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Area forecast discussion 
National Weather Service Birmingham Alabama
345 am CDT sun Sep 21 2014

Discussion...

Under weak high pressure...skies are mostly clear and winds calm
across central Alabama. Temperatures have cooled into the low to
middle 60s this morning...about 5 degrees cooler than 24 hours ago.
Light fog has developed in isolated locations...most close to
bodies of water. Expect another sunny and dry day for most of the
area as temperatures warm into the middle 80s to lower 90s.

The surface ridge axis will slide southward this morning...allowing
low level winds to become westerly to southwesterly ahead of an
approaching quick-moving front associated with a trough amplifying
over the Ohio River valley. Not much if any moisture return ahead of
the front...and models are in good agreement that convection
should be confined to the front itself...which is currently
crossing the Ohio River with a broken line of showers and
thunderstorms. Models have this activity dropping into north
central Alabama late this afternoon. The strength of the
system...coupled with daytime heating...might result in a strong
wind gust or two...as is the case with most thunderstorms this time
of year but severe potential is low.

The front will quickly drop southward through the area
tonight...with convection diminishing in strength and coverage
with time. By sunrise...the front will be across southern portions
of the area. Enhancement of convection is possible with daytime
heating...but should be confined to far southeastern locations as
the front quickly moves south of the area. Strong surface high
pressure will move across the Midwest behind the front. Drier and
cooler air will filter southward...with highs on Monday in the
upper 70s north to upper 80s south...and overnight lows generally
in the 50s. Its possible a few of the typical cooler locations
across the far north could see upper 40s Tuesday morning.

With surface high pressure to our north through midweek...easterly
low level flow will continue to bring in cooler temperatures to at
least the east. Highs Tuesday and Wednesday will range from upper
70s to lower 80s. By Thursday...that easterly flow finally taps
into Atlantic moisture...as a weak upper level troughing develops between
ridging in the western Atlantic and Midwest. Expect clouds to
spread back into the area from the southeast and south. Models are
in fair agreement with holding off rainfall until at least
Friday...at which point solutions diverge regarding the strength
and timing of another upper level shortwave that rotates across
the area from the west. Will maintain low probability of precipitation for now for next
weekend.

14

&&

Aviation...
06z taf discussion.

VFR conditions are expected through the forecast period. Light and
variable winds will prevail overnight with fog development
unlikely with dry conditions in place. Isolated showers and storms
are expected late Sunday afternoon across north Alabama...but
certainly not enough confidence to include any mention in the tafs at
this time.

Note...the National Weather Service will begin issuing seasonal
terminal forecasts for the Talladega Municipal Airport (kasn) in
Talladega...Alabama. The forecast will begin October 5th at 00z
and last through at least the 23rd of October.

56/gdg



&&

Preliminary point temps/pops...
Gadsden 87 59 79 53 80 / 20 20 10 0 0
Anniston 87 61 80 55 80 / 10 20 10 0 0
Birmingham 89 60 81 56 81 / 20 20 10 0 0
Tuscaloosa 91 62 84 55 83 / 10 20 10 0 0
Calera 89 62 82 57 82 / 10 20 10 0 0
Auburn 88 65 84 60 82 / 10 20 20 10 0
Montgomery 90 65 86 59 84 / 10 20 20 10 0
Troy 89 65 87 59 84 / 10 10 20 10 10

&&

Bmx watches/warnings/advisories...
none.

&&

$$

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