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Area forecast discussion...updated 
National Weather Service Mobile Alabama
602 am CST Tue Dec 6 2016

Discussion...see updated information for marine areas and aviation
discussion below.


Marine...area marine observations indicate that westerly flow is
increasing following passage of the cold front early this morning,
and we have included all marine zones including bays and sounds in
the Small Craft Advisory until noon CST. Wind speeds of 20-25 knots
are generally expected over the bays and sounds, and 25-30 knots with
occasional gusts approaching gale force offshore. Winds should
diminish this afternoon with direction turning northwesterly. /21


12z issuance...cold front will quickly sweep from west to east across
the area this morning, with winds turning westerly and increasing to
10-15 knots, with a few gusts over 20 knots through the morning
hours. Winds should turn northwesterly and decrease in speed this
afternoon. Localized IFR to LIFR cigs and patchy fog over far eastern
portions of the area can be expected prior to frontal passage, but
MVFR cigs otherwise look to persist across most of the area through
the period. /21


Previous discussion... /issued 434 am CST Tue Dec 6 2016/

Near term /now through Tuesday night/...a shortwave trough is
ejecting across the lower Mississippi Valley early this morning,
while an associated area of surface low pressure is lifting into
northern MS. An attendant cold front extends southward from the
surface low and is progressing eastward across central portions of
MS and far southeastern la. Water vapor imagery shows a dry slot
moving from MS into western Alabama this morning, while deep layer
moisture and lift is pushing to the east of our area. The line of
convection has subsequently moved well to the east of our area as of
4 am...with radar only showing a few isolated showers lingering over
interior south central Alabama.

The cold front will quickly move from west to east across our
forecast area early this morning, with winds turning westerly (gusty
at times early this morning) in its wake. The dry slot will end rain
chances across the region early this morning and no more
precipitation is expected through tonight. Low cloud cover may
linger across the area through the day, especially over interior
areas, so have opted to trend high temperatures toward the cooler
guidance today. Highs could struggle to reach 60 over interior
southeast MS and southwest al, but should otherwise range from the
lower to mid 60s northwest of I-65 and in the upper 60s to near 70
over the southeastern part of the area. Cooler temperatures are
expected tonight as surface high pressure builds into the region.
Lows should range from the mid to upper 40s over much of the
interior to the lower 50s near the immediate coast. /21

Short term /Wednesday through Thursday night/...Wednesday will be the
last day in the 60s until next week as a strong Arctic front dives
southward toward the area. Highs on Wednesday will range from the
low 60s inland to mid 60s near the coast. A strong trough over the
Great Lakes will move to the East Coast by Friday morning. Ahead of
the trough, the first Arctic front of the season will move south across
the area on Thursday. This will lead to steady temps in the morning,
followed by falling temps in the wake of the front during the
afternoon hours as a much colder and drier airmass flows into the
area. We will maintain small rain chances on Thursday as the strong
cold advection will serve to squeeze the limited moisture out as
light rain showers.

Lows Thursday night will fall into the upper 20s inland to mid 30s near
the coast. Strong northerly winds will make it feel even colder with
wind chills possibly dropping into the upper teens across far northern
areas by Friday morning. /13

Long term /Friday through Monday/...Friday and Friday night will be
the coldest of the period as Arctic high pressure settles over
the southeast. Highs on Friday will not get out of the 40s across
much of the area. Lows Friday night will fall into the low to mid
20s inland to upper 20s and low 30s across southern areas. The
high quickly shifts east over the weekend, allowing a return flow
to develop by late in the weekend. This will result in temperatures
quickly moderating back to slightly above normal levels on
Monday. With low level flow/warm air advection increasing Sunday and
Monday ahead of a fast moving shortwave over the central conus,
there will be the potential for isolated to scattered showers across
the area. /13

Marine...strong westerly winds will impact the marine area this
morning following the passage of a cold front, with speeds ranging
from 15-20 knots over most protected waters (except 20-25 knots over
Mobile Bay/MS sound) and as high as 25-30 knots with a few gusts
nearing gale force offshore. Seas as high as 7-9 feet offshore this
morning should gradually subside this afternoon into tonight. A
Small Craft Advisory continues over these areas this morning. Wind
speeds should gradually weaken as the gradient relaxes this
afternoon with direction turning more northwesterly this afternoon
into this evening. A reinforcing cold front will bring a return to
strong offshore flow Thursday into Friday. /21


Mob watches/warnings/advisories...
Alabama...high rip current risk through this afternoon for alz265-266.

Florida...high rip current risk through this afternoon for flz202-204-206.

GM...Small Craft Advisory until noon CST today for gmz633>635.

Small Craft Advisory until noon CST today for gmz630>632-650-655-



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