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Area forecast discussion...aviation update 
National Weather Service Mobile Alabama
1238 PM CDT Wednesday Jun 3 2015

031800z issuance...overall VFR conditions are expected across the flying area. Isolated
showers and thunderstorms are still possible near the coast this afternoon. Conditions
in and around these storms could temporarily fall to IFR. Any isolated shower activity will
dissipate or move offshore during the evening. /08


Previous discussion.../issued 456 am CDT Jun 3 2015/

Short term...(today through friday)...for today through tonight...
deeper dry layer airmass working into the region as middle/upper trough
axis has moved off to the east. A weakly reflected trailing surface trough
will linger over or near the forecast area today and tonight. Even with
this weak lolvl focus...the drier middle/upper level airmass will result
in a continuation of the decreased rain chances across the area today
and tonight. The drier airmass has also resulted in little to no
patchy fog across the region early this morning. Precipitation will
be a very typical diurnal early Summer like pattern. Will have
scattered showers over the marine area and near the coast early this
morning...then scattered showers and storms building inland during
the afternoon and early evening hours. Marine convection is expected
once again late tonight. Afternoon heating will be the primary source
for inland convection...and with no shear or any real dynamical
support...any severe weather threat will be extremely low. High
temperatures today expected to be in the middle to upper 80s...low
temperatures tonight ranging from the middle 60s over most of the
interior zones to the lower 70s closer to the coast.

The microburst risk for today is low.


Thursday through Friday...latest 00z guidance continues to advertise
the upper low over eastern portions of the tenn River Valley
meandering over the NC coastline by Friday evening.
Working with other pieces of shortwave energy moving over the upper
ridge over the upper trough is dug over the eastern
Seaboard. The low level flow over the southeastern states continues
to be disorganized...but with the disorganization comes no resistanceto
a Gulf Breeze moving inland during the afternoon hours. Best probability of precipitation are
being advertised over the Florida Panhandle...closer to the upper system
and eastern upper trough...with around to a bit below seasonal for
the numbers. For or a bit above continue to be advertised.

Long term...(friday night on)...Friday night through Sunday
night...the upper trough over the southeastern Continental U.S. Remains pretty
much as is...providing a Pivot Point as a strong shortwave diving
southeast over the northeastern Continental U.S. Draws an upper system over the
California coast inland over the Desert Southwest. The upper ridge
over the plains flattens and shifts eastward over the Southern
Plains...with another upper ridge over the open Atlantic building
eastward over the Caribbean. With a weakening of the southern end of
the eastern trough and the upper ridge building west over the
Caribbean...a surface ridge builds west over the northern Gulf Coast
and onshore flow becomes re-established over the forecast area by Monday morning.
Temperatures remain a bit above seasonal. Probability of precipitation...with the upper ridge
shifting east a bit over the plains...and the upper ridge
weakening...the chance drops...with a slight chance of
afternoon/evening thunderstorms and rain over the weekend.

Monday through Wednesday...a second strong vorticity lobe swings around an
upper low meandering around north of the Great Lakes...first shoving
the plains upper ridge south...then allowing it to build north over
the western Continental U.S. As the lobe moves east of the miss river. The upper
ridge that has built west over the Caribbean gets a southward shove
Tuesday night through Wednesday...taking the surface ridge over the
northern Gulf Coast with. By Wednesday evening...the surface ridge
has moved south...stretching west over the eastern Gulf of mex. A
weak front moves south across the lower miss River Valley and
southeastern Continental U.S. During this period...though timing varies
according to the model. The European model (ecmwf) moves the front over the
southeastern sates Monday night into Tuesday before
stalling...whilst the GFS has the front pushing close to the coast
Wednesday...before stalling late Wednesday. Both advertise an
increase in the chance of rain into middle week along with a bit of a
cooling around seasonal levels. With the GFS and European model (ecmwf) in
pretty good agreement and the GFS ensembles backing them up...see no
reason to diverge.


03/12z issuance...generally VFR conditions prevailing across the
region early this morning...but isolated rain showers/thunderstorms and rain along the coast
and over the adjacent Gulf waters resulting in localized areas of IFR
ceilings and visibilities. Much the same expected to continue through today and
into this evening. Will basically just call for showers or
thunderstorms in the vicinity of taf sites over next 24 hours.
General light and variable wind flow...but shifting from north
component early this morning to southerly component during the day
(mainly near the coast) and back to southerly component tonight.


Marine...a weak ridge of surface high pressure will remain draped
across the Gulf into the weekend with a weak trough persisting just
inland from the coastal waters. Mainly a generally light and
variable wind flow is expected...but becoming light offshore late
nights and early mornings and light to moderate onshore during the
afternoon and into early evening hours with afternoon sea breeze
enhancement. Seas remain low through the period...locally higher
near isolated showers and storms. 12/ds


Preliminary point temps/pops...
Mobile 87 69 90 70 90 / 20 20 30 20 20
Pensacola 86 72 89 72 89 / 20 20 30 20 30
Destin 84 74 87 73 87 / 20 20 30 20 30
Evergreen 88 67 91 66 92 / 20 20 10 20 20
Waynesboro 87 65 91 66 93 / 10 10 05 10 05
Camden 86 66 91 66 91 / 10 10 05 10 10
Crestview 88 68 93 66 94 / 20 20 30 20 30


Mob watches/warnings/advisories...



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