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Area forecast discussion 
National Weather Service Mobile Alabama
609 PM CST Friday Feb 12 2016

Discussion...updated for latest aviation discussion below.

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Aviation...
13/00z issuance...VFR conditions expected through the period with no
restrictions to surface visibility. A few middle level clouds very early
this evening as a frontal boundary moves south across the
region...otherwise mostly clear to clear skies expected. A mostly
light northerly flow expected tonight...increasing to light to
moderate tomorrow. 12/ds

&&

Previous discussion... /issued 412 PM CST Friday Feb 12 2016/

Near term /now through Saturday/...upper trough mostly to the east
near the eastern Seaboard will continue to shift eastward followed
by a strong 1040 surface high moving southward over the north Central
Plains...prognosticated to shift more east overnight and during the day on
Sat...stretching southward across central Gulf states and northern
Gulf waters through Sat afternoon. A moderate to strong cold front
ahead of this system is still prognosticated to move southward across the
forecast area early tonight giving way to more seasonal temperatures
overnight and during the day on Sat. Gusty northerly winds in the
wake of the front will also lead to wind chill values from the lower
to middle 30s for most areas a few hours before sunrise continuing
through about 8 am. For Sat...expect mostly sunny skies with brisk
northerly winds in the morning diminishing through the late morning
and the afternoon hours.

As for temperatures will lean towards the warmer mav numbers for tonight
due to good mixing in the boundary layer and the cooler mav
guidance on Sat due to the continued flow from the north. 32/ee

Short term /Saturday night through Monday night/...high pressure
axis moves across the Appalachians Saturday night. A cold
night on tap Saturday night as dry air...coupled with light wind and
clear skies supports effective radiational cooling processes with low
temperatures dipping down in the upper half of the 20s interior to
the middle 30s closer to the coast. High pressure begins to lift northeast
from the del marva to the New England states Sunday. As this
occurs...a return flow sets up...bringing a gradual moderation in
daytime highs.

Heading into Sunday night...next upper level storm system/trough is
prognosticated to drop southeast across the plains...pivoting across the
lower Mississippi River Delta Monday. Height falls associated with
the high level trough causes a wave of frontal low pressure to evolve
and track east across East Texas...approaching the central Gulf Coast
on Monday along with an attendant cold front. With the approach of
this system and large scale ascent...forecasters maintain the highest
probabilities of precipitation (pops) during the day
Monday...shifting eastward Monday night with probability of precipitation trending lowering
after midnight. Given the steady eastward progression...the window of
opportunity/duration is short for higher deep layer moisture to
become available. Thus...the forecast only calls for precipitable
water values to lift up to around 1.25" by Monday afternoon. As far
as storms...south to southwest 850 millibar low level jet increases
to 40 to 45 knots on average between the operational GFS/ECMWF...but
limiting factors for coverage of strong to severe storms continues to
be low instability with most unstable energy less than 300 j/kg and
marginal deep layer moisture at best. Considering this...forecasters
keep the risk of severe weather low for Monday and Monday night. Will
continue to monitor.

Long term /Tuesday through Friday/...rain-free weather forecast
during the outlook as high pressure moving east across the local
area. Highs in the low/middle 60s Tuesday moderate through the week into
the upper 60s/lower 70s by Friday. Lows also moderate through the
week. Lower/Middle 40s Tuesday night...into the Lower/Middle 50s by Friday
night. /10

Marine...a moderate westerly flow will continue through this
afternoon ahead of an approaching cold front from the northwest.
The front is expected to move south across the marine area early
tonight leading to a moderate to strong offshore flow late tonight
through early Sat. Winds will increase to 15 to 20 knots with
frequent higher gusts for the near shore waters out to 20 nm and 18
to 23 knots with frequent higher gusts well offshore. Seas up to 6
feet well offshore will also be likely. A Small Craft Advisory is in
effect for the offshore legs of Alabama and nwfl from midnight tonight
through 8 am Sat morning. Northerly winds will shift northeast then
east and slowly diminish through early sun followed by a light to
moderate southerly flow late sun through Monday in advance of the next
cold front. A strong offshore flow is expected in the wake of the
front late Monday through Tuesday. Small craft advisories will likely be
required in the wake of the front through midweek. 32/ee

&&

Mob watches/warnings/advisories...
Alabama...none.
Florida...none.
MS...none.
GM...Small Craft Advisory from midnight tonight to 9 am CST Saturday
for gmz670-675.

&&

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