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fxus64 kmob 241507 aab 
afdmob

Area forecast discussion...updated
National Weather Service Mobile Alabama
907 am CST Fri Feb 24 2017

Discussion...see updated information for land areas below.

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Update...extended the dense fog advisory through 10am based on
the latest observations showing dense fog persisting in some
areas. All updates have been sent. /13

&&

Previous discussion... /issued 625 am CST Fri Feb 24 2017/

Discussion...updated for latest aviation discussion below.

Aviation...
24/12z issuance...vlifr cigs/vsbys with low stratus and fog across
much of the area at 12z this morning, likely to persist until
around 15z. Thereafter MVFR to VFR cigs remainder of late morning
and afternoon before a return to IFR cigs/vsby after 25/03z
tonight as fog redevelops and then scattered showers move in from
west after 25/06z. Surface winds southeast to south up to around
10 knots through tonight. 12/ds

Previous discussion... /issued 432 am CST Fri Feb 24 2017/

Near term /now through Friday night/...high pressure ridge axis shifts
east of the forecast area today and begins to weaken as a cold front
begins to move toward the southeastern states from the west. With
this, prevailing surface wind flow has become light southeast,
bringing increased moisture into the area. As a result, widespread
fog has developed over the region early this morning and will
persist through mid morning. Visibilities at many locations have
been reduced to 1/4 mile or less, and a dense fog advisory has
been issued for most of the forecast area (except for interior
eastern zones of south central alabama) through 9 am. Widespread
low clouds and associated fog this morning, burning off by late
morning, but will have some increasing mid/high level clouds in
advance of the approaching cold front today. Still enough sunshine
today to warm things up, and with the southerly flow expect
another day with near record highs with afternoon temperatures
rising to the upper 70s and lower 80s most locations (mid 70s
along immediate coast). Cloud cover increases and precip chances
increase tonight as the aforementioned cold front approaches the
forecast area from the west, moving into our Mississippi counties
by around midnight and then east across the remainder of the
forecast area after midnight exiting east of the area around
daybreak Saturday. Isolated to scattered showers expected with the
frontal passage tonight, especially after midnight, maybe some
isolated thunderstorms, but instabilities are minimal and dynamics
weak so no severe weather is anticipated. Rain chances probably
ending over most of forecast area, except far eastern zones by
daybreak Saturday. Low temperatures tonight a good 10 degrees
above normal for this time of the year for many locations, with
lows ranging from lower 50s over interior northwestern counties to
near 60s coastal and far southeastern counties. 12/ds

Short term /Saturday through Sunday night/...front makes passage
Saturday morning with a drier airmass filtering over the region.
Following this front, surface high pressure builds eastward over
the deep south bringing a quiet weather pattern for the weekend.
Highs on Saturday in the mid to upper 60s northwest of I-65 to the
lower half of the 70s southeast of Interstate. Highs on Sunday
generally in the mid to upper 60s. Overnight lows Saturday night
look to dip back into the mid 30s mainly north of I-10. A few of
the typically colder spots over the interior could see lows at
freezing. Overnight lows moderate fairly quickly Sunday night to
mid 40s interior to mid 50s coast. /10

Long term /Monday through Thursday/...a more unsettled weather
pattern looks to be setting up to close out the month of February.
As low level ridge of high pressure becomes positioned to the
east, deep Gulf moisture opens up quickly on Monday and remains
nearly steady state thru Tuesday with precipitable water values
ranging from 1.3 to 1.5 inches. At same time, the passage of a
series of mid level impulses, embedded in the higher level
southwest flow, brings enough support for the return of a chance
of showers and storms. Will maintain this chance through
Wednesday, before the next frontal passage Thursday morning tapers
rain chances back.

For the most part, daytime highs are favored to well above
climatology, ranging from the lower to mid 70s Monday, then mid
to upper 70s Tuesday and Wednesday. Highs in the lower to mid 60s
Thursday in the wake of the frontal passage. Mild nights, trend
cooler into the upper 40s interior northwest to mid 50s coast by
Thursday morning. /10

Marine...high pressure will weaken over the coastal waters
today and a cold front will move south and east across the marine
area late tonight. A light to moderate southeast to south flow today
shifts to the west and northwest and increases to 15 to 20 knots
(with higher gusts) along with building seas late tonight into
Saturday. Small craft should exercise caution late tonight and
Saturday. A Small Craft Advisory may be required, but for now
guidance indicates winds just below Small Craft Advisory criteria, so will continue
to monitor for the possibility. Moderate offshore flow continues
through Sunday, becoming more easterly by the end of the day, then
moderate southeast to south winds expected through late Tuesday as
another frontal system take shape west of the marine area. This
developing system is stronger than Friday night system, and
associated onshore winds in advance of this second system are likely
to be stronger. Scec conditions continue through late Tuesday, with
Small Craft Advisory conditions possible by end of forecast period. 12/ds

&&

Mob watches/warnings/advisories...
Alabama...dense fog advisory until 10 am CST this morning for alz051>053-
055-056-059-261>266.

Florida...dense fog advisory until 10 am CST this morning for flz201>206.

MS...dense fog advisory until 10 am CST this morning for msz067-075-
076-078-079.

GM...none.
&&

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