Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Lake Charles la
1210 PM CDT Thursday Oct 8 2015
18z taf issuance.
middle/high scattered/broken clouds prevail...VFR expected. L&v winds expected
Thursday the period. Weak instability may generate isolated rain showers over c la
this afternoon...thus the vcsh at that terminal. Vcsh expected by
15z Friday regionwide ahead of an approaching front...along with
lower cloud bases ~4-5k this afternoon. Frontal passage not expected until
Previous discussion... /issued 1024 am CDT Thursday Oct 8 2015/
middle and high level clouds moving up the Texas coast into
southeast Texas and southwest Louisiana. This is well
advertised in the zone forecast package. Temperatures are
forecast this afternoon to be lower than yesterday...and
looks to be because of said cloud cover spreading across area.
No organized convection today but cannot rule out a renegade
shower or two. Only change to forecast package will be to remove
the patchy fog out of morning forecast. No other changes needed.
The atmosphere is relatively in a benign state. 06
Previous discussion... /issued 618 am CDT Thursday Oct 8 2015/
Aviation...patchy fog is occurring across the area this morning
with the lowest visible occurring across lower Acadiana. The fog will
burn off over the next few hours as temperatures warm after sunrise. VFR
conditions are then expected through the rest of the day and
through the evening, however patchy fog is expected to redevelop
toward Friday morning. Light winds generally from the southeast can be
Previous discussion... /issued 509 am CDT Thursday Oct 8 2015/
latest upper air analysis/water vapor satellite imagery showed an
upper low south of The Four Corners...with downstream ridging over
the northwest Gulf Coast region. Upstream shortwave energy was
just starting to spill into the intermountain west.
Fair amount of Pacific moisture streaming overhead evident in thick
cirrus noted on infrared satellite imagery. Low level moisture remains quite
limited however as is evident on 00z klch radiosonde observation...and is prognosticated to
remain that way per model time heights amid an easterly low to middle
Surface pattern remains generally non-descript...though after
reviewing surface observation and visible satellite imagery from
yesterday...it appears that a weak inverted surface trough has pushed
westward into parts of central la. Patchy fog noted over south central
la...and may update the pfm/zone forecast product shortly if the area of lower visibilities
Upper ridging over the region is forecast to begin flattening out
today as the upper low out west sinks to the south and the
upstream shortwave energy dives through the intermountain west and
into the plains. High resolution and global models are depicting
at least light quantitative precipitation forecast values this afternoon...centered mostly over
the northern half or so of the area in vicinity of of where the weak surface
trough and highest precipitable waters will reside. Low end probability of precipitation were added for
isolated shower potential...but otherwise...a generally warm
albeit cloudy day is in store.
The aforementioned shortwave is still slated to send a weak front
through the area on Friday...with low end probability of precipitation retained as better
moisture/lift will be displaced to our NE. Quick shot of cooler/drier
air expected in the wake of this front over the weekend...with
temperatures/dewpoints rising Monday ahead of another approaching
shortwave and associated front. These systems appear similarly
moisture limited...so only carried a small pop Monday night into Tuesday.
light winds and low seas can be expected into the weekend as weak
high pressure prevails over the area.
Preliminary point temps/pops...
aex 68 90 64 85 / 10 20 10 0
lch 70 86 69 86 / 10 20 10 10
lft 68 88 68 87 / 10 20 10 10
bpt 70 87 69 88 / 10 20 10 10