Scientific Forecaster Discussion
fxus64 klch 281116
Area forecast discussion
National Weather Service Lake Charles la
616 am CDT Tue Mar 28 2017
Aviation...MVFR to IFR conditions are ongoing this morning,
however ceilings and vis will improve through the morning. VFR
conditions are expected through the afternoon, however low
ceilings are expected again tonight. South to southeast winds will
be gusty at times today.
Previous discussion... /issued 511 am CDT Tue Mar 28 2017/
generally benign weather on tap for today as ridging between a
departing shortwave trof over the Ohio River valley and a digging
upstream trof west of The Four Corners slides overhead. Expect a
warm and humid afternoon underneath a fair amount of cloud cover,
with south winds increasing and becoming a bit breezy over
coastal southeast Texas/SW la. Another warm and muggy night tonight with
winds remaining elevated, especially along the coast and over the
western zones as a 30-40kt low level jet begins to overspread the area with the
approach of the upstream trof.
Wednesday is expected to start out relatively quietly owing to
considerable cinh depicted in area forecast soundings. This is
expected to begin changing by afternoon, however, as more
favorable lapse rates begin to overspread the area along with
falling heights and a split jet structure as the upper trof enters
the Texas Panhandle. Thunderstorms are forecast to develop/ over East Texas by
late afternoon, then subsequently spread/develop east of the Sabine
River during the evening. Progged kinematic/thermodynamic
parameters support a severe weather risk, with all modes possible.
Thunderstorms will continue to slowly spread/develop east through the
overnight hours and into Thursday morning, with activity expected to
push east of the area during the afternoon with the passage of a
weak cold front. Have continued with a mention of severe thunderstorms in the
forecast for the Wednesday afternoon through Thursday afternoon period.
Dry weather is expected in the wake of the frontal passage Friday and
Sat, with rain chances returning Sat night with the approach of
another upper level trof. Global models continue to be divergent
with their handling of this feature, though at this time a slower
and less progressive solution is favored, keeping good rain
chances in the forecast Sunday and Monday.
light to modest south winds are forecast to begin strengthening
today as a low pressure system emerges east of The Rockies. Have
headlined scec for the Gulf waters within 20 nm west of Cameron
and all of the Gulf waters beyond 20 nm for late this afternoon,
then switched to a scy for these areas this evening. Scec for the
remaining Gulf waters east of Cameron this evening. Brisk south
winds will continue Wednesday as this feature tracks eastward across the
plains, subsequently pulling a frontal boundary through the
coastal waters Thursday afternoon/evening. Additional hazard
headlines/products may be needed for Wednesday. A brief period of
offshore flow will follow the frontal passage, with south winds
returning by Friday.
Preliminary point temps/pops...
aex 83 66 81 68 / 10 10 30 80
lch 81 67 81 69 / 10 10 40 80
lft 84 70 84 72 / 10 10 20 60
bpt 83 71 81 68 / 10 10 70 70
GM...Small Craft Advisory from 7 PM this evening to 7 am CDT
Wednesday for gmz450-470-472-475.
Small craft exercise caution from 4 PM CDT this afternoon
through this evening for gmz450-470-472-475.
Small craft exercise caution from this evening through Wednesday
morning for gmz452-455.