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Area forecast discussion 
National Weather Service Mobile Alabama
issued by National Weather Service New Orleans la
327 PM CST Monday Mar 2 2015

Short term...multiple issues in the forecast. It has been foggy all
day and just as most of the fog has started to lift this afternoon it
should come crashing down once again this evening. Rain chances will
remain low until Wednesday afternoon and then increase for Wednesday
night and through Thursday mroning. Last but not least is the chance
of some winter weather for the far northwestern counties of the County Warning Area
overnight Wednesday.

Very rich moisture continues to move in from the Gulf and even
though fog has improved across the region things should change
rather quickly this evening especially over the western half of the
County Warning Area. Fog as previous forecaster mentioned will initially be the
thickest close to the coast and then spread north through the
evening. As for rain chances it looks like the region should remain
mostly rain free with ridge axis sliding across the region tonight
and into tomorrow morning.

Tuesday things should be quiet as SW flow begins to become
re-established over the region. A very positively tilted l/west trough
sets up from near the southern Hudson Bay stretching all the way to
the SW into the Baja California...yes the trough axis stretches from near the
Hudson Bay to the Baja California. While this occurs a strong short wave embedded in
the upstream will dig out of western/central Canada and into the
High Plains Tuesday night. This will be the feature that will drive
another cold airmass south and bring one more bout of winter weather
to the deep south. The cold front by Tuesday evening will be entering
the lower Mississippi Valley and and begin to slow down with the
bulk of the cold airmass just starting to work south across the
northern plains.

On Wednesday ahead of this front abundant moisture...unstable
conditions...and broad lift aloft will lead to scattered rain showers and thunderstorms and rain but
the bulk of the forcing will be with and Post frontal. This could
lead to an issue. The airmass will be rather cold and due to the
amount of snow and even ice to the north and northwest of the region
this airmass will not moderate much. Temperatures could quickly drop
to and below freezing in the far northwest overnight Wednesday with
precipitation continuing. In addition this airmass is quite shallow
with ll temperatures well above freezing and latest forecast sounding
indicate that whatever is falling should completely melt leading to
a possible freezing rain issue. There is still a great deal of
uncertainty with the GFS being the more aggressive model while the
European model (ecmwf) is has a smaller window for freezing rain that said it is
starting to look a little more likely that there will be some
freezing rain in the far northwest after 6/9z Thursday and possibly
continuing till 15/18z Thursday. Things should quickly taper off northwest to southeast
through the midday and afternoon hours. Will continue to indicate
this in the grids but if the GFS is right then the frozen precipitation
will need to be brought down further south some and a tad further
east. /Cab/

Long changes made to the extended portion of the forecast
and previous long term discussion has been appended. /Cab/

Dry conditions are expected Thursday night and Friday then slight
chance probability of precipitation return Friday night into Saturday and increase to chance
probability of precipitation by Sunday as a series of shortwaves move across the region.
Highs on Thursday will range from near 40 well inland to the lower
50s at the coast and lows Thursday night will range from the upper
20s inland to Lower/Middle 30s closer to the coast. Temperatures
gradually warm through the remainder of the period with lows
Saturday night in the lower to middle 40s and highs on Sunday in the
lower 60s. /29/


Aviation...MVFR conditions will be an issue through about 03z but
then all terminals should begin to get socked in again. IFR if not
LIFR ceilings and visibilities will quickly develop this evening and persist
through about 15z...possibly even lasting till 18z tomorrow. /Cab/

Marine...areas of dense fog will continue to all bays...sounds and
the near shore coastal waters tonight and possibly all the way into
Wednesday. A light southeast wind flow will continue over the marine
area through early Tuesday then shift south and build through
Wednesday evening ahead of a strong cold front approaching from the
northwest. The cold front is expected to move across the northern
Gulf by late Wednesday night into early Thursday morning...leading a
strong offshore flow over the marine area Thursday through early
Friday. Seas up to 9 feet well offshore will be possible in the wake
of the front. Northerly winds and seas will gradually diminish
through Saturday as a broad surface ridge builds to the north. A
Small Craft Advisory will be likely in the wake of the strong cold
front later in the week. 32/ee


Preliminary point temps/pops...
Mobile 58 73 60 77 37 / 20 20 20 50 50
Pensacola 59 72 62 75 47 / 20 20 20 40 50
Destin 59 70 62 73 53 / 20 10 20 30 40
Evergreen 59 76 59 80 41 / 20 20 20 40 70
Waynesboro 59 75 61 78 31 / 30 20 30 40 80
Camden 58 76 60 77 32 / 30 20 20 40 80
Crestview 58 76 58 79 51 / 20 10 20 30 50


Mob watches/warnings/advisories...
Alabama...dense fog advisory from 9 PM Monday to 9 am Tuesday for the
following zones: Butler...Choctaw...Clarke...Conecuh...
Covington...Crenshaw...Escambia...lower Baldwin...lower
Mobile...Monroe...upper Baldwin...upper Mobile...

Florida...dense fog advisory from 9 PM Monday to 9 am Tuesday for the
following zones: coastal Escambia...coastal Okaloosa...
coastal Santa Rosa...inland Escambia...inland Okaloosa...
inland Santa Rosa...

MS...dense fog advisory from 9 PM Monday to 9 am Tuesday for the
following zones: George...Greene...Perry...stone...Wayne...

GM...dense fog advisory until 9 am Tuesday for the following zones:
Choctawhatchee Bay...coastal waters from Destin to
Pensacola Florida out 20 nm...coastal waters from Pensacola Florida
to Pascagoula MS out 20 nm...Mississippi Sound...northern
Mobile Bay...Pensacola Bay system...Perdido Bay...southern
Mobile Bay...




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