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FXUS64 KMOB 241746 AAB

Area Forecast Discussion...UPDATED
National Weather Service Mobile AL
1146 AM CST Fri Nov 24 2017

.DISCUSSION...See updated information for land areas and aviation
discussion below.


.UPDATE...Only minor updates needed, mainly to adjust current
temps and bump today's high up a bit. Also have adjusted dewpoints
to better reflect current obs. Package out shortly.



18Z issuance...VFR conditions expected through the forecast.



.PREV DISCUSSION... /issued 516 AM CST Fri Nov 24 2017/ 

DISCUSSION...Updated for latest aviation discussion below.

12Z issuance...VFR conditions forecast in the near term. Light
winds. /10

PREV DISCUSSION... /issued 402 AM CST Fri Nov 24 2017/ 

NEAR TERM /Now Through Friday night/...Long wave high level trof
extends from the New England States to the central and eastern 
Gulf. East of the high level trof axis at the surface, a frontal 
boundary was positioned from off the southeast US coast to across 
the central Florida panhandle where a frontal wave of low pressure
will be lifting northeast. Although, environmental moisture is 
lacking, mid level impulses tracking eastward at the base of the 
long wave trof position may provide enough lift to squeeze out a 
small chance of rain over the coastal waters tonight. Otherwise, 
will maintain a rain-free forecast with axis of weak surface high 
over the local area. Today's highs mostly in the mid to upper 60s 
range which stands close to climate normals. Potential exists for 
the passage of higher based clouds tonight which would support 
leaning to the upper end of the guidance envelope on overnight 
lows. 39 to 44 along and northwest of I-65 to upper 40s/lower half
of the 50s along the coastal sections. /10 

SHORT TERM /Saturday Through Sunday night/...A dry weather
pattern will continue across our region through the weekend. The
next shortwave trough translating from the Ohio and Tennessee 
Valley regions toward the southeastern states will send an 
attendant cold front southward across our forecast area by 
Saturday evening. Dry northwest flow aloft will prevail Sunday 
into Sunday night, while surface high pressure meanwhile builds 
across the Tennessee Valley and adjacent southern states. Partly
sunny skies are expected Saturday with mid and upper clouds moving
overhead. Afternoon highs are forecast to range from the upper 60s
to the lower 70s. Skies gradually clear Saturday night as the
front passes across the region. Overnight lows should range from
around 40 to the mid 40s over the interior and in the upper 40s to
lower 50s near the immediate coast and beaches. Highs Sunday
should average in the mid 60s over northern portions of the CWA 
and in the upper 60s to around 70 over the remainder of the
region. Lows by Sunday night should average a little cooler with
readings in the mid to upper 30s over interior areas and in the
lower to mid 40s near the immediate coast and beaches. /21 

LONG TERM /Monday Through Thursday/...An upper level ridge of
high pressure extending from southern portions of Texas to the
Mid Mississippi Valley Monday is forecast to build eastward across
the central Gulf Coast region Tuesday into Tuesday night. A deep
layer dry and subsident airmass underneath this feature will
support mostly clear skies and dry conditions during the early
part of next week. Upper level flow should become more zonal 
Wednesday into Thursday as the ridge axis flattens/shifts south
and the next shortwave trough approaches the Tennessee/Ohio
Valleys. Surface flow transitions more southeasterly to southerly
Tuesday through Thursday as surface high pressure shifts across 
the eastern states. The return flow should allow for at least a
modest increase in low level moisture across the area. Medium 
range models also hint at weak lift and perhaps a few developing 
showers late Wednesday into Thursday, so will keep a slight chance
of rain in the forecast during this time frame. A modifying trend
in temperatures is otherwise expected Tuesday through Thursday. /21

MARINE...Weak high pressure over the coastal waters today and 
tonight, becomes reinforced by a stronger high expanding over the 
Mid-South late Saturday into Sunday. The result is a more 
established offshore flow. Seas generally 1 to 2 feet through the 
weekend with a gradual build in seas well offshore late Sunday. A 
more east to southeast flow sets up by Tuesday as high pressure 
moves to the east, becoming positioned from the west Atlantic to 
the southeast. /10



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