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Area forecast discussion 
National Weather Service Shreveport la
405 PM CDT Tuesday Sep 16 2014

Discussion...
only very isolated convection has developed over deep East Texas/west-central
la this afternoon...along and S of the weak shortwave which has
only slipped a little farther S into East Texas/north central la. As
expected...the weak seabreeze still remains to our S over southeast
Texas/scntrl la...and should remain that way as the trough continues
to slip southeast. Have maintained slight chance probability of precipitation tonight for areas
S of I-20...but have also noted a few towers building over the
higher terrain of southeast OK/west-central Arkansas per visible satellite
imagery...and have also included isolated thunder mention for
these areas this evening as well. The afternoon surface analysis also
indicates a weak surface front over NE OK/central and eastern Arkansas this
afternoon...but its slow south-southwest progress will cease by late
tonight...just to the NE of the area. This boundary may begin to lift
back north Wednesday...with better convective development expected
farther to the SW over East Texas/west-central la as surface boundaries from this
afternoon/S convection...and increasing Pacific moisture from ts
Odile spreads southeast across Texas.

Odile itself has shifted over the northern Gulf of California...and
will enter northwest old mx later tonight...before shifting NE across southern
Arizona/nm through Thursday morning. Could see an increase in
convection over much of Texas Thursday as shortwave energy digs southeast
ahead of the amplifying ridge aloft over The Rockies. At this time...the
heaviest rainfall should remain just to the west of the region...but
have increased probability of precipitation to middle chance over the SW sections of East Texas
which will be most affected by the deepening moisture from Odile.
In addition...the WRF/European model (ecmwf) indicate the weak surface front over Arkansas
backdooring SW again into the region Thursday afternoon...which
may focus scattered convection especially as the best instability is
realized during the afternoon. Much of the convection should wind
down Thursday night with the loss of heating...and as drier air
begins to entrain S beneath the shortwave passage.

Afterwards...The Rockies upper ridging will build east over the Southern
Plains Friday through much of the weekend...resulting in above
normal temperatures and dry conditions over the region. Still quite a few
of discrepancies with the GFS/European model (ecmwf) with what they do with the
remnants of Odile...with the European model (ecmwf) actually hanging this
disturbance up over Kansas/OK for much of the weekend/early next week.
The GFS remains more progressive but keeps the heaviest rainfall
farther west across central OK/Texas this weekend...before longwave
troughing over the eastern Continental U.S. Digs southeast but allows slightly cooler
air to spill S into the region. For now...have maintained low
chance probability of precipitation early next week...before cooling temperatures back down to
near/slightly below climatology by the end of the extended.

Prelims to follow below...

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&&

Previous discussion... /issued 109 PM CDT Tuesday Sep 16 2014/

Aviation...
for the 16/18z tafs...VFR conditions expected to prevail for most
of this taf period despite several cloud layers affecting our taf
sites this afternoon. Middle and high clouds continue to overspread
the region due to weak westerly flow pattern aloft. Meanwhile...cumulus
field is quickly expanding nwrd from the la/Texas coast as sea breeze
convection is enhanced by low level convergence with a weak back
door front just north of the txk/eld terminals. Have included thunderstorms in the vicinity
at all terminals for later this afternoon through early evening
with the best chances of thunderstorms and rain at the lfk terminal. Winds will be
light and mostly variable through the taf period but still favor
an easterly component. The other concern for tonight/Wednesday morning
is fog developing in this very moist air mass and winds near calm.
Visibilities may drop to MVFR and possibly IFR for a few hours by sunrise
but quickly improve thereafter. /19/

&&

Preliminary point temps/pops...
shv 71 92 72 91 69 / 10 20 20 30 10
mlu 69 91 70 89 67 / 10 10 10 30 10
deq 66 89 69 87 66 / 10 10 20 30 10
txk 68 90 71 88 67 / 10 10 20 30 10
eld 66 90 70 87 66 / 10 10 10 30 10
tyr 71 90 72 88 70 / 10 30 30 40 20
ggg 71 91 71 89 70 / 10 30 30 30 20
lfk 72 90 73 88 72 / 20 40 30 40 20

&&

Shv watches/warnings/advisories...
Arkansas...none.
La...none.
OK...none.
Texas...none.
&&

$$

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