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Area forecast discussion...updated 
National Weather Service Mobile Alabama
627 am CDT Tuesday Sep 23 2014

Update...low stratus continues to spread west over eastern sections
of the County warning forecast area this morning. Have decided to update the current zone
forecast to include low clouds and patchy fog for most of the eastern
half of the forecast area this morning. The low stratus and patchy
fog will slowly burn off late this morning and this afternoon. 32/ee

&&

Previous discussion... /issued 521 am CDT Tuesday Sep 23 2014/

Short term [today through Wednesday night]...a strong cold front
which moved over the northern Gulf waters earlier will continue to
allow drier cooler air to move south across the region through
tonight. With this pattern mostly sunny skies can be expected for
most areas later today with some low stratus moving westward across
eastern sections of the County warning forecast area through early this afternoon. This low
stratus should burn off by middle afternoon. A deep area of low pressure
located over the southeast Continental U.S. This morning...which helped generate
the low stratus to the east should begin to weaken and fill later
today and continue to weaken through the remainder of the week. Gusty
northerly winds especially along the coast will begin to gradually
diminish late this morning and this afternoon then rebuild slightly
overnight and early Wednesday morning...then diminish better during the day
on Wednesday. At this time a Wind Advisory is not anticipated through
tonight. As for temperatures low stratus to the east will help moderate temperatures
over much of the eastern half of the County warning forecast area through early to middle
afternoon. As for temperatures will use a blend of the current mav/met
guidance through tonight. 32/ee

An upper level low located in the vicinity of Georgia and western
portions of the Carolinas Wednesday morning will gradually open and
lift northward toward the Middle Atlantic States by Wednesday night...
while upper level ridging meanwhile continues to build from the
northwestern Gulf of Mexico to the vicinity of East Texas...
Louisiana...southern Arkansas and the adjacent lower Mississippi
Valley region. A deep layer dry airmass will remain in place across
our forecast area through Wednesday night...with precipitable water
values remaining under 1 inch across the region. No rain is therefore
expected. Surface ridging will maintain a light northeasterly flow
across our area through Wednesday night. High temperatures Wednesday
afternoon will average near normal...generally in the middle 80s across
most locations. Another cooler than average night is expected
Wednesday night...with lows ranging from around 60 to the lower 60s
across inland locations...to the middle 60s to around 70 near the coast.
/21

Long term [thursday through monday]...weak ridging aloft will remain
in place across the central Gulf Coast region Thursday. A fairly dry
and subsident airmass underneath this feature should maintain dry
conditions across the forecast area through Thursday night. The upper
level flow will gradually transition more southerly to southwesterly
across the central Gulf Coast region by late Friday and continuing
into the weekend between an upper level low moving little over the
plains states and upper ridging that will extend from the southeastern
U.S. To the Tennessee/Ohio Valley region. The increased south/southwest
flow aloft will draw moisture northward/northeastward from the northern
Gulf of Mexico into our forecast area late Friday and especially
this weekend. Precipitable water values look to increase to the 2 to
2.25 across much of the County warning forecast area Saturday and Sunday. The combination of
this increased moisture...embedded impulses in the southwest flow
aloft...and the presence of a surface boundary in the vicinity of
the coast will bring an increasing chance of showers and thunderstorms
to the forecast this weekend. We have kept probability of precipitation trended in the 40-50
percent range across most locations both days...but if trends
continue...even higher probability of precipitation may become necessary this weekend.
Locally heavy rainfall could be possible this weekend given the
amount of moisture available. Medium range solutions show differences
with the location and timing of the eventual northeastward movement
of the upper level trough early next week. Residual moisture in place
across the forecast area supports keeping at least a chance of
showers and thunderstorms in the forecast Monday. Otherwise...the
increasing low level moisture will allow for slightly above normal
low temperatures Friday through Monday...while high temperatures
should average near to slightly above normal during this period. /21

Aviation...
12z issuance
mostly VFR conditions through 24.12z. Could see MVFR to IFR
conditions early today due to low status moving in from the east.
This low status should burn by the afternoon hours. Gusty northeast
winds at 10 to 15 knots early today will diminish slightly this
afternoon then rebuild to 8 to 12 knots overnight and early Wednesday
morning. 32/ee

Marine...a moderate to strong northeasterly wind flow will persist
over the marine area through Wednesday afternoon as a strong surface
ridge of high pressure builds south across the north central Gulf
through Thursday. Small craft advisories are in effect for the
entire marine area this morning...continuing over the open Gulf
waters out to 60 nm including the lower end of Mobile Bay and the
Mississippi Sound through Wednesday afternoon. Seas up to 8 feet
will be possible well offshore late today through Wednesday. Winds
and seas will gradually diminish through Friday then rebuild again over
the weekend. 32/ee

&&

Preliminary point temps/pops...
Mobile 85 64 84 64 85 / 00 05 05 05 10
Pensacola 84 66 85 68 84 / 00 05 05 05 10
Destin 84 67 85 70 84 / 00 05 05 10 10
Evergreen 81 58 84 61 84 / 00 05 00 00 10
Waynesboro 84 58 85 61 86 / 00 05 00 00 05
Camden 83 57 85 60 85 / 00 05 00 00 05
Crestview 82 60 85 63 85 / 00 05 05 05 10

&&

Mob watches/warnings/advisories...
Alabama...none.
Florida...none.
MS...none.
GM...Small Craft Advisory until 7 PM Wednesday 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...waters
from Destin to Pensacola Florida from 20 to 60 nm...waters from
Pensacola Florida to Pascagoula MS from 20 to 60 nm...

Small Craft Advisory until 1 PM Tuesday for the following zones:
Choctawhatchee Bay...northern Mobile Bay...Pensacola Bay
system...Perdido Bay...

&&

$$

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