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Area forecast discussion...updated 
National Weather Service Mobile Alabama
1143 PM CDT Thursday Sep 18 2014

Aviation [19.06z issuance]...VFR conditions through 20.06z with the
exception of possible MVFR visibility conditions due to fog between
19.09z to 19.14z. Winds will be variable less then 3 knots overnight
and early Friday morning...becoming mostly east-southeast at 8 to 10
knots after 19.14z. Added thunderstorms in the vicinity for the Friday afternoon time frame.

Previous discussion... /issued 410 PM CDT Thursday Sep 18 2014/

Short term [tonight through saturday]...scattered showers and
thunderstorms have begun to form over coastal sections of Alabama and
nwfl stretching west into lower parts of southeast MS...moving west at 5 to
10 miles per hour. This afternoons convection continues to form along and south
of a weak frontal boundary that continues to stretch across the
forecast area this afternoon with the main concern being periods of
heavy rain...frequent cloud to ground lightning and gusty straight
line winds. With slightly better middle level forcing along with
slightly drier aloft wind gusts up to 40 knots will be possible with
some of the stronger storms through early this evening. The weak
front will remain mostly stationary over the region through this
evening then shift further south towards the coast by early Friday
morning. South of the front higher dewpoints and better rain chances
can be expected through Friday afternoon with the frontal boundary
shifting further inland over south central Alabama and the western Florida
Panhandle during the day on Friday. This pattern will result in better
rain chances over the eastern half of the forecast area on Friday
especially during the afternoon hours along a weak seabreeze front
that moves onshore by late afternoon. Will also mention patchy fog
for most inland areas after midnight tonight. As for temperatures will lean
towards current met guidance through Friday due to better high clouds
moving in from the west. Lows tonight will range from the middle to
upper 60s inland and the upper 60s to near 70 along the immediate
coast. Highs on Friday will climb to the lower 90s inland and the middle
to upper 80s along the immediate coast. 32/ee

This afternoon's wet microburst risk is moderate...generally over
western and lower sections of the forecast

Short range model solutions are in agreement that an upper level low
will pinch off in the vicinity of southeast Georgia and northern Florida Friday
night...while ridging aloft continues to build from south Texas to the
lower Mississippi Valley region. A dry northerly middle level flow
pattern will prevail across the central Gulf Coast region between
these features Friday night. Precipitable water values will continue
to fall to the 1.1 to 1.4 inches range across the County warning forecast area through Friday
night...with better deep layer moisture focused over the offshore
waters. We will therefore keep a dry forecast over most inland
locations Friday night...with a low chance of showers and storms
mentioned in the offshore marine zones. A surface ridge of high
pressure will otherwise extend from the appalachian mountain vicinity
southwestward to near the central Gulf Coast Friday night. Light
northeasterly winds are expected with lows ranging from the middle to
upper 60s inland to around 70 near the coast. The upper level low
will continue to drift in the vicinity of North Florida/southeast Georgia and
the adjacent coastal waters Saturday...while ridging aloft extends
across the lower Mississippi/Tennessee Valley region. A dry northerly
flow pattern aloft will persist Saturday. While isolated showers or
storms cannot be ruled out near the seabreeze...confidence remains
low enough to keep probability of precipitation below 20 percent across the region Saturday
afternoon. Highs should range from the middle 80s near the coast to the
upper 80s to around 90 inland. /21

Long term [sunday through thursday]...a dry northerly flow pattern
will persist Sunday before ridging aloft builds eastward toward the
central Gulf Coast region by early next week. A weak frontal boundary
will push southward into MS/al/GA early Monday as a shortwave trough
ejects southeastward across the Ohio/Tennessee Valley region on the base of a
middle level trough over the northeastern U.S. This boundary may push to
near the coast by Monday night into Tuesday morning. Will maintain a
dry forecast Sunday in the dry northerly flow pattern. A few showers
and storms may develop along and ahead of the approaching frontal
boundary Monday afternoon and evening...and will maintain a slight
chance of showers and thunderstorms in the forecast across most
locations. Thereafter...ridging aloft will continue to build from the
lower Mississippi Valley to the Great Lakes region Tuesday through
Thursday. Our forecast area will mostly remain under the influence of
this feature Tuesday through Thursday. Isolated to locally scattered
showers and thunderstorms should mostly remain focused near the
seabreeze through the extended period while temperatures remain close
to seasonal values. /21

Marine...a weak frontal boundary will linger near the marine area
through early Friday then shift well south as a strong ridge of high
pressure builds across the eastern Seaboard into the southeast
states. A moderate to occasionally strong easterly wind flow will
develop late Friday and continue through middle afternoon
Saturday...then build again late Saturday night through early Sunday
mostly due to high pressure reinforcing overnight. Winds diminish on
Sunday and continue into early next week as the ridge of high
pressure to the east weakens and shifts east. Easterly winds will
rebuild by midweek as another reinforcing shot of cooler air moves
south over the eastern Seaboard and southwest states. Small craft
will have to exercise caution for the stronger easterly flow late
Friday through early to middle afternoon on Sat. 32/ee


Preliminary point temps/pops...
Mobile 69 88 70 88 68 / 30 20 10 10 05
Pensacola 70 88 72 87 71 / 20 20 20 10 10
Destin 73 86 73 87 72 / 20 30 20 10 10
Evergreen 65 91 66 87 64 / 10 20 10 10 05
Waynesboro 66 91 66 90 65 / 20 05 10 10 05
Camden 64 92 65 88 65 / 10 10 10 05 05
Crestview 66 90 67 87 66 / 20 20 10 10 05


Mob watches/warnings/advisories...


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