Scientific Forecaster Discussion
fxus64 klch 152338
Area forecast discussion
National Weather Service Lake Charles la
538 PM CST sun Dec 15 2019
prevailing VFR cigs across the region are expected to gradually
lower to MVFR over the next couple of hours with the loss of
daytime heating. Winds are also expected to weaken somewhat, but
will remain strong enough to prevent any fog formation overnight.
Isolated to scattered showers will develop beginning after
midnight in advance of an approaching cold front that will move
through the area from mid morning through late afternoon.
Scattered to numerous thunderstorms will develop ahead of the
front with a squall line expected to form on the leading edge.
Damaging winds and large hail will be possible within the squall
line. Winds behind the front will turn out of the northwest and
increase once again late Monday.
Previous discussion... /issued 355 PM CST sun Dec 15 2019/
partly to mostly cloudy skies this afternoon did
not do enough to hinder the strong warmup to above
normal temperatures. In fact...several spots did manage
to hit 80 degrees this afternoon including Beaumont...Lake
Charles...Jasper and esler field. The average high is around
64 degrees...so that is 16 degrees higher than normal.
The rapid warmup began right after the fog burned off across the
area in response to a falling pressure across the region due to an
approaching strong upper level storm system which will move into
the plains on Monday. Sustained winds were mostly below 20 knots
in most locations...however the real story was the gusty
southerly winds which reached up to 32 mph in parts of Louisiana.
Gusty winds in the upper 20s were common.
Going forward now...looks like Gulf moisture moisture will
continue to feed into southeast Texas and Louisiana on continued
light to moderate southerly flow tonight. There could be some
patchy fog again tonight after midnight but the airmass will
likely continued to be stirred up...therefore...banking on low
clouds to be the main concern tonight along with possible showers
and thunderstorms later tonight as the system approaches.
The Storm Prediction Center has our area in a slight to enhanced
risk areas overnight into Monday as the sounding profiles suggests
rapid destabilization and elevated helicities which will likely
transition Ordinary thunderstorms into supercells ahead of the
line Monday morning into the afternoon and evening with qlcs line
of storms with the actual front. In this area...we do see rapid
spinup of brief tornadoes within qlcs lines along with damaging
winds. The zone forecast...and other products along with our
digital grids will include this severe weather wording on Monday
to better advertise the threat.
Once the front moves across the area on Monday and Monday night...
we do expect the rain to end behind the front with strong high
pressure building to the region.
Stable weather will stick around until early morning Friday
before the next system and front approaches the area. Rain chances
will briefly spike on Friday but the frontal passage Friday night
should allow for high pressure and stable conditions to settle in
just in time for the weekend next week.
As for temperatures...look for one more day on Monday for above
normal temperatures in the mid to upper 70s areawide. Then...the
remainder of the week will be below normal in the mid to upper 50s
with a slight warmup to near normal temperatures by the very end
of the 7 day period ending Sunday. Lows in the lower 30s can be
expected Wednesday and Thursday mornings northern areas north of
the i10 corridor. However...we should stay above freezing for
overnight lows along and south of the I-10 corridor...perhaps in
the mid 30s for lows.
went ahead and issued a gale watch for the nearshore and outer
waters Monday night into Tuesday along with Small Craft Advisory
conditions for the lakes and bays as the cold front sweeps across
the coastal waters and strong high pressure builds in. Winds and
waves will be too high for small craft during the gale watch
Preliminary point temps/pops...
aex 65 76 38 52 / 50 100 40 0
lch 67 78 41 53 / 50 100 40 0
lft 66 78 43 51 / 40 100 70 0
bpt 68 77 41 54 / 50 100 30 0
GM...gale watch from Monday evening through Tuesday afternoon for
Small craft exercise caution until 6 PM CST this evening for
Small Craft Advisory from 6 PM Monday to 6 PM CST Tuesday for