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Area forecast discussion 
National Weather Service Mobile Alabama
407 PM CST sun Dec 28 2014

Short term (tonight and monday)...slow moving cold front currently
generally aligned with the I-65 corridor...and should be just east
of the forecast area by early this evening. However...as the surface front
moves on slowly off to the east...low/mid level ceilings will not
dissipate overnight as a weak shortwave currently over eastern Texas
approaches and moves east across the region overnight. This feature
will be weakening...but will be supplying enough upslope lift over
the shallow cold front boundary to maintain the clouds and produce
widespread light rains overnight. Likely probability of precipitation across nearly all of
the forecast area by late evening and through the early predawn morning
hours...gradually ending from west to east after sunrise Monday and
throughout the remainder of the day. Patchy fog near the coast early
this evening...then some patchy fog developing inland during the
overnight hours. Best rain chances on Monday will linger
primarily along and east of I-65 and over the western Florida
Panhandle. Cooler airmass begin to filter into the region tonight in
the wake of the front. Overnight min temperatures are expected to range
from the middle 40s over far northeastern interior counties to middle to
upper 50s far southeast and coastal. Expect maximum temperatures on Monday to
be 5 to 10 degrees cooler than those of today...with highs ranging
from the upper 50s far northwestern counties to the middle 60s
southeastern counties. 12/ds

(monday night through Tuesday night)...flow aloft becoming more zonal
Monday night through Tuesday night with northeast surface flow from a
very large high pressure system over the northern rockies and Great
Basin ridging east over the Ohio Valley into New England. The high
will expand further southeast Tuesday night bringing a modest
increase to winds...and a modest decrease to temperatures...near the
surface over our region. The cold front expected to have already
passed our area will continue to push south over the Gulf of Mexico
through Tuesday night with that high to the northwest continuing to
spread over our region. Relatively dry air will move in with skies
clearing Tuesday. Lows Monday night in the 40s and Tuesday night in
the middle 30s. Highs Tuesday near normal ranging from near 60 to the
middle 60s. /77

Long term (wednesday through sunday)...that high migrating south
from the Great Basin and northern rockies will ridge southeast into
the western Atlantic and southern Gulf of Mexico Wednesday morning.
The central pressure will remain high at 1048 mb over western Kansas.
The high will migrate south-southeast through midweek over Oklahoma
Wednesday evening. It will then move eastward over the southeast
United States by late Thursday...keeping US rain-free until then. The
high will then move very quickly over the western Atlantic bringing a
return flow and increasing humidity and cloud cover across the region
the latter half of week. The upper features at the same time will
have perturbations embedded in the flow which will move east-
northeast across the region. That will bring scattered showers into
our area Thursday night and Friday. An upper low producing the
disturbances will then move east-northeast out of the Southern Plains
and dampen into an open wave before reaching the Ohio Valley region
by noon Saturday. It appears this will east a harbinger of a pattern
very similar to the system we had this weekend...for next weekend.
Models calculate that a 300mb jet maximum ahead of the open Ohio Valley
trough will increase to between 140 to 170 knots from Mississippi
across the Great Lakes region and over southwest Canada by noon
Saturday. Both the GFS and European model (ecmwf) models however develop a stronger
low level jet of 35 to 50 knots over the forecast area. As a
result...introduced likely rain showers with slight chance of
thunderstorms for Saturday. A cold front approaching the region from
the northwest Saturday morning should pass through the forecast area
late Saturday as output by the Euro. The GFS is slower with the
frontal passage...so we kept the chance probability of precipitation forecast southeast of
I-65 for Sunday.

Temperature forecast relatively unchanged. Minimum temperatures
Wednesday night in the lower to middle 30s most areas but above freezing
except extreme northeastern portions of our region. Lows rebound
later in the week to become more seasonable in the 40s Thursday night
and 50s over the weekend. Highs in the 50s Wednesday will also
rebound into the 50s to the 60s over the weekend. /77

&&

Marine...a light mainly south to southwest flow late this afternoon
and early this evening will switch to west through north overnight
in the wake of the passage of a cold front. Look for the light to
occasionally moderate offshore flow to continue through late week...while
becoming slightly more northeasterly. Little change in seas this
week. Waves primarily in the 2 to 3 foot range with a light chop on
protected waters. Periods of light rain over the marine area tonight
with areas of patchy fog also likely (especially near shore). Rains
ending from west to east on Monday. 12/ds

&&

Aviation...29.00z taf cycle...most of the region VFR with regard to
ceilings at beginning of the period...but some IFR areas of fog at
the surface...especially for locations near the coast. Becoming IFR all
areas overnight as low clouds...fog and light rains develop. LIFR
conditions possible in some locations. Conditions begin to improve
from west to east across the region during the day on Monday...with
MVFR conditions gradually returning. Light mainly west to southwest
winds this evening becoming more northwesterly overnight and light
north on Monday. 12/ds

&&

Preliminary point temps/pops...
Mobile 51 63 47 61 38 / 60 20 05 05 10
Pensacola 56 66 51 63 42 / 50 40 05 05 10
Destin 60 65 54 63 46 / 50 50 05 05 10
Evergreen 52 64 45 62 36 / 60 30 05 05 05
Waynesboro 47 60 43 59 34 / 80 20 05 05 10
Camden 49 61 43 61 34 / 80 20 05 05 05
Crestview 56 66 48 63 39 / 60 50 05 05 10

&&

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

$$

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