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fxus64 kmob 200513 aab 
afdmob

Area forecast discussion...updated
National Weather Service Mobile Alabama
1113 PM CST sun Nov 19 2017

Discussion...updated for latest aviation discussion below.

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Aviation...
06z issuance...light northerly wind forecast overnight with
scattered high based cirrus streaming across the Gulf Coast. VFR
conditions. /10



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Previous discussion... /issued 515 PM CST sun Nov 19 2017/

Discussion...updated for latest aviation discussion below.

Aviation...
00z issuance...a general light northwest to northerly wind
forecast overnight. VFR conditions. /10

Previous discussion... /issued 338 PM CST sun Nov 19 2017/

Near term /now through Monday/...mid to upper short wave trof that
help usher the colder air over the forecast area this morning will
shift east over the western Atlantic this evening. To the north
another vigorous short wave or clipper will move south out of
central Canada and begin to dig south over the central conus by late
Mon afternoon. Near the sfc a broad ridge of high pressure will
continue to settle over the north central Gulf and se states through
tonight then shift east to Carolina/Georgia coast by late Mon
afternoon. With this pattern northern winds will begin to diminish
this evening and continue through tonight shifting northeast then
east by midday Mon. Model soundings show a better flow from the
south and southwest by Mon afternoon leading to increasing mid to
high clouds by late Mon afternoon.

As for temps the main concern continues to be a light freeze
occurring over most northern counties of the forecast area tonight,
or generally along and north of a line stretching from Janice in
Mississippi to Brantley in Alabama. Temps will dip just below
freezing in these areas mostly from 4 and 6 am CST Mon morning.
As a result a freeze warning continues for these areas tonight.
Further south low temps will range from the mid to upper 30s
inland and the lower to middle 40s along immediate coast. Highs
Mon will be similar to today ranging from the upper 50s to lower
60s over the northern half of the forecast area and the lower to
middle 60s further south to the immediate coast. 32/ee

Short term /Monday night through Wednesday night/...an upper trof
amplifies significantly over the eastern states and Gulf of Mexico
through Tuesday and persists through Wednesday night. A surface
ridge over the Gulf Coast states gradually weakens through Tuesday
while a surface low well to the north brings a trailing cold front
to near the lower Mississippi River valley. As this occurs, a
surface low is also expected to develop over the extreme northeast
Gulf, which leads to the development of a light northerly surface
flow over the forecast area ahead of the front. The front moves
through the forecast area Tuesday night and becomes associated
with the surface low over the extreme northeast Gulf, resulting in
a northerly flow continuing over the forecast area through
Wednesday night. Prior to the development of the surface low and
passage of the front, very dry deep layer air over the region
improves modestly through Tuesday, then decreases again later in
the period as the northerly flow becomes established. While dry
conditions prevail through the period, isolated to possibly
scattered showers are forecast for Tuesday mainly over the western
Florida Panhandle and part of south central Alabama due to some
wrap around precipitation with the surface low over the northeast
Gulf. Lows Monday night range from the mid 30s to near 40 inland
to the mid 40s closer to the coast then trend a bit warmer for Tuesday
night with lower to mid 40s for much of the area except for around
50 at the coast. Highs on Tuesday will be in the mid 60s well inland
with upper 60s closer to the coast, then as cooler air flows into
the area in the wake of the front, highs on Wednesday will be in
the lower 60s inland with mid/upper 60s closer to the coast. As
the cooler air continues to move into the region, lows Wednesday
night will range from mid 30s to near 40 along and west of I-65
with lower to mid 40s further to the east. /29

Long term /Thursday through Sunday/...the large upper trof
partially shifts into the western Atlantic on Friday but then is
reinforced over the eastern states by another system which moves
from the plains into the upper trof pattern. The surface low over
the extreme northeast Gulf ejects off into the western Atlantic
through Friday while a surface ridge settles into the southeastern
states. A surface low well to the north meanwhile brings another
cold front across the plains which is expected to move through the
forecast area Saturday night. While a brief southerly flow may
develop ahead of the approaching front, this is not sufficient to
return much moisture to the area, so expect a dry forecast to
continue through the area despite the frontal passage.

Highs on Thursday will range from the mid 50s to near 60 along and
west of I-65 with lower to mid 60s further to the east then trend
warmer through Saturday when highs will be in the upper 60s to
near 70 across the area. Overnight lows likewise trend warmer with
Thursday night having mid to upper 30s for much of the inland
areas and lower to mid 40s at the coast trending by Saturday night
to mid 40s inland and near 50 at the coast. In the wake of the
cold front, Sunday will be a bit cooler with lower 60s well inland
ranging to upper 60s at the coast then Sunday night will see
upper 30s well inland to lower/mid 40s closer to the coast. /29

Marine...northerly winds and seas will gradually subside tonight
through early Mon as a broad surface ridge of high pressure builds
from the lower Mississippi River valley to the southeast states
through early Mon afternoon, then further east to the
Carolina/Georgia coast by late Mon afternoon. A light easterly wind
develops by Mon afternoon and evening, shifting northeast overnight
and on Tue in response to a weak sfc trof/low forming over the
northeast Gulf generally south of Apalachicola FL. To the north
another surge of cold air will move south to the northern and
central Gulf by Wed leading to a moderate to strong offshore flow
late Wed through early Fri morning. Better rain chances are also
expected with this pattern with bulk of the precip remaining east of
Pensacola FL throughout the week. Seas will subside to 4 to 6 feet
later tonight then 2 to 3 feet on Tue. Small craft advisories will
continue over the open Gulf waters through 3 am Mon morning be
possible with this next surge of cold air mostly Wed night through
early Thu. 32/ee

&&

Mob watches/warnings/advisories...
Alabama...freeze warning until 8 am CST Monday for alz051>058.

Florida...none.
MS...freeze warning until 8 am CST Monday for msz067-075-076.

GM...Small Craft Advisory until 3 am CST Monday for gmz650-655-670-
675.

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