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Area forecast discussion 
National Weather Service Mobile Alabama
401 PM CDT Friday Jul 31 2015

Short term [tonight through saturday]...showers and thunderstorms
continue to develop along and south of a stalled frontal boundary
stretching from about Andalusia to just north of Mobile in Alabama...
moving southwest to west at 15-20 miles per hour. North of the front drier air
has worked south over much of the northern part of the forecast area
with surface dew points mixing out to the upper 50s to middle 60s in
some locations well to the north. For the remainder of today and
overnight the weak frontal boundary will drift slightly southward
later this evening and overnight then begin to drift northward during
the daylight hours on Sat. Latest model soundings across the region
continue to show deep moisture along and south of the front with
precipitable waters ranging from 2 to 2.2 inches combined with moderate instability
or mixed layered convective available potential energy ranging between 2500-3000 j/kg suggesting a
few strong thunderstorms will be possible later this afternoon or
early this evening. Aloft both the 12z GFS and 00z European model (ecmwf) physical
guidance depict another fairly vigorous middle to upper vorticity approaching
from the north later today mostly likely leading to better lift
supporting a few stronger pulse type storms later in the day mostly
before sunset or maximum heating. Later tonight mainly south of the front
expect scattered showers and thunderstorms to continue with periods
of heavy rain and lightning being the main threats. For Sat the
frontal boundary drifts slowly north with better coverage of showers
and thunderstorms developing along and south of the front later in
the day due to better heating and instability...along with better
moisture convergence in the lower levels advecting from the south due
to an increasing onshore flow later in the day. North of the front
conditions will remain less humid as dew points remain in the middle to
upper 60s. As for temperatures will lean towards the current mav guidance
and adjust slightly for consistency. Lows tonight will range from the
middle to upper 60s to the northwest...and to the lower 70s to NE for inland
areas...and the middle 70s to the south stretching to the immediate
coast. 32/ee

This afternoon's wet microburst risk is high.

[Rest of the weekend]...ridging aloft will persist across the
western Continental U.S. Through this weekend...keeping US on the eastern fringe
of its influence. At this time...models are not showing much in the
way of impulses rounding the eastern edge of the ridge...resulting
in low rain chances across the western half of the area. Scattered
convection will remain situated southeast of the I-65 corridor...
especially along the beaches and coastal waters...as that portion of
our area will still be dealing with the moisture from a stalled
boundary south of the area.

Drier air will continue to spread across the northern half of the
area...north of the I-10 corridor...this weekend in the wake of the
aforementioned boundary. Modeled precipitable water values are
coming in at 1.5 inches or less across that area on Sunday. This
drier air will bring relief from the humidity as heat indices will
only top out in the 99-103 range on Sunday. Still expecting
temperatures to soar into the middle and upper 90s across the area on
Sunday. It will still be hot across the area...but at least the
humidity and heat indices will be more bearable. 07/mb

Long term [monday through thursday]...not much change in the
pattern for the early part of the work week as the expansive middle and
upper level ridge remains parked across the western Continental U.S.. by middle
week...moisture starts to stream back into the area as we start
feeling the influence from surface high pressure that begins to build
into the Gulf. Rain chances bump up into the 30-40 percent range
area-wide...although scattered convection will remain focused
predominantly across the southern half of the area along the sea
breeze.

Daytime highs will begin a slow downward trend by middle week...topping
out in the low 90s. However...heat indices will remain above 100 yet
below criteria all week...especially with the return of higher dewpoints
later in the week. Overnight temperatures will continue to sound like
a broken record with middle to low 70s inland and upper 70s along the
coast. 07/mb

&&

Aviation...
31.18z issuance...mostly VFR conditions through 01.18z. Expect MVFR
to IFR ceilings mainly in and around showers and thunderstorms generally
from Andalusia to Mobile in Alabama...stretching south to the immediate
coast later this afternoon and this evening. Some storms could be
strong or severe by late afternoon or early evening possibly affecting
all taf sites in SW Alabama and the western Florida Panhandle. Gusty straight
line winds...very heavy rain and frequent lightning will accompany
the stronger thunderstorms. 32/ee

&&

Marine...a weak frontal boundary will linger over coastal areas of
Alabama and northwest Florida through the weekend. Showers and
thunderstorms can be expected along the front through early next
week. Generally a light to moderate onshore flow develops each day
with a light northerly flow redeveloping each night through early
next week...as high pressure continues to build to the north. 32/ee

&&

Preliminary point temps/pops...
Mobile 71 92 72 94 75 / 20 20 20 30 20
Pensacola 76 91 75 92 77 / 30 50 20 50 30
Destin 79 90 77 91 79 / 40 60 30 50 30
Evergreen 72 95 71 94 73 / 10 30 20 20 10
Waynesboro 67 95 67 96 72 / 10 05 05 10 10
Camden 71 96 71 95 74 / 10 10 05 10 05
Crestview 74 92 73 94 74 / 30 60 20 50 20

&&

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

&&

$$

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