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Area forecast discussion...aviation update 
National Weather Service Mobile Alabama
1228 PM CDT Friday Aug 22 2014

Aviation (18z issuance)...predominantly VFR conditions are expected
to prevail through the next 24 hours. However...spotty thunderstorm
activity is again expected to fire up by middle afternoon creating MVFR
conditions in and around the storms. Storms though should be short
lived...quickly dissipating after sunset this evening. 08/jw

**************************previous forecast**************************

Hot and humid conditions will bring high heat indices and associated
heat impacts to the region today and Saturday.

Short term [today through Saturday night]...dangerous heat index
values ranging from 107 to 110 degrees will be likely for most inland
areas today beginning late this morning continuing through late this
afternoon. As a result a heat advisory is now in effect for the
entire forecast area starting from just north of the immediate coast
stretching well inland affecting most locations in the County warning forecast area today.
With deep ridging continuing over much of the central Gulf region and
lower MS River Valley combined with ample moisture in the boundary
layer...precipitable waters still around 1.85 inches for many locations...and
limited capping aloft has made todays rain forecast a little more
challenging...leading ME to lean towards the wetter mav
guidance...expanding these areas to the north and west generally
inland from the coast during the afternoon and early evening hours. A
more well defined Theta-E axis stretching from the north central part
of the County warning forecast area to the Alabama/MS coast is also noted from the current
mesoanalysis across the southeast Continental U.S.. current physical guidance also
depicts better coverage of thunderstorms than earlier expected. With
weak forcing also noted in the guidance most of the todays
thunderstorms should be short lived though a few strong thunderstorms
will still be possible...with strong gusty winds and frequent cloud
to ground lightning. As for temperatures will use a blend of the current met
and mav guidance resulting in highs mostly in the middle to upper 90s
for inland areas and the lower 90s along the immediate coast. Tonight
lows will range from the lower to middle 70s inland and the middle to
upper 70s along the immediate coast. 32/ee

This afternoon's wet microburst risk will be moderate.

The upper level ridge of high pressure will continue to expand across
much of the Mississippi and Tennessee Valley...and into the central
Gulf Coast region again Saturday. A weak area of surface low
pressure will be located in the vicinity of southeast Georgia...with
the associated trough axis stretching westward into south central
Alabama. Low level thermal ridging will once again become enhanced
across much of the forecast area again Saturday afternoon...with 925
mb temperatures looking to range from 27-29 c across the region.
Afternoon high temperatures should trend slightly upward...with
readings ranging from the middle 90s along the coast to the upper 90s to
around 100 degrees over inland areas. These hot temperatures combined
with surface dewpoints from around 70 inland to the lower to middle 70s
near the coast will again result in high afternoon heat indices
between 105 and 111 degrees across the forecast area. While a few
spots may stay just shy of the 108 degree advisory criteria...most
locations will experience heat indices close to or within the
advisory have opted to include the County warning forecast area in a heat
advisory again Saturday afternoon. Isolated afternoon thunderstorms
may develop across the region...particularly near the seabreeze
where precipitable water values will be locally enhanced between 1.7
and 1.9 inches. Convection should diminish with loss of daytime
heating. Mostly clear skies are expected again Saturday night with
overnight lows mostly in the 70s...except around 80 near the
immediate coast. /21

Long term [sunday through thursday]...the large upper level ridge of
high pressure will continue to expand across the Mississippi and
Tennessee Valley region and through much of the deep south again
Sunday. An inverted surface trough will stretch across the Florida
Panhandle into southwest Alabama and southeast Mississippi. Hot and
humid conditions will persist with these features...with temperatures
again ranging from the middle 90s to near 100. Heat indices may again
range from 105-110 across much of the region...and later shifts will
need to monitor for potential extension of the heat advisory across
portions of the area Sunday. Isolated showers and thunderstorms are
again possible Sunday...potentially more scattered in coverage across
eastern portions of the County warning forecast area where precipitable water values increase
to 1.8 to 2 inches by Sunday afternoon. The upper level ridge will
slowly pivot westward by Monday...still extending across much of the
the Mississippi and Tennessee Valley regions. Medium range solutions
are still in agreement with bringing an area of deeper moisture
southwestward into our forecast area on the southeastern and southern
periphery of the ridge axis by Monday afternoon. With precipitable waters
potentially increasing to over 2.25 least scattered
showers and thunderstorms look to be a good bet across the region...
and will trend probability of precipitation in the 30-50 percent range across the County warning forecast area
Monday. Upper ridging may build back eastward through the deep south
Tuesday into Wednesday before breaking down late in the week as
westerly flow increases ahead of the next trough over the central
Continental U.S.. we have trended probability of precipitation downward Tuesday and Wednesday as the
deeper moisture looks to move to the west of the region and as upper
ridging builds back in. Temperature-wise...the increased chance of
rain should knock highs down closer to normal Monday. Readings then
look to average near to slightly above normal through the remainder
of the extended forecast period. /21


Aviation [22.12z issuance]...mostly VFR conditions through the
23.12z. Could see lower ceilings mostly in and around scattered showers
or thunderstorms forming later this morning and this afternoon
continuing through about 23.01z. Winds will be mostly northwest to
west 4 to 6 knots today and early tonight becoming light and
variable overnight and early Thursday morning. 32/ee


Marine...high pressure will persist over the north central Gulf
through early Saturday then gradually weaken late Saturday through
early next week as an upper level disturbance approaches mostly from
the northeast. As a result a predominant light to moderate westerly
flow will continue through the weekend followed by a moderate to
occasionally strong easterly flow developing by next week. Seas will
gradually build with the easterly flow by early next week. Better
coverage of thunderstorms can also be expected over most of the
marine area by early next week. 32/ee


Preliminary point temps/pops...
Mobile 94 75 96 75 97 / 30 20 20 10 20
Pensacola 94 79 95 78 96 / 20 10 20 10 20
Destin 91 81 95 80 95 / 20 10 20 10 20
Evergreen 97 73 99 72 99 / 30 20 20 10 20
Waynesboro 96 72 98 73 99 / 30 20 20 10 20
Camden 98 72 99 75 98 / 30 20 10 10 20
Crestview 98 75 99 74 99 / 30 20 20 10 20


Mob watches/warnings/advisories...
Alabama...heat advisory from 11 am Friday to 7 PM Friday for the
following zones:
Crenshaw...Escambia...lower Baldwin...lower Mobile...
Monroe...upper Baldwin...upper Mobile...Washington... Wilcox...

Heat advisory from 11 am Saturday to 7 PM Saturday for the
following zones: Butler...Choctaw...Clarke...Conecuh...
Covington...Crenshaw...Escambia...lower Baldwin...lower
Mobile...Monroe...upper Baldwin...upper Mobile...

Florida...heat advisory from 11 am Friday to 7 PM Friday for the
following zones: coastal Escambia...coastal Okaloosa...coastal
Santa Rosa...inland Escambia...inland Okaloosa...inland
Santa Rosa...

Heat advisory from 11 am Saturday to 7 PM Saturday for the
following zones: coastal Escambia...coastal Okaloosa...
coastal Santa Rosa...inland Escambia...inland Okaloosa...
inland Santa Rosa...

MS...heat advisory from 11 am Friday to 7 PM Friday for the
following zones: George...Greene...Perry...stone...Wayne...

Heat advisory from 11 am Saturday to 7 PM Saturday for the
following zones: George...Greene...Perry...stone...Wayne...




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