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Area forecast discussion 
National Weather Service Mobile Alabama
141 PM CDT Wednesday Oct 1 2014

Aviation...
update for 01/18z taf cycle...VFR conditions continue this afternoon
with scattered to broken ceilings...generally above 3000 feet. Some
areas of IFR conditions possible late tonight due to fog and low
clouds. Not likely enough for a tempo group. Generally light east to
southeast surface winds though tonight.

&&

Previous discussion... /issued 508 am CDT Wednesday Oct 1 2014/

Short term...(today through friday)...for today through tonight...
surface high pressure along the Atlantic Seaboard will continue to ridge
into the local forecast area from the northeast through tonight. In the
upper levels slight ridging is expected through tonight. This pattern
will result in little to no precipitation across the forecast area
through tonight. Along the western edge of the surface ridge enough
deeper layer moisture will return by tonight resulting in the
possibility of a few isolated showers (although most locations will
remain rain free through the short term period). Skies partly to
occasionally mostly cloudy through tonight...with some patchy fog also
possible in some areas overnight. Generally light east to southeast
wind today and tonight. Daytime maximum temperatures in the middle and upper 80s
over interior counties and in the low to middle 80s over the coastal
counties. Min temperatures tonight generally in the middle to upper 60s at
nearly all locations... except along the immediate coast where lows
in the lower 70s likely. 12/ds

Thursday through Friday...a strong shortwave swings east from over
the Desert Southwest to over the plains then middle miss River Valley as
a closed low moves over the northern plains to over the northern miss
River Valley. A surface low that has developed over western portions
of the Southern Plains heads towards the Great Lakes. This low
deepens once it comes under the influence of the energy moving across
the northern plains Thursday night into Friday. For the forecast area...this is
well north of the area...thus am not expecting to see any serious
increase in flow over the forecast area from off the Gulf (which will help to
limit wind shear ahead and with the frontal passage friday). Am still
expecting this passage to be in the Friday afternoon/evening time
frame. Enough instability (around 2000 l/kg during the day friday)
for some thunderstorms and rain to become strong to severe. Guidance is still limits
0-3km wind shear to generally less than 100 m^2/s^2. With the still
decent onshore flow...temperatures and probability of precipitation above seasonal expected.

Long term...(friday night on)...Friday night through Saturday...the
forecast area clears out as the surface high pressure moves east over the lower
miss River Valley. Guidance continues to advertise seasonably cool
temperatures for Friday night and Saturday. The European model (ecmwf) continues to be the
coolest...about 3-5 degrees than the GFS. Both solutions have cooled
down from yesterday's guidance by several degrees. Am continuing to
blend the European model (ecmwf) and GFS solutions as feel the answer lies in the
middle.

Saturday night through Sunday night...the cool-down continues as the
coolest portion of the airmass moves over the area(with surface high
pressure passing over then east of the fa). The cooling trend from
previous model runs continues...with even the GFS advertising temperatures
dipping into the 40s over most of the forecast area. With temperatures drops this run
being just one run...have trended the temperatures down a bit from
yesterday...but continue to go between the cooler European model (ecmwf) and warmer
GFS for the resultant temperatures. Also of note...by Monday morning...with the
centre of the surface high being east of the forecast area...a return to
onshore flow has begun...especially in the GFS.

Monday through Wednesday...guidance is diverging significantly...
with the European model (ecmwf) advertising a strong piece of energy moving east over
the southeastern Continental U.S. And pushing a re-enforcing front across the
southeastern Continental U.S. Monday night through Tuesday...whilst the GFS is
advertising the energy remaining...along with an associated
front...remaining north of the southeastern states. Either scenario
is possible...so have blended the cooler European model (ecmwf) with the warmer GFS
for the forecast...but feel that with limited moisture return ahead
of the front in the European model (ecmwf)...the chance of rain will be
negligible....so have kept probability of precipitation around seasonal levels.

Aviation...
01/12z issuance...VFR conditions today with scattered to only
occasionally broken ceilings...but above 3000 feet. It is possible
that there will be some areas of IFR conditions late tonight due to
fog and low clouds...but not widespread. Generally light east to
southeast surface winds both today and tonight. 12/ds

Marine...a ridge of surface high pressure north and east of the
marine area today will drift east off the US Atlantic coast through
early Friday as a cold front approaches the marine area from the
west. The cold front will move across the coastal waters late Friday
afternoon and evening...with strong high pressure building in its
wake. A light to occasionally moderate wind flow is expected to
continue over the coastal waters through early Friday...becoming a
moderate to strong offshore flow accompanied with building seas by
late Friday and into the weekend after the front pushes south of the
area. Showers and thunderstorms expected Thursday and Friday as the
front approaches and passes across the marine area. 12/ds

&&

Preliminary point temps/pops...
Mobile 86 73 86 76 84 / 05 20 40 40 60
Pensacola 86 71 84 76 84 / 05 10 30 30 60
Destin 83 72 82 77 82 / 00 10 20 30 60
Evergreen 88 67 89 74 82 / 00 10 30 30 60
Waynesboro 88 69 88 74 83 / 20 20 40 50 60
Camden 89 66 89 74 83 / 05 10 30 40 60
Crestview 87 65 87 74 84 / 00 10 20 30 60

&&

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

$$

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