /  40  70  60  10   0
Valdosta      89  68  83  62  86 /   0  50  60  30   0
Cross City    86  68  80  65  88 /   0  50  50  20  10
Apalachicola  82  72  79  67  84 /  10  50  40  10   0

&&

.TAE WATCHES/WARNINGS/ADVISORIES...

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

&&

UPDATE...Lahr
NEAR TERM...Barry
SHORT TERM...Harrigan
LONG TERM...Harrigan
AVIATION...Barry
MARINE...Harrigan
FIRE WEATHER...Barry
HYDROLOGY...Harrigan