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Area forecast discussion...updated 
National Weather Service Mobile Alabama
1139 am CST Monday Feb 8 2016

Discussion...updated for latest aviation discussion below.

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Aviation...
18z issuance...cold front surges east across the area this
afternoon...bringing strong west to northwest flow. Main hazards
this afternoon for approaches/departures will be strong wind
gusts...upwards of 28 to 33 knots. Scattered middle level cumulus/stratus
moves southeast across the central Gulf Coast this afternoon. /10

&&

Previous discussion... /issued 1106 am CST Monday Feb 8 2016/

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

Update...large...deep upper level trough continues to dig into the
southern US. The middle level height field is an anomaly with a large
area of 2 to 3 Standard deviations (std's) below the mean
overspreading the middle Mississippi River Valley. Heights continue to
lower with anomalies lowering to 3 to 4 std's below the mean and
expanding from central MS...eastward to Georgia by this evening.

The attendant cold front...moving across The Heart of the forecast
area surges east of the area through the afternoon. Although wind
speeds have yet to ramp up...they will soon. Upstream...in the wake
of the frontal passage...northwest flow has been strengthening with
gusts increasing to between 25 and 30 knots across central/northern
Mississippi...Louisiana...and Arkansas. Latest radar velocity wind
profiles show west northwest flow now between 40 and 50 knots between
3 and 6 kft off the surface. A percentage of this is expected to mix
down during the afternoon...bringing windy conditions and
temperatures holding nearly steady then fall during the middle and late
afternoon as cold advection processes will be underway. Wind Advisory
continues. /10

Previous discussion... /issued 531 am CST Monday Feb 8 2016/

Discussion...updated for latest aviation discussion below.

Aviation...
12z issuance...a strong front will cross the area this morning...
bringing stronger low level winds to the area as an upper low swirls
around over the upper miss River Valley and Ohio River valley. This
system will push wrap-around stratus to mainly the northern half of
the forecast area tonight. Am not expecting ceilings to fall close to fall
below IFR levels...though.

/16

Previous discussion... /issued 452 am CST Monday Feb 8 2016/

Near term /now through Monday night/...the first 24hrs of the
forecast is shaping up to be one of nuances. On the synoptic
scale...shortwave energy swirls around an upper low moving from
over Wisconsin to over the upper Ohio River valley. This pushes a
front across the forecast area today. The surface low associated with
the upper low moves east with the upper dynamics...and as a piece of
energy swirls around the eastern edge of the upper low...a second
surface low forms off the Delaware-Maryland-Virginia. The piece of energy causing the
surface low off the eastern Seaboard early this morning pushes a
strong front across the forecast area today as it sweeps around the
southwest side of the upper low. With the push from the upper
dynamics being today...winds with and immediately behind the front
will be strong...reaching near Wind Advisory levels (especially in
gusts). With frequent gusts above advisory levels...have left the
current Wind Advisory for the forecast area this afternoon and coastal
zones tonight as is. Temperatures today across the forecast area will range from
middle 50s northwest as cooler air gets pushed over the region...to
around 60 southeast with this area being the last to see the cooler
air move in. Tonight...the piece of energy sweeps around the base of
the upper low...pushing wrap-around stratus southeast over the forecast
area. Not expecting a strong enough push tonight for any light rain showers
though...so left precipitation out of the forecast. Lows tonight range from
the upper 20s northwest to middle 30s along the immediate coast...with
mixing from the winds tonight helping to offset any radiational
cooling. 16/Sam

Short term /Tuesday through Wednesday night/...a deep northwesterly
flow will maintain the cool and dry weather pattern over the region
Tuesday through Wednesday as surface high pressure shifts east across the
region. The surface ridge axis will shift just to the east of the forecast
area Wednesday night with a low level return flow developing. While
the northwesterly flow continues...winds will decrease and become
less gusty during the short term period. Clears skies and below
normal temperatures will continue. High temperatures both Tuesday and
Wednesday ranging from the middle/upper 40s inland to the lower 50s at
the coast. Low temperatures both Tuesday night and Wednesday nights
ranging from the middle/upper 20s inland to the low/middle 30s at the
coast. 12/ds

Long term /Thursday through Sunday/...the surface high pressure
mentioned in short term continues to move off to the east early in
the long term period as an area of low pressure develops well to the
northwest of the forecast area. GFS/European model (ecmwf) differ somewhat with this
system...especially toward the end of the period. GFS moves the
associated front south across the region during the day on
Friday...while the European model (ecmwf) moves the front across the area Friday
evening and overnight. Both solutions advertise return flow and
increasing moisture over forecast area as early as midday Thursday. The
08/06z GFS is in slightly better agreement and closer in timing to
the European model (ecmwf) than was the 08/00z...so some questions to the forecast at this
time. This system is slightly stronger than the past several frontal
passages...and with the increased low level moisture noted
above...may see a small chance for rain with its passage. Daytime
high temperatures moderate into the upper 50s and lower 60s Thursday
and into the low to middle 60s Friday. A little cooler for daytime highs
over the weekend in the wake of the front...with highs back into the
50s. Overnight low temperatures in the 40s Thursday and Friday
nights...cooling into the 30s Saturday night. 12/ds

Marine...a strong front will move south over the marine area today.
With a tight pressure gradient setting up along the northern Gulf
Coast from high pressure over the plains and surface lows over the
northeastern states...gale level winds look to be likely. The
pressure gradient remains tight into Wednesday before easing...so we
are expecting small craft level or higher winds to last into Wednesday.
Another weaker front will cross the marine area by late Friday bringing
a temporary rise in the winds to exercise caution levels...easing Friday
night. 16/Sam

&&

Mob watches/warnings/advisories...
Alabama...Wind Advisory until 6 PM CST this evening for alz051>060-261>264.

Wind Advisory until 6 am CST Tuesday for alz265-266.

Florida...Wind Advisory until 6 PM CST this evening for flz201-203-205.

Wind Advisory until 6 am CST Tuesday for flz202-204-206.

MS...Wind Advisory until 6 PM CST this evening for msz067-075-076-078-
079.

GM...Small Craft Advisory until noon CST today for gmz630>635-650-655-
670-675.

Small Craft Advisory from 1 PM Tuesday to 6 am CST Wednesday for
gmz630>635-650-655-670-675.

Gale Warning until 1 PM CST Tuesday for gmz630>635-650-655-670-
675.

&&

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