Area Forecast Discussion
Issued by NWS

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
127
FXUS62 KTAE 180118
AFDTAE

Area Forecast Discussion
National Weather Service Tallahassee FL
918 PM EDT Wed Oct 17 2018

.UPDATE...

The cold front is currently along a line north of Tallahassee from
Valdosta to Panama City. There are a few light showers along the
front, so increased PoPs slightly for north Florida. Otherwise
forecast remains on track with lows in the low 60s in southeast
Alabama to low 70s in the Big Bend.

&&

.PREV DISCUSSION [726 PM EDT]...

.NEAR TERM [Through Tonight]...

A stationary front remains stretched from southwest Georgia
southwestward into the coastal counties of the Emerald Coast this
afternoon. This front should make some progress southward tonight in
response to a shortwave disturbance digging through the base of the
upper level trough over the Northeast U.S. Limited moisture and
instability associated with the front should keep pops below
mentionable levels overnight. A drier and cooler airmass should
filter into the northern half of the forecast area with lows
dropping into the lower to middle 60s along and north of a line from
Panama City, FL, to Valdosta, GA. Dewpoints will also drop well into
the 50s, with even some upper 40s dewpoints into southeast Alabama
and portions of southwest Georgia. Further south towards the coastal
counties of the Florida Big Bend, expect dewpoints to remain well
into the 60s with lows in the lower 70s, to the south of the front.

The potential for low level stratus and fog looks much lower tonight
as the shallow isentropic ascent over the shallow frontal slope
significantly weakens as compared to the previous two nights.


.SHORT TERM [Thursday Through Friday Night]...

The front will sharpen and advance through the coastal Florida Big
Bend on Thursday. Only expecting isolated showers with the front as
lift remains weak overall. Pre-frontal instability appears limited
which should preclude thunder chances. High temperatures in coastal
areas will reach into the middle 80s before the front pushes through
during the afternoon. Further north across southeast Alabama and
southwest Georgia, high temperatures will struggle to reach 80
degrees along with much lower humidity.

The front pushes well south of the coast by Thursday evening with
cooler and less humid conditions advecting into coastal areas. Gusty
northeast winds along the beaches will be possible Thursday night as
the sharpening temperature gradient between the cooler land surfaces
and warmer marine areas tightens the pressure gradient. Low
temperatures will drop to near 60 degrees across southeast Alabama
and southwest Georgia, to the middle and upper 60s right along the
coast where the boundary layer will remain well mixed.

High pressure will settle over the region on Friday and Friday night
with dry and seasonably cool temperatures expected along with low
humidity levels. High temperatures Friday will be in the lower to
middle 80s with lows Friday night in the middle to upper 60s.


.LONG TERM [Saturday Through Wednesday]...

A major shortwave trough is expected to drive a southward moving
cold front across the forecast area Saturday afternoon. The deep
layer moisture along this boundary coupled with the projected strong
low to mid level forcing should prove ample enough to support a
good chance of showers and possibly isolated thunderstorm activity
though instability will be limited. This system will be fast
moving and rainfall totals are expected to remain less than half
an inch at this time. Drier and cooler air will follow in the
fronts wake with breezy northerly winds developing Saturday night
along the coast as the front moves southward over the Gulf of
Mexico. By Sunday night, overnight lows are expected to fall into
the 50s near the coast and into the mid 40s at more interior
locations with daytime highs on Sunday only climbing into the low
to mid 70s. Temperatures begin to warm Monday night or Tuesday as
the surface high pressure which had dominated the local weather
moves off the east coast over the Atlantic and a moist east to
southeasterly return flow develops over the region. Upstream
another major shortwave trough moving southward out of southern
Canada is driving another cold front lying across the Midwestern
states southward that may pass through the area late Wednesday or
later.


.AVIATION [Through 00Z Friday]...

VFR conditions are expected to prevail through the period.


.MARINE...

Winds and seas will increase later tonight as the pressure gradient
tightens between a building surface high over the Midwest and a weak
frontal boundary along the northern Gulf Coast. Hazardous conditions
for small craft will develop overnight before seas and winds
gradually diminish on Thursday morning. Seas and winds will again
increase Thursday night with hazardous conditions once again
possible for small craft.

Winds and seas briefly diminish Friday into early Saturday. A strong
cold front will move across the coastal waters Saturday evening.
This will result in an abrupt increase in winds and seas with small
craft advisory conditions likely developing through Sunday into
early next week.


.FIRE WEATHER...

Dispersion indices tomorrow afternoon are expected to range from Fair
to Generally Good but fall into the Poor to Generally Poor
categories on Friday afternoon.  Otherwise no additional fire weather
concerns. Fog is not expected through Thursday night, with patchy
fog possible Friday night and early Saturday morning.


.HYDROLOGY...

The Chipola River at Altha is currently in action stage with a stage
of 21.1 feet. The Chipola River at Altha is forecast to rise to
minor flood stage early tomorrow morning and is expected to crest
near 22.4 feet by Thursday afternoon. The river will remain in
minor flood stage through Friday afternoon. The flood warning is
currently in effect through late Friday evening.


.SPOTTER INFORMATION STATEMENT...

Spotter activation is not requested. However, spotters are always
encouraged to safely report significant weather conditions when they
occur by calling the office or tweeting us @NWSTallahassee.

&&

.PRELIMINARY POINT TEMPS/POPS...

Tallahassee   66  85  64  85  68 /  20  10  10  10  10
Panama City   67  84  65  85  69 /  20  10  10  10  20
Dothan        62  80  61  81  65 /  10   0  10  10  10
Albany        64  80  61  80  66 /  10   0  10  10  10
Valdosta      66  85  63  83  66 /  10   0  10  10  10
Cross City    71  86  69  87  70 /  20  30  10  20  20
Apalachicola  69  83  69  84  71 /  20  10  10  10  20

&&

.TAE WATCHES/WARNINGS/ADVISORIES...
FL...None.
GA...None.
AL...None.
GM...None.
&&

$$

UPDATE...Weston
NEAR TERM...Howell
SHORT TERM...Howell
LONG TERM...Werner
AVIATION...DVD
MARINE...Howell
FIRE WEATHER...Werner
HYDROLOGY...Johnson



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.