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Area forecast discussion...updated 
National Weather Service Mobile Alabama
1116 PM CST Friday Dec 26 2014

Marine...have updated to issue a Small Craft Advisory for the
Alabama waters out 60 nm. Winds at 42012 and 42040 have increased to
Small Craft Advisory criteria and will maintain sufficient duration
to warrant the advisory overnight. /29

&&

Aviation...
06z issuance...a VFR ceiling near 8 kft gradually lowers to an IFR
ceiling by 21z Saturday to 00z Sunday while east winds near 5-10 knots
become southeasterly 10-13 knots. Will have prevailing light rain by
15z Saturday with moderate showers by 18z and thunderstorms mixing in
by near 21z Saturday. /29

&&

Previous discussion... /issued 941 PM CST Friday Dec 26 2014/

Update...have delayed the onset of rain chances to until late
tonight and also made minor adjustments to cloud cover trends and
overnight lows. Update out soon. /29

Previous discussion... /issued 536 PM CST Friday Dec 26 2014/

Aviation...
00z issuance...VFR conditions begin the taf period then will have a
MVFR ceiling developing by 15z Saturday. Prevailing light rain also
begins at 15z with moderate showers prevailing by 18z. Expect to see
some thunderstorms mixed in during the late afternoon hours after
20z. Light easterly winds become southeast by 18z Saturday. /29

Previous discussion... /issued 330 PM CST Friday Dec 26 2014/

Short term [tonight through saturday]...warm conveyor belt
beginning to develop across the region in response to the
approaching low pressure system over the southwestern United States.
Atmosphere will continue to moisten and upper level southwesterly
wind flow strengthen as this system approaches. Layer precipitable
waters should increase to close to 2.0 inches (2 Standard deviations
above normal) by Saturday afternoon...up from .40 inches this
morning. Light rainfall is expected to begin falling over our
southeastern Mississippi counties late tonight...early Saturday
morning then southwestern Alabama during the morning and Florida by
early afternoon...minor short waves propagating through the nearly
saturated atmosphere overlying the area will trigger periodic
showers and isolated thunderstorms during the afternoon. Rainfall
totals of a half to two inches are possible with the heaviest
amounts west...over southeast Mississippi. Thickening cloud cover
tonight will keep overnight low temperatures in the 40 and 50s.
Despite cloud cover and rain...warm air advection over the region
will create daytime highs in the 60s. /08 jw

[saturday night through sunday]...an area of low pressure will
develop off the Texas coast Saturday night as a shortwave drops into
the Southern Plains. This low will then move northeast across
southern Mississippi Sunday morning and into the Carolinas by Sunday
night. This will generate widespread showers and thunderstorms
across the area Saturday night into Sunday as a cold front
approaches from the west. Severe thunderstorms are not expected due
to limited instability. A marginal risk for a strong storm may exist
on Sunday just ahead of the front. However...by that point the
higher shear values will have moved away from the area. At this
time...the primary threat will be locally heavy rainfall amounts
with a general 1 to 3 inches expected...isolated higher totals
especially across western areas. /13

Long term [monday through friday]...the cold front will move east
of the area Sunday night/Monday morning with a drier and cooler
airmass moving into the area through the middle of next week. Rain
chances return late in the week as another area of low pressure
develops over the northwestern Gulf and moves northeast in response
to an upper trough moving into the Southern Plains. High temperatures will
be in the upper 50s and lower 60s through the period. Lows will
generally be in the 40s and 50s. /13

Marine...high pressure over the area gradually shifts east as a cold
front approaches from the west. In response...moderate easterly flow
gradually becomes southeasterly by Saturday afternoon and turns
southerly Saturday night. A moderate northwesterly flow follows in
the wake of the cold front Sunday night. A northerly flow will then
persist through middle week. /08 jw

&&

Preliminary point temps/pops...
Mobile 51 65 62 72 53 / 20 80 70 60 50
Pensacola 50 65 62 73 57 / 10 50 50 40 50
Destin 52 65 63 72 60 / 10 40 40 40 50
Evergreen 41 64 57 72 53 / 10 70 70 70 60
Waynesboro 44 63 58 68 49 / 40 100 90 90 50
Camden 41 62 55 71 50 / 20 80 80 80 70
Crestview 40 64 58 74 56 / 10 40 50 40 60

&&

Mob watches/warnings/advisories...
Alabama...none.
Florida...none.
MS...none.
GM...Small Craft Advisory until 6 am Saturday for the following
zones: coastal waters from Pensacola Florida to Pascagoula MS
out 20 nm...waters from Pensacola Florida to Pascagoula MS from
20 to 60 nm...

&&

$$

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