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Area forecast discussion...updated 
National Weather Service Mobile Alabama
1253 PM CDT Sat Oct 1 2016

Discussion...updated for latest aviation discussion below.

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Aviation...
18z issuance...VFR conditions will persist through the weekend along
with light and variable winds. /22

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Previous discussion... /issued 440 am CDT Sat Oct 1 2016/

Near term /now through Saturday night/...an upper low over the Ohio
River valley meanders northeast to over the eastern Great Lakes,
allowing a surface ridge to begin organizing over the Mississippi
River valley. This helps to re-enforce the dry northerly flow over
the southeast, especially over eastern parts of the fa and just east.

For the forecast, with moisture lacking, no precip is pretty much a
given. As for temps, the retreating upper system leaves an upper
trough stretching south across the lower Mississippi River valley,
keeping an upper ridge over the western Atlantic from expanding west
over the southeast. With the upper trough keeping subsidence from
the Atlantic upper high from reaching the fa, in combination with
dry airmass will create a diurnal temp range greater than average,
today's highs are expected to be above seasonal, ranging from the
low to mid 80s. Tonight's lows are expected to be a bit below
seasonal, ranging from the low 50s to around 60 closer to the coast,
mid 60s along the coast. /16

Short term /Sunday through Monday night/...the upper level low will
continue to lift northeast from the Ohio Valley and Great Lakes
toward the New England states Sunday through Monday. Shortwave
troughing will meanwhile extend from the Ohio and Tennessee Valley
region and southwestward to the central Gulf Coast through Monday.
Deep layer moisture will remain limited across our forecast area
through Monday on the base of the trough axis, so we will continue to
maintain a dry forecast. A weak surface ridge of high pressure will
otherwise extend southward across our forecast area through Monday,
keeping a dry surface airmass in place. High temperatures Sunday will
mostly range in the mid 80s, warming slightly to the upper 80s to
around 90 inland by Monday. Lows Sunday and Monday nights should
continue to range from the upper 50s to lower 60s over most interior
locations, and in the mid 60s to around 70 along the immediate coast
and beaches. /21

Long term /Tuesday through Friday/...weak shortwave ridging will
extend across our region Tuesday into Wednesday. Hurricane Matthew is
forecast to track northward from near eastern Cuba Tuesday toward the
Bahamas Wednesday into Thursday. No direct local impacts are
expected from Matthew. A deep layer dry airmass will remain in place
Tuesday, with continued warm and dry conditions expected. A slight
increase in moisture may be possible near the immediate coast by
Wednesday, where an isolated shower cannot be ruled out, but dry
weather should otherwise prevail across the region. An upper level
trough may translate from the central Continental U.S. To the upper Midwest
during the middle to latter half of the week, and an associated
frontal boundary may approach the Mississippi Valley region Thursday,
and possibly the central Gulf Coast by Friday. Medium range model
solutions continue to show little in the way of moisture available
along and ahead of the front, with only the European model (ecmwf) showing perhaps
enough moisture for an isolated shower or storm over southeast MS by
Thursday. We will continue to keep a mostly dry forecast through late
in the extended period. Temperatures should trend back to slightly
above normal readings Tuesday through Friday, with highs mostly
ranging from the mid 80s to around 90 degrees each day, with lows
trending back up into the mid to upper 60s inland and in the lower
70s near the beaches by late next week. /21

Marine...a weak surface ridge will develop over the Mississippi
River through the weekend, creating a general light northerly flow
over area coastal waters. A daily Gulf Breeze is expected to develop
and move inland, creating a temporary light onshore flow along the
coast. As Matthew moves north from the Caribbean along the Florida
Atlantic coast the first half of the coming week, a temporary switch
to a general easterly tueday through Wednesday occurs, but by
Thursday, a general northeasterly flow returns to area coastal
waters. /16

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Mob watches/warnings/advisories...
Alabama...none.
Florida...none.
MS...none.
GM...none.
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