Scientific Forecaster Discussion
fxus64 klch 090028
Area forecast discussion
National Weather Service Lake Charles la
628 PM CST sun Dec 8 2019
00z taf issuance.
intermittent MVFR ceilings this evening at bpt/lch, with MVFR
ceilings expected to prevail after 06z through most of the day
Monday. Intermittent IFR ceilings/MVFR visibility possible between
10-14z at all sites, but not expecting widespread fog as the winds
likely to remain around 5-7 kts along with MVFR ceilings. Winds
expected to increase to near 10-12 kts by 15z, and 15-18 kts with
gusts 20-25 kts by 18z Monday.
Previous discussion... /issued 353 PM CST sun Dec 8 2019/
mild to warm and mostly sunny afternoon across the area, with low
level southerly flow now well established between eastward departing
high pressure and a low pressure trough to the west over the
plains. Aloft, westerly flow prevails across the region downstream
of an approaching western Continental U.S. Trof.
Few big changes of note made to the forecast this afternoon. Warm
air advection regime already established progged to intensify
tonight into Mon, yielding warmer overnight/afternoon temperatures
and an increasing influx of Gulf moisture. Some guidance pointing
toward fog tonight, but believe boundary layer winds will be
elevated enough to inhibit any significant visibility reductions.
Temperatures tonight will be around 10-15f above seasonal normals.
Mostly cloudy and warm on Monday, with highs reaching the upper
70s to near 80.
Areas of light rain/isolated showers are possible by the
afternoon and evening amid increasing lift, with widespread
showers and isolated thunderstorms expected after midnight as the
front begins to push through the area. Rains will continue through
the day on Tuesday with the upper trof axis still out west and
isentropic ascent continuing atop the shallow cold-air wedge.
Bulk of rains end west-east Tuesday night with the passage of the upper trof
axis and punch of drier air, though at least small chances will
linger into Wednesday morning, especially southeast half or so of the area.
Much colder air will intrude in the wake of the front as it passes
through on Tue, with lows Tuesday night expected mostly in the
mid/upper 30s away from the coast. Highs Wednesday will reach only the
This cold airmass will be slow to modify, with only slow and
steady warming each day through the end of the week. Still some
spread global models regarding a second upper trof digging into
the northwest Gulf Coast region on Fri, though the trend favors a drier
solution shown by the European model (ecmwf) and CMC. Carried very small pops over
eastern areas Thursday night into Fri, similar to the previous
forecast. Warming trend continues and accelerates through the
weekend with southerly winds returning.
a modest onshore flow will prevail until a cold front pushes
through the coastal waters on Tuesday, with strong north winds and
building seas expected in the wake of the frontal passage.
Widespread showers and possibly a few thunderstorms are expected
to develop Monday night and continue on Tuesday with the passage
of the front. Winds and seas will subside Wednesday night into
Thursday, with offshore winds persisting through the end of the
Preliminary point temps/pops...
aex 55 78 50 57 / 10 30 90 90
lch 59 78 59 66 / 10 30 80 90
lft 57 79 61 69 / 10 30 70 80
bpt 61 78 58 63 / 10 20 80 90