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Area forecast discussion 
National Weather Service Lake Charles la
1253 PM CDT Friday Sep 19 2014

Discussion...
for the 18z taf package.

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Aviation...
VFR is expected to prevail. Kept thunderstorms in the vicinity/vcsh at the I-10 terminals
with a west-northwest to east-southeast oriented moisture axis still in place...though this
should continue to be shunted southward through the day. Some light MVFR
visibility restrictions are possible overnight/early Saturday
morning...so tempo groups were inserted at all sites.

13

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Previous discussion... /issued 1116 am CDT Friday Sep 19 2014/

Update...
regional radar mosaic depicts an area of light to moderate
rain...with a few embedded heavier cells and isolated thunderstorms...across
southeast Texas into the northwest Gulf. Most of this activity was occurring west
of the County Warning Area toward Houston...while a few isolated showers have
recently developed lower southeast Texas and along the S cntl la coast.
This activity was occurring along a zone of low level convergence
combined with a trough aloft over the region. Recent WV imagery
shows drier air moving into the region from the north and this
should help to limit rain chances over inland areas north of I-10.
The greatest chance for showers and storms will be over the coastal
waters...with scattered convection possible along and S of I-10. Main
axis of moisture and convection will shift south through tonight
as northerly flow aloft brings drier air over the area.

Made only some minor adjustments to current forecast based on latest
guidance. Probability of precipitation were changed slightly based on recent hrrr
runs...while hourly temperatures...dewpoints and winds were tweaked to
reflect recent observation and trends. 24

Previous discussion... /issued 628 am CDT Friday Sep 19 2014/

Aviation...

A stationary front stretches through Freeport to Naples Florida
this morning. Associated frontal showers and a few thunderstorms
are found across the coastal waters of southwest Louisiana and
southeast Texas.

Convective activity is expected to remain over the coastal waters
and adjacent coast for today.

Jt

Previous discussion... /issued 409 am CDT Friday Sep 19 2014/

Discussion...radar depicting a few showers over our near coastal
waters...with further development inland of Galveston Bay.
Activity appears to firing along low level 850 mb trough axis and
associated convergence per latest RUC. Infrared imagery showing
widespread middle-level altocu over the forecast area...while water
vapor continuing to show considerable middle and upper moisture
streaming in from the west northwest compliments of the remnants of
Odile. Water vapor further shows moisture beginning to be shunted
southward as a deep layer northerly flow develops between deepening
southeast Continental U.S. Trough and amplifying south Continental U.S. Ridge.

For today through the weekend...main shower and thunderstorm
activity is expected to be over the near coastal waters and
immediate coast today in line with axis of deep tropical moisture.
Drier air punching in from the north as mentioned will overspread
the inland area this afternoon and tonight resulting in a
generally dry weather pattern for Saturday and Sunday.

Models still pinging on our next frontal passage coming Monday. Did increase
probability of precipitation slightly during this time-frame with a little more available
moisture to be in place with passage. Blended temperatures Post-frontal passage
Landing between the GFS...cooler...and the European model (ecmwf)...warmer.

Marine...considerable shower and thunderstorm activity can be
expected over the northwest Gulf as an upper level trough advances
southeast across the region. Much drier high pressure will then
becoming reestablished with only isolated convection expected
through the weekend. A light to moderate easterly flow will
prevail. A cold front is expected to advance into and through the
near coastal waters Monday. This feature will bring the
possibility of a few more thunderstorms with its passage...and an
offshore flow in its wake. 23

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Preliminary point temps/pops...
klch 85 72 87 72 / 30 10 20 10
kbpt 84 73 85 73 / 40 20 20 10
kaex 88 69 89 69 / 20 10 10 10
klft 86 72 88 72 / 30 10 10 10

&&

Lch watches/warnings/advisories...
la...none.
Texas...none.
GM...none.

&&

$$

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