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Area forecast discussion 
National Weather Service Mobile Alabama
420 am CDT Thursday Oct 30 2014

Short term [today through Friday night]...middle to upper trough axis with
embedded short wave located near the MS/Alabama border this morning will
shift east of the County warning forecast area by late this afternoon allowing a deeper
layer of cooler drier air to advect southward over the central Gulf
region tonight and and early Friday. This pattern will lead to better
mixing in the boundary layer through tonight. To the northwest next
surge of much colder air begins to push down from Canada reaching
the Central Plains states by 12z Friday. As main short wave exits off
to the east later today and tonight a few middle to high clouds will
shift east across the region this evening and overnight with little
affect on night time temperatures. Otherwise...the main concern through
tonight will be much lower humidity values values across the region
by this afternoon followed by chilly temperatures overnight and early Friday
morning. As a result will lean towards the cooler met/mav MOS
guidance for highs today continuing with this trend for lows
overnight and early Friday morning due to the depth of cooler air
advecting southward. Highs today will range from the lower to middle
70s for most of the northern half of the forecast area and the
middle 70s to the south. Lows tonight will fall to the upper 30s to
around 40 to the north and east...north of the I-10 corridor...and
the middle 40s for areas to the west including the immediate coast.
32/ee

Dry northwest flow aloft will continue across our forecast area
Friday and Friday night between a deep upper trough diving from the
Great Lakes region toward the Ohio/Tennessee Valley and southeastern states
and an amplifying ridge over the central Continental U.S.. the next cold front
stretching across the Mississippi Valley region early Friday morning
will quickly move southeastward across the central Gulf Coast region
by Friday afternoon before pushing well offshore into the Gulf of
Mexico Friday night. Low precipitable water values of 0.4 to 0.6
inches will be in place across the area Friday...so no precipitation
is expected with this next front. The high temperature forecast
Friday will be a little tricky dependent on frontal timing. We
currently expect readings to range from around 70 to the lower 70s
over the northwestern half of the County warning forecast area to the middle 70s farther south
and east. A Cold Ridge of high pressure will settle across the
Mississippi Valley Friday night. Cold air advection will continue
Friday night with clear skies expected. Northerly surface winds will
remain elevated near the coast Friday night...but should decrease
over inland areas after midnight. We will continue to use a blend of
guidance for lows Friday night...looking for overnight readings to
range from the middle to upper 30s over interior portions of the
forecast area to the lower to middle 40s near the immediate coast. Some
patchy light frost will be possible over a few interior locations
late Friday night into early Saturday morning. /21

Long term [saturday through wednesday]...the deep upper trough will
move across the eastern Seaboard Saturday and into the adjacent
western Atlantic Saturday night into Sunday...while ridging aloft
builds eastward from the central U.S. Saturday toward the
Mississippi Valley region Sunday. A deep dry airmass will remain
intact across our forecast area...keeping rain chances none through
the weekend. A surface ridge of high pressure will continue to
stretch from the vicinity of the Great Lakes and southward through
the Mississippi Valley and northern Gulf of Mexico Saturday...keeping
cool temperatures in place across our forecast area. 925 mb
temperatures are still projected to range between 4-6 c across our
forecast area through Saturday afternoon...and high temperatures may
struggle to reach 60 over much of the forecast area. Mostly clear
skies...light winds...and a very dry surface airmass will promote
good radiational cooling Saturday night. We are expecting some of
the coldest readings so far this autumn season by early Sunday
morning. A few locations over the interior could experience the
first light freeze of the season...while patchy frost will be
possible elsewhere over much of our interior County warning forecast area. We expect lows
Sunday morning to range from the lower to middle 30s over much of the
interior to the upper 30s to lower 40s near the immediate coast. The
surface ridge axis will push eastward and will extend from the Ohio/Tennessee
Valley to the northern Gulf of Mexico by Sunday afternoon. Surface
flow should become more northeast to east across the County warning forecast area...and
temperatures should modify slightly into the middle to upper 60s.

Looking ahead into the extended forecast period...medium range
solutions are in good agreement with building an upper level ridge
of high pressure across the Gulf of Mexico Monday...with the ridge
axis stretching northward across our forecast area and into the
southeast states. The ridge axis becomes elongated from southwest to
northeast from the southwest Gulf of Mexico to the Florida Peninsula and
western Atlantic Tuesday and Wednesday as southwest flow aloft
increases from the northwest Gulf through the MS/Tennessee Valley region in
advance of the next deepening upper level trough over the vicinity
of the Desert Southwest and northern Mexico. Moisture pulled
northeastward in the southwest flow aloft still looks to remain well
to the west of our forecast area Tuesday. However...this moisture
may begin to advance eastward along and ahead of the next cold
front...possibly approaching our doorstep by Wednesday. We will keep
probability of precipitation low late in the extended given low confidence and much
uncertainty. Otherwise...temperatures should continue to moderate
during the early to middle part of next week. /21

&&

Aviation...
30.12z issuance...
VFR conditions through 31.12z. Winds will continue from the north at
7 to 10 knots today diminishing to 5 knots or less late tonight and
early Friday morning. 32/ee

&&

Marine...a moderate to occasionally strong northerly wind flow
will persist over the marine area through middle morning today then
gradually diminish through early this evening...then rebuild
slightly overnight and early Friday morning due to cold air drainage.
As a result small craft should exercise caution early today and
possibly again early Friday morning...mostly over the open Gulf waters
including the lower end of Mobile Bay and the Mississippi Sound. By
late Friday and Friday night a much stronger/deeper surge of colder air
will advect south over the northern and central Gulf leading to
small craft conditions for the entire marine area Friday night through
midday Sat. Gusts to near gale force will also be possible mostly
well offshore and over the lower end of Mobile Bay. Seas up to 9
feet mainly well offshore will be likely with the second cold front
late Friday night and early Sat. By late sun into Monday strong high
pressure to the north shifts east to the eastern Seaboard resulting
in a moderate to strong easterly wind flow over the marine area by
early next week. As a result seas will be slow to subside over the
weekend into early next week. 32/ee

&&

Fire weather...a cooler and much drier airmass will spread across
the central Gulf Coast region today. Relative humidity values will
drop to near or just below critical levels across much of the area
this afternoon...but durations should be brief and other criteria do
not look to meet red flag conditions. A reinforcing surge of colder
and drier air arrives this weekend...with another round of near
critical relative humidity values are expected this weekend...
especially Saturday afternoon when minimum relative humidity values drop into the
middle 20 percent range. We will continue to monitor other criteria over
the next couple of days to determine if fire weather headlines need
to be included across portions of the region. /21

&&

Preliminary point temps/pops...
Mobile 74 45 74 39 58 / 00 00 00 00 00
Pensacola 76 48 73 43 59 / 00 00 00 00 00
Destin 75 51 71 44 59 / 00 00 00 00 00
Evergreen 72 40 74 36 58 / 00 00 00 00 00
Waynesboro 73 40 72 34 58 / 00 00 00 00 00
Camden 71 40 72 34 58 / 00 00 00 00 00
Crestview 75 38 75 39 60 / 00 00 00 00 00

&&

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

$$

32/21

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