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Area forecast discussion...update to aviation and short term 
National Weather Service Mobile Alabama
440 PM CST Tuesday Mar 3 2015

Aviation...
06z terminal forecast discussion...am expecting IFR or low ceilings and visbys
over coastal counties and nearby areas overnight. With cool coastal waters...
guidance is pretty consistent in advertising a high probability od dense fog
developing again tonight. Inland...ceilings look to be the main problem...
with MVFR to IFR levels overnight. Am expecting ceilings/visbys to rise
with daytime heating Wednesday...but guidance is hinting at another dense fog
event again Wednesday night.

/16

&&

Update...no update to current package...with everything generally on track.

/16

&&

Short term [tonight through Wednesday night]...a southwest flow
aloft will persist across the region through the next 24 hours
between an upper level ridge of high pressure building from the
southeastern Gulf of Mexico to the western Atlantic Ocean and a
deepening trough over the Rocky Mountains and Desert Southwest. A
surface ridge of high pressure extends over the southeastern states
and the northern Gulf of Mexico. Visible satellite imagery shows some
residual low clouds across the region though some locations have
broken out in sunshine. Some patchy fog was still noted along the
immediate coast of the northwest Florida Panhandle. Temperatures have
warmed into the 70s over most inland locations...though middle to upper
60s were common near the coast.

A surface ridge of high pressure will continue to extend from the western
Atlantic to the north central Gulf of Mexico tonight. The latest hrrr/rap
models are in agreement that fog will develop mainly over coastal portions of
the County warning forecast area early this evening before spreading northward across much of the rest
of the County warning forecast area through the overnight and early Wednesday morning hours. Confidence
in dense fog potential is highest along coastal portions of the forecast area
where we will issue a dense fog advisory from early this evening through
Wednesday morning. Later shifts will monitor fog development and expand
northward if necessary. Weak isentropic lift could support light drizzle or
light rain primarily over northwestern portions of the County warning forecast area. Will go with
mention of no rain across the rest of the area tonight. A mild night is
expected with lows ranging in the upper 50s to the lower 60s.

A warm and moist southerly flow pattern will persist Wednesday as the surface
ridge axis remains oriented from the western Atlantic to the northeastern Gulf
and ahead of a strong cold front approaching the Tennessee and lower
Mississippi Valley region. Areas of fog should gradually diminish
with temperatures looking to warm into the middle to upper 70s by the
afternoon. Weak isentropic lift will support a slight to low chance
of rain across the region Wednesday. /21

Wednesday night...a cold front...the leading edge of a colder
airmass...surges southeast approaching the I-65 corridor by daybreak
Thursday morning. Southeast of the front...showers will be likely. A
few rumbles of thunder possible as well. Northwest of the
front...temperatures undergo a sharp decline. This brings about some
potential interesting developments with regard to wintry weather. The
forecast temperature profiles are forecast to trend below freezing in
the lowest couple thousand feet in the presence of northerly flow
and cold air advection processes. Above this layer...a substantial
warm layer exists with flow from the southwest. Thus...the risk
favors light freezing rain along and northwest of a line from
Waynesboro MS to Butler Alabama by daybreak Thursday. At this time...the
impacts look limited with light icing on bridges/overpasses possible over
these areas.

The warmer lows range from 55 to 60 along the western Florida
Panhandle coast...before trending colder during the day Thursday.
There remains quite a bit of uncertainty in this forecast on timing
the progression of the colder air.

Long term [thursday through tuesday]...cold front surges southward
into the Gulf on Thursday...with good cold air advection bringing a
chilly day. With clouds...rain...and lowering thickness
values...temperatures will be a challenge for Thursday. Daily highs
over most areas in the am...then falling through the day...taking on
a non-diurnal daily curve. Highs hard pressed to get out of the middle
30s Thursday over the interior northwest...falling through the 40s
over the I-65 corridor and into the lower 50s over the western
Florida Panhandle. A cold rain is forecast to track east southeast
and out of the area by Thursday evening. Overnight lows Thursday
night in the middle/upper 20s northwest of I-65 to middle/upper 30s over
the western Florida Panhandle.

It will be cool through the remainder of the extended forecast in
the wake of the cold front and with a broad upper trough remainder
over the eastern Continental U.S.. while it will be dry on Friday...isolated to
scattered rains re-enter the picture for the weekend into the first
of next week as a series of weak upper disturbances and shortwaves
exit the Southern Plains states and traverse the region.

High temperatures will only reach the upper 40s to middle 50s on Friday
and then steadily climb into the lower 60s by Monday. Low
temperatures Friday night will be in the middle 30s to middle 40s and
mostly be in the Lower/Middle 40s Sunday through Tuesday mornings over
the interior. Exception being the upper 40s/lower 50s along the
immediate coastal sections. /22

&&

Marine...area beach/marine cameras indicate some dense fog
lingering near the immediate coast this afternoon...and expect dense
fog to become widespread this evening through early Wednesday
morning. A dense marine fog advisory will remain in effect until 9
am Wednesday.

A light to moderate southeast to south wind flow will otherwise continue over
the marine area through Wednesday evening ahead of a strong cold front
approaching from the northwest. The cold front is expected to move across the
northern Gulf Thursday morning...with strong offshore flow over the marine area
Thursday through early Friday. Northerly winds and seas will gradually diminish
late Friday through Saturday as a broad surface ridge builds to the north. A
Small Craft Advisory will be likely on Thursday in the wake of the strong cold
front. 32/21

&&

Preliminary point temps/pops...
Mobile 61 76 47 48 31 / 10 30 60 70 10
Pensacola 60 75 56 58 35 / 10 20 50 70 10
Destin 60 71 60 62 39 / 10 20 40 70 10
Evergreen 60 77 48 51 31 / 10 30 70 70 10
Waynesboro 61 76 33 36 27 / 20 40 80 70 10
Camden 61 76 42 44 29 / 10 30 80 70 10
Crestview 60 76 58 60 35 / 10 20 50 70 10

&&

Mob watches/warnings/advisories...
Alabama...dense fog advisory from 7 PM this evening to 9 am CST Wednesday
for alz063-064.

Florida...dense fog advisory from 7 PM this evening to 9 am CST Wednesday
for flz002-004-006.

MS...none.
GM...dense fog advisory until 9 am CST Wednesday for gmz630>635-650-
655.

&&

$$

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