Area Forecast Discussion
Issued by NWS Shreveport, LA

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FXUS64 KSHV 191147

Area Forecast Discussion
National Weather Service Shreveport LA
647 AM CDT Mon Mar 19 2018

For the 19/12z TAFs, a few showers, possibly an isolated
thunderstorm, will move across the area early in the period ahead
of an approaching cold front. Rain chances are too low to warrant
a mention in the TAFs, but if any showers do occur at any
terminals, the impacts should be short-lived. The rain should
move east of all TAF sites around 19/18z. Surface winds will
become westerly today. Speeds will increase early in the TAF
period to between 15 and 20 kts. Gusts up to 30 kts will be
possible. Winds will begin to veer to the northwest by 20/00z and
should decrease in speed slightly after sunset. However,
sustained speeds of 10 to 15 kts with gusts up to 20 kts will
generally prevail through the overnight hours. IFR/LIFR ceilings
across portions of East Texas and much of Louisiana and Southern
Arkansas will quickly lift into the VFR range by late morning as
the westerly winds bring drier air into the region.



.PREV DISCUSSION... /issued 508 AM CDT Mon Mar 19 2018/

Between the svr convection that fired across Lower E TX and the
Srn sections of Ncntrl LA Sunday evening, and the software and
hardware issues we are seeing with a few NWR transmitters this
morning, it has been a rather eventful last 12 hours, as now a
narrow line of convection has developed along the dryline that has
mixed E into Ecntrl TX/extreme SE OK into Wrn AR, ahead of the
compact closed low traversing Nrn OK along the KS border. In fact,
composite radar imagery suggests that the strongest storms are
able to exit Howard County AR, with the trailing line more broken
and less intense as the best forcing shifts NE ahead of the
closed low. However, these should be short- lived, as they race E
across the remainder of the area, exiting by midday. Thus, have
maintained slight chance pops this morning for the Ern 2/3rds of
the area, before cigs rapidly clear from W to E as much drier air
advects E behind the dryline passage. The pressure gradient will
also begin to tighten by mid-morning as the attendant strong sfc
low also over Nrn OK shifts E into Nrn AR this afternoon,
resulting in strong Wrly winds over much of the area. For this
reason, have hoisted a Lake Wind Advisory for the entire forecast
area from 15Z-00Z today with wind gusts to 30 mph possible. Winds
should diminish slightly after sunset, although some higher gusts
will remain possible as an amplifying shortwave trough developing
over the Srn Plains will drive a cold front rapidly SE through the
area in wake of the sfc/upper cyclone passage into the TN Valley.
With the increasing Wrly winds, max temps should climb into the
lower to mid 80s over much of E TX/extreme Srn AR/N LA this
afternoon, and when combined with the very dry air advecting in,
will result in Min RH`s ranging from 20-30%. Fortunately, fuels
remain wet and green in wake of the excessive rains that fell
during the final week and a half of February and first few days of
March, as well as recent rainfall.

The short term progs continue to suggest wrap-around stratus
spilling SE into SE OK/extreme NE TX/SW AR this afternoon behind
the front as it begins to enter the region, which should encompass
much of extreme NE TX/SW AR/N LA by tonight. The pressure gradient
will remain tight through the day Tuesday beneath this stratocu
shield such that another Lake Wind Advisory will likely be needed
as gusty NW winds are expected. While the cold advection will end
by mid-morning Tuesday, the cloud shield should result in below
normal temps areawide, before the cigs begin to scatter out late
in the afternoon into the evening. Winds will also quickly
decouple by sunset as well, as sfc ridging builds SE into the
region. Good radiational cooling will result in min temps Tuesday
night falling into the mid/upper 30s across SE OK/SW AR, with
lower 40s elsewhere. Sfc ridging will linger over the region
Wednesday, resulting in seasonal temps returning with good
insolation and light winds.

A warming trend will commence in earnest Thursday as southerly low
level winds return in wake of the departing sfc ridge, and upper
ridging that will begin to amplify N and shift E into the Srn
Plains. A dry forecast will continue through Friday, although the
medium range progs suggest a weak sfc front will slide S into
OK/NW AR by Saturday morning. However, low level moisture will not
be particularly deep as the front hangs up near or just S of the
Red River of N TX into SW AR Saturday, thus have lowered pops to
slight chance areawide. This front looks to linger across these
areas through next weekend, although convection may increase by
late next weekend/early next week as the upper flow becomes more
SW ahead of broad troughing that looks to develop along and W of
the Rockies.

Prelims to follow below...



SHV  82  48  64  44 /  20  10  10   0
MLU  83  49  63  42 /  20  10  10   0
DEQ  76  44  61  36 /  10  20  10   0
TXK  78  47  62  41 /  20  10  10   0
ELD  81  48  62  40 /  20  10  10   0
TYR  78  45  65  43 /  10   0   0   0
GGG  80  47  64  43 /  10   0   0   0
LFK  84  48  70  43 /  20   0   0   0


AR...Lake Wind Advisory from 10 AM this morning to 7 PM CDT this
     evening for ARZ050-051-059>061-070>073.

LA...Lake Wind Advisory from 10 AM this morning to 7 PM CDT this
     evening for LAZ001>006-010>014-017>022.

OK...Lake Wind Advisory from 10 AM this morning to 7 PM CDT this
     evening for OKZ077.

TX...Lake Wind Advisory from 10 AM this morning to 7 PM CDT this
     evening for TXZ096-097-108>112-124>126-136>138-149>153-



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