731 
FXUS64 KLCH 061209
AFDLCH

Area Forecast Discussion
National Weather Service Lake Charles LA
609 AM CST Wed Feb 6 2019

.DISCUSSION...
12Z TAFS

&&

.AVIATION...
The somewhat chaotic nature of advecting marine fog and low level
ceiling extent this morning is resulting in categories varying 
between LIFR and MVFR at all sites. This trend is expected to
continue through mid morning with some marginal improvement
expected during the afternoon. However, with forecast guidance 
varying significantly, opted to err more pessimistically by 
maintaining IFR ceilings at all terminals through the forecast
period. Marine fog is once again expected to move inland after
sunset this evening affecting the coastal terminals.

The pressure gradient will continue to tighten today between high
pressure centered across Florida and low pressure moving east out
of Colorado. This will result in southerly winds increasing this
afternoon to 15 to 20 knots with gusts to 25. Winds will lessen 
somewhat overnight, but will remain elevated as the low and an 
associated cold front approach the region.

Jones

&&

.PREV DISCUSSION... /issued 411 AM CST Wed Feb 6 2019/ 

DISCUSSION...
Early morning sfc analysis shows high pressure centered over the
sern CONUS/srn Atlantic coast while low pressure and an adjoining
stationary front are noted from the Ohio Valley to the Red River
Region. The resultant srly low-level flow has maintained a very
moist airmass across the region with temps/dewpoints running
67-71F at this time. Sfc obs also show the slightly elevated winds
keeping fog at bay, while regional 00z raobs/recent 88D VWPs 
showing stronger winds aloft maintaining a solid stratus deck over
the region. Water vapor imagery shows a trof digging over the wrn
CONUS with a wswrly flow aloft over the wrn Gulf Region
maintaining plentiful Pacific moisture through the mid/upper
levels. Perhaps a very weak perturbation is passing the area at
this time as local 88Ds show light returns developing mainly
inland over the past couple of hours with an occasional sfc ob
reporting light rain.

Our recent pattern of warm muggy days looks to persist again today
with perhaps a very slim chance for a shower over the far nwrn
zones in response to a passing weak wave. The main issue again
this morning continues to be fog development...as stated before,
advection fog has yet to really take off while any radiational fog
has been squashed by our light srly flow. Having said that, with
an advisory already in place, would hate to cancel it while we at
least have a risk of some development later this morning should
conditions briefly improve. Highs today will again be very warm
with highs pushing 80 areawide. Fog guidance indicates patchy fog
will again be a concern tonight, mainly near the coast and 
extending across the sern portion of the area.

A strong shortwave dropping out of the Pacific NW will dig the wrn
CONUS trof through the Rockies and into the Plains through
tonight...this in turn will lead to further cyclogenesis over the
Ozarks with the whole system expected to pull a cold front towards the
area on Thursday. Rain chances are expected to increase slightly
over the far nwrn zones after midnight tonight...then elevated
POPs are being carried from west to east staring tomorrow morning
as good lift combines with the copious moisture in place (forecast
soundings indicate PWAT values exceeding 1.5 inches which is over
200 percent of normal). A few storms look possible although
forecast soundings show poor instability/lapse rates. With the
additional clouds/rainfall, forecast highs look a little lower,
but still unseasonably warm in the 70s.

Showers start to diminish across the nwrn zones by late afternoon
as the front begins to sweep through the area. As Canadian high
pressure builds through the Plains, good CAA is expected to surge
into the region with mins tomorrow night progged to range from the
upper 30s nwrn zones to 45-50 sern zones. Friday will be a shock
as temps struggle to hit 50 degrees across a good chunk of the
region...a 25-30 degree drop from Thursday. Also on Friday,
medium-range guidance is indicating a weak ripple in the flow
aloft with perhaps enough moisture to spark a shower or two mainly
across the nwrn 1/2 of the forecast area...lingering into Friday
night.

Small rain chances return to the entire area by late in the
weekend and linger into early next week as moisture return
commences as the high pushes ewd and shortwave energy again passes
aloft. By the middle of the week, the next primary shortwave is
progged to pull another front through the region, bringing an end
to this next round of precip along with a cooldown after highs
again reach the 70s.

MARINE...
Dense fog is being reported over portions of the coastal waters
this morning and guidance continues to indicate this will be an
issue through at least the morning hours. Otherwise a somewhat
elevated srly flow will begin to diminish later today as the
gradient relaxes with the approach of the cold front. Behind the
fropa Thursday night, a round of strong nrly flow is anticipated
to linger into late week. Winds will eventually relax and veer
serly as high pressure builds past the region.

&&

.PRELIMINARY POINT TEMPS/POPS...
AEX  80  64  75  38 /  10  10  70  30 
LCH  77  66  75  45 /  10  10  60  40 
LFT  79  66  79  46 /  10  10  40  60 
BPT  76  66  74  44 /  10  20  60  30 

&&

.LCH WATCHES/WARNINGS/ADVISORIES...
LA...Dense Fog Advisory until 10 AM CST this morning for LAZ041>045-
     052>055-073-074.

TX...Dense Fog Advisory until 10 AM CST this morning for TXZ215-216.

GM...Dense Fog Advisory until noon CST today for GMZ430-432-435-450-
     452-455-470-472-475.

&&

$$


AVIATION...66