518 
fxus64 kshv 231134 
afdshv 


Area forecast discussion 
National Weather Service Shreveport la 
534 am CST Monday Nov 23 2009 


Discussion... 


Surface high pressure over the four state region early this 
morning along with light surface winds will allow for a cool and foggy 
start to the morning commute. Surface visibilities will vary 
depending on where the fog will be most dense. Low clouds trapped 
below a low level inversion will also provide for a cloudy sky for 
most of the region this morning. Where the sky was clear to partly 
cloudy the fog may become more dense by sunrise and continue into 
the middle morning around 9 am. Water vapor loop this morning showed 
our next trough spreading across The Rockies. As this upper system 
moves out into the plains it will send a surface low east with a 
cold front trailing south. The front will be approaching the 
northwest sections of the forecast area affect zones in northeast 
Texas...southwest Arkansas...and southeast Oklahoma after midnight and 
before daybreak Tuesday...then across the remaining zones during 
the day. Gulf moisture will be returning ahead of the front but 
not expecting much thunderstorm development and will keep wording 
in the zones as showers. With the front quickly moving east of the 
Mississippi River in the late afternoon and early evening...will 
end rain chances prior to midnight. Surface high pressure will 
build into the four state region after frontal passage providing 
cooler and drier air along with clearing skies. Another 
reinforcing supply of cool and dry air arrives Wednesday night 
into Thursday. Temperatures will be dropping into the 30s near 
Thanksgiving with some areas dipping to near or below freezing. 
Some locations across the northern parts of the forecast area 
may see freezing temperatures Wednesday night...Thursday night and 
Friday night. High pressure will move east during the early start 
to the weekend with moisture from the Gulf returning around its 
back side setting up our next chance for showers and possibly 
thunderstorms by late Saturday night into Sunday with the arrival 
of the next cold front. Have stayed near the GFS and gfsx MOS 
temperatures through the short and long term. /06/ 


&& 


Aviation... 


Starting out the morning with patchy fog at the area terminals with 
mostly MVFR/IFR visibilities but closer to sunrise...some of these 
locations could fall to LIFR/vlifr visibility categories. This will be a 
last minute call concerning the 12z taf package. Concerning 
ceilings...will likely go with prevailing LIFR ceilings with a slow 
improvement to VFR conditions at mlu/eld terminals and a more rapid 
improvement after sunrise at the East Texas terminals. Cold front 
approaches the region from the west late tonight but should remain 
just west of our East Texas terminals by 24/12z. Will likely see some 
patchy fog with low ceilings once again ahead of the front overnight 
and will thus make this mention in the 12z taf package this morning. 


&& 


Preliminary point temps/pops... 
shv 71 52 67 41 65 / 0 30 40 10 0 
mlu 69 49 69 42 65 / 0 20 40 20 0 
deq 67 48 64 33 61 / 0 40 30 0 0 
txk 69 51 65 38 63 / 0 30 30 0 0 
eld 70 50 65 40 65 / 0 20 40 20 0 
tyr 72 52 65 41 63 / 0 30 30 0 0 
ggg 72 51 66 40 64 / 0 30 30 0 0 
lfk 74 51 68 40 65 / 0 20 40 10 0 


&& 


Shv watches/warnings/advisories... 
Arkansas...none. 
La...none. 
OK...none. 
Texas...none. 
&& 


$$ 


06/13