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Area forecast discussion 
National Weather Service Lake Charles la
1203 am CST Thursday Jan 29 2015

went ahead and issued a dense fog advisory for lower southeast Texas and
far SW la. Visibilities at southeast Texas airports have already lowered to one
quarter of a mile and these conditions are expected to persist
through the night. Fog has also developed across SW la...with visibilities
currently fluctuating but expected to lower to around 1/4 mile as
the night progresses. Conditions are expected to improve by middle-
morning Thursday. 24


Previous discussion... /issued 1130 PM CST Wednesday Jan 28 2015/

for the 29/06z taf issuance.

surface ridge is east of the region with light southerly winds
helping to bring some shallow moisture back into the region. Short
wave producing some high level clouds have pushed off to the east
also leaving behind clear skies. With the clear skies and light
winds...air temperatures should cool to dew points with some fog
formation...especially over southeast Texas and southwest
Louisiana where air temperatures have already cooled below what
the evening dew points were...and with that...visibility down to
LIFR at kbpt and bouncing between MVFR/IFR at klch. Expect kbpt to
experience LIFR conditions for the overnight into early Thursday
morning...with klch also settling in for mainly LIFR conditions
after 29/09z. The other taf sites that have seen less return flow
moisture will likely experience MVFR conditions overnight...with
the brief possibility of IFR. With increasing winds and daytime
heating...any fog should lift by 29/15z...with VFR conditions
prevailing for the remainder of the day. A weak cold front will
move through at the end of the taf period with a switch to
northwest winds and cloud deck around 5k feet moving with the


Previous discussion... /issued 950 PM CST Wednesday Jan 28 2015/

a quiet night underway with high pressure east of the
region...allowing southeasterly winds to bring increasing low level moisture
over the area. Dewpoints across SW la and southeast Texas are in the lower
50s with middle and upper 40s across eastern portions of the area.
Overnight lows are expected to run about 5-10 degrees warmer than
last night with lows in the lower to middle 50s across all but the
eastern-most zones where temperatures will be in the upper 40s/near 50.

With lt winds across the area and dewpoint depressions
narrowing...fog should begin developing by midnight. Fog is
expected to begin developing across lower southeast Texas/SW la initially...then
increase in coverage further north and east across the area through
the night. Sref probabilities as well as NAM and hrrr guidance
indicate the potential for visibilities less than one mile...and
dense fog could be possible in a few locations. Will continue to
monitor trends for the possibility of a dense fog advisory.


Preliminary point temps/pops...
klch 52 72 47 59 / 0 0 10 10
kbpt 55 72 50 61 / 0 10 10 10
kaex 51 72 43 58 / 0 0 10 0
klft 50 74 48 60 / 0 0 10 10


Lch watches/warnings/advisories...
la...dense fog advisory until 8 am CST Thursday for Calcasieu-West

Texas...dense fog advisory until 8 am CST Thursday for Hardin-Jefferson-
Orange-southern Jasper-southern Newton.




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