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Area forecast discussion 
National Weather Service Mobile Alabama
1034 am CDT Friday Aug 29 2014

Aviation update for 29.1500 taf amend...tweaked the temperature groups
after re-computing the arrival time by linear extrapolation for the
convection offshore. Delayed about an hour or so for mob. Other tafs
not affected. Also included thunderstorms in the vicinity once the first round clears the
terminals. Further inland...expecting the leading edge of the band to
be along a line from near Atmore Alabama to Waynesboro Mississippi by
29... Thomasville to Butler Alabama by 30.0100z. This is not
too different from the NAM and GFS calculations which have the
showers and thunderstorms marching in after 18z.

&&

Mesoscale update...based on RUC...this afternoon's wet microburst
risk remains moderate. The arrival time of offshore convection by
linear extrapolation is for the leading edge of the band to be along
the beach shortly before noon....along a line from Mobile Alabama to
Crestview Florida around 2 PM...along a line from near Atmore Alabama to
Waynesboro Mississippi by 4 PM...and Thomasville to Butler Alabama by
about 8 PM.

&&

Previous discussion... /issued 438 am CDT Friday Aug 29 2014/

Short term (today and tonight)...an upper ridge will move eastward
today as an upper trough moves across the midwestern states.
Meanwhile...an upper low was located over the western Gulf. This will
setup a deep south to southwest flow pattern which will allow deep
tropical moisture to surge into the area as a tropical wave is drawn
north. Precipitable water values will climb to nearly 2.25 inches
across coastal areas during the afternoon. Scattered showers and
thunderstorms will increase in coverage across the marine area this
morning and move inland through the late morning and afternoon as the
tropical wave and associated moisture move north. As heating
increases over land scattered to numerous showers and thunderstorms
will develop...especially in the afternoon. The greatest coverage
will be across the southern third of the forecast area where the
highest deep layer moisture will be located. Far northern zones will
only see isolated coverage due to a drier airmass. Severe
thunderstorms are not expected but a few stronger storms could
produce gusty winds due to water loading in a very moist environment.
The primary threat will be locally heavy rainfall.

Rain chances will decrease briefly this evening before increasing
again after midnight as an upper disturbance approaching the area
from the west.

Highs will generally be in the low 90s with a few middle 90s possible
well inland where rain chances are lower. Cooler temperatures are expected
across southern area due to cloud cover and rain. Lows tonight will
generally be in the low to middle 70s with upper 70s near the coast. /13

This afternoon's wet microburst risk is: moderate.

(Saturday and sunday)...dissipating surface trough remains over the forecast
area while several weak upper level disturbances pass over the region
in the southwesterly flow aloft. Precipitable water values slightly
lower than Friday...but remain high around 2 inches. The moist
airmass...combined with the just mentioned weak dynamics will
continue to result in a chance for showers and storms over the
weekend. Will expect a primarily diurnal convective pattern...with
daytime heating providing the additional support for scattered
showers and storms...especially in the afternoon and evening hours.
Lingering isolated showers and storms expected overnight. Went with maximum
temperatures slightly below guidance both Saturday and Sunday due to
widespread cloudiness and good rain coverages...but most locations
still rising into the lower 90s. Saturday night low temperatures ranging
from the lower 70s over northern two thirds of forecast area...middle to
upper 70s down toward the coast. 12/ds

Long term (labor day through thursday)...unstable weather pattern
persists with abundant moisture and daytime heating producing daily
chances of showers and storms through the period. Overall chances
slightly lower than over the Labor Day weekend however...as upper ridging
builds over the area and suppresses lift somewhat. Generally expect
scattered showers and storms each afternoon and early
evening...becoming isolated overnight. Daytime highs in the low to
middle 90s through the period...overnight lows in the lower to upper 70s
north through south across the area. 12/ds

Aviation (29/12z issuance)...showers and thunderstorms will
increase in coverage near the terminals later this morning and
continue through the afternoon. Periods of MVFR/IFR conditions will
be possible in and around scattered to numerous showers and
thunderstorms. /13

Marine...a weak ridge of high pressure will extend from the western
Atlantic Ocean to the north central Gulf of Mexico through early
next week...and a light to occasionally moderate southeasterly flow
is expected to prevail through Tuesday. Moisture will spread
northward across the area today...and will remain in place through
the weekend. This pattern will bring an increasing chance of showers
and thunderstorms across the marine area through the weekend. /13

Fire weather...no headlines or concerns with high humidity and daily
rainfall expected. 12/ds

&&

Preliminary point temps/pops...
Mobile 92 76 90 76 90 / 60 40 50 30 30
Pensacola 92 78 91 78 89 / 60 40 50 30 30
Destin 92 81 88 81 87 / 60 40 40 30 30
Evergreen 94 73 92 72 92 / 30 30 60 30 30
Waynesboro 94 73 90 73 91 / 30 30 60 40 40
Camden 94 73 91 72 92 / 20 30 60 30 30
Crestview 93 73 93 72 92 / 60 30 50 30 30

&&

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

$$

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