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Area forecast discussion 
National Weather Service Mobile Alabama
403 am CST Sat Feb 28 2015

Short term (today through Monday night)...for today and
tonight...broad middle to upper trough over much of the western Continental U.S.
Will continue to dig through 12z sun. Well to the east a broad surface
ridge of high pressure centered over the Ohio River valley and middle
Atlantic region continues to drift east and south through tonight.
Further south persistent temperatures/pressure gradient along the northern Gulf
Coast will continue to usher a moderate northeast to easterly wind
flow over the County warning forecast area through tonight...though later today as surface
temperatures warm winds near the surface relax somewhat leading to a rather
pleasant afternoon compared to the last couple of days. Increasing
clouds mostly from the east and south late in the day are mostly
associated with a weak impulse tracking eastward over the northeast
Gulf...generally south of the Florida Panhandle. Better low to middle clouds
continue to shift north and west through tonight affecting mostly
the eastern half of the County warning forecast area through 12z sun. With the better clouds
to the east have adjusted latest forecast temperatures accordingly with
slightly warmer conditions occurring over most of the western half
of the County warning forecast area...thus leading ME to lean a degree or two higher than
the current mav guidance mainly where more sun than clouds is
expected. Todays highs will range from the upper 50s to lower 60s
over the eastern half and the lower to middle 60s to the west. Near
the immediate coast afternoon highs will continue to be in the
middle to upper 50s do to the cool sea surface temperatures combined with a
better flow from the east later in the day. Tonights lows will be
warmer with lows ranging from the lower to middle 40s inland and the
middle to upper 40s closer to the coast. 32/ee

For Sunday through Monday night...broad upper ridging over the Gulf
builds into the plains while an upper trough moves across the
northeast states and into the Atlantic. A strong surface ridge over
the southeast states weakens on Sunday then a surface low well to
the north associated with the upper trough brings a trailing cold
front deep into the southeast states Sunday night. The weak frontal
boundary lingers over the forecast area on Monday then dissipates or
returns as a weak warm front Monday night as a southerly flow is
established. The weakening of the surface ridge over the southeast
states leads to weak or negligible isentropic lift over the forecast
area on Sunday but have opted to keep in slight chance probability of precipitation for
Sunday with this issuance to blend with neighbors. Chance probability of precipitation
follow for interior areas Sunday night with the approach of the
frontal boundary...with slight chance probability of precipitation for the remaining
portion. Have gone with chance probability of precipitation for much of the area on Monday
with the weak boundary in place over the area...then mainly slight
chance probability of precipitation follow for Monday night. Thunderstorm development is
not expected through the period. Highs on Sunday will be in the middle
60s then mostly in the lower 70s on Monday. Lows Sunday night and
Monday night will be mild with lows in the lower to middle 50s. /29

Long term (tuesday through friday)...upper ridging shifts eastward
across the eastern states on Tuesday while a longwave trough evolves
over the western states. A surface low associated with the western
states trough advances quickly across the plains on Tuesday and across
the Great Lakes region Tuesday night meanwhile bringing a trailing
cold front into the southeast states. The front moves through the
forecast area Wednesday into Wednesday night followed by a surface
high building into the region through Friday as the longwave trough
advances into the eastern states. Slight chance to chance probability of precipitation
continue over the area through Tuesday night ahead of the
approaching front...with good chance to likely probability of precipitation for the frontal
passage. Chance probability of precipitation continue on Thursday for overrunning in the
wake of the front then probability of precipitation taper off Thursday night with dry
conditions for Friday. The best shear which occurs Wednesday night
and instability which occurs on Wednesday are out of phase with the
frontal passage. However...0-3 km MUCAPES of 500-1000 j/kg on
Wednesday afternoon combined with 0-1 km helicities potentially near
150 m2/s2 warrant introducing the mention of some strong
storms...and have opted to word this during Wednesday into Wednesday
night for now in the hazardous weather outlook. Highs Tuesday and
Wednesday will be in the lower to middle 70s then much cooler
temperatures follow in the wake of the front with highs on Thursday
in the upper 40s to lower 50s with some improvement on Friday. Lows
Tuesday night will be quite mild and in the lower 60s...then much
cooler temperatures follow in the wake of the cold front with lows
Thursday night in the upper 20s inland to lower 30s closer to the
coast. /29


12z issuance...VFR conditions through 28.20z followed by MVFR to VFR
ceilings through 29.00z then mostly MVFR to IFR ceilings and visibilities
through 29.12z. Expect a mix of middle to high clouds through the
tonight. Better low clouds will also be possible over the adjacent
Gulf waters spreading inland mostly over the western Florida Panhandle
and near the Alabama coast late today and overnight...affecting all
terminal sites. Winds will be northeast to east at 8 to 12 knots
through the forecast period. 32/ee


Marine...a moderate to strong northeast to easterly wind flow will
continue over the marine area through early Sunday...with winds
relaxing somewhat over the inland bays and the near shore waters
during the afternoon hours due mainly to afternoon heating. Well
offshore small craft conditions will continue through most of
tonight gradually diminishing early Sun morning through early next
week. Winds also veer to the southeast slowly through early next
week as surface ridge mostly to the north shifts east. A light onshore
flow continues through midweek followed by a better onshore flow
later in the week in response to developing cold front approaching
from the west and northwest. 32/ee


Preliminary point temps/pops...
Mobile 63 45 67 53 70 / 05 05 20 20 30
Pensacola 59 47 65 54 70 / 05 20 20 20 20
Destin 56 49 62 55 69 / 10 20 20 20 20
Evergreen 62 42 66 52 71 / 05 20 20 20 30
Waynesboro 62 42 66 51 66 / 05 05 20 50 50
Camden 61 42 64 52 68 / 05 20 20 40 40
Crestview 59 44 66 50 73 / 05 20 20 20 20


Mob watches/warnings/advisories...
GM...Small Craft Advisory until 10 am Saturday for the following
zones: coastal waters from Destin to Pensacola Florida out 20
nm...coastal waters from Pensacola Florida to Pascagoula MS out
20 nm...Mississippi Sound...southern Mobile Bay...

Small Craft Advisory until 3 am Sunday for the following zones:
waters from Destin to Pensacola Florida from 20 to 60 nm...
waters from Pensacola Florida to Pascagoula MS from 20 to 60



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