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Area forecast discussion...update to aviation 
National Weather Service Mobile Alabama
1145 PM CDT Monday Jul 28 2014

06z issuance...some lingering thunderstorms and rain along and south of i10 will
create localized MVFR level cigs/visbys...otherwise...general VFR
conditions expected over the area.



Mesoscale update [tonight and tuesday]...a surface cold front has
made steady southward progress over the deep south...with the axis
of the front having moved to the central sections of the forecast
area this evening. South of the boundary...clusters of storms have
tracked south southeast and are now mostly offshore...except for a
few over Mobile/Baldwin County early this evening. With the continued
southward movement of the front and the southward translation of
narrow east to west zone of deep moisture south of the frontal
zone...storms will shift off the coast entirely over the next 1 to 3
hours. There remains a very small chance that an isolated storm can
become briefly severe along the coastal sections this evening...but
the way the radar data is looking early this appears the
risk is diminishing.

Have made some adjustments to probabilities of precipitation given
latest radar trends...moving the higher chances off the coast. No
other changes at this time. /10

The front will push offshore after midnight with skies quickly
clearing as drier air advects into the area. The drier air will allow
lows to drop into the middle-upper 60s well inland with lower 70s along
the coast.

Humidity values will lower even more during the day on Tuesday with
dewpoints dropping into the upper 50s/lower 60s in the afternoon. So
while highs will climb to around 90...heat indices will not be a
factor. 34/jfb


Previous discussion... /issued 630 PM CDT Monday Jul 28 2014/

Long term...for Tuesday night into Wednesday much cooler drier air continues
to advect southward over the central Gulf Coast region resulting in
possible record low temperatures for both the Mobile and Pensacola
areas Wednesday morning...including many other locations in the forecast
area. The current record low for Mobile for Wednesday is 67 and 66 for
Thursday...and 67 for both Wednesday and Thursday for Pensacola. Current forecast
temperatures for these areas are very close to these values or a degree or 2
lower. Otherwise...a deep persistent middle to upper level trough of low
pressure over much of the Mississippi River valley and eastern Continental U.S.
Including much of the deep south will remain in place through early
next week resulting in cooler drier weather through early Friday
followed by increasing rain chances Friday through early next
week...generally in response to better low level moisture advection
from the south due to a weak onshore flow developing late in the week
combined with increased forcing or lift in the middle levels due to a
series of weak impulses in the middle levels rounding the base of the
upper trough Friday through Monday...possibly continuing through midweek next
week. Due to continued dry air aloft and the strength of some of the
impulses approaching from the west and northwest a few strong
thunderstorms will be possible beginning late Friday continuing through
early next week. Strong winds...small hail and frequent lightning
strikes will continue to be the main with the stronger thunderstorms
over the weekend. More clouds than sun especially during the late
morning and afternoon hours can also be expected by Friday continuing
into early next week. As for temperatures will use a blend of the GFS
ensemble guidance and European model (ecmwf) extended temperatures and tweak for consistency
with surrounding weather forecast offices. Highs will be mostly in the upper 80s to lower
90s for most areas through the forecast period with lows in the middle 60s
for most inland areas through Friday and the upper 60s to lower 70s
through early next week. 32/ee

Marine...moderate to strong west to southwest winds will continue
across the marine area through this evening ahead of an approaching
cold front. Small craft should exercise caution. Scattered to
numerous showers and storms will accompany the front and some of the
storms could become strong with gusty winds and frequent lightning.

Winds will veer to the northwest late tonight in the wake of the
front and become light to moderate. The front dissipates south of
the coastal waters by midweek. A weak pressure gradient will be
present through the rest of the week...resulting in light and
variable winds. Seas this evening will be in the 3-4 feet range with
seas diminishing by early Tuesday morning. Seas 1-2 feet through the
rest of the week. 34/jfb

Fire weather...a very unseasonal like cold front will move south
across the central Gulf region late tonight and early Tuesday
morning. In the wake of the front much drier conditions can be
expected...especially for this time of the year...with afternoon
relative humidity values lowering to the middle 20 percentile range for
most inland areas generally east of the I-65 corridor and north of
the I-10 corridor in northwest Florida...and the lower to middle 30
percentile range for all other areas including most areas near the
coast on Wednesday. At this time a Fire Weather Watch or warning is
not anticipated due to 20 foot winds remaining below 10 knots
through Thursday. Otherwise...dispersions will continue to be good
through most of the week with rain chances returning late Thursday
into Friday.

Fog potential and other fog is expected through
Thursday followed by patchy early morning fog for some inland
especially in low lying areas. 32/ee


Preliminary point temps/pops...
Mobile 71 91 66 91 67 / 30 05 05 05 10
Pensacola 74 92 71 90 70 / 30 05 05 05 05
Destin 76 92 74 88 73 / 30 05 05 05 05
Evergreen 67 90 60 89 63 / 10 00 05 05 10
Waynesboro 66 89 61 90 64 / 10 05 05 10 10
Camden 66 89 60 89 63 / 10 05 10 05 10
Crestview 68 92 62 92 64 / 20 05 05 05 05


Mob watches/warnings/advisories...
Alabama...high rip current risk until 7 am Tuesday for the following
zones: lower Baldwin...lower Mobile...

Florida...high rip current risk until 7 am Tuesday for the following
zones: coastal Escambia...coastal Okaloosa...coastal Santa



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