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fxus64 klix 180846 cca 
afdlix 


Area forecast discussion...corrected 
National Weather Service New Orleans la 
346 am CDT Friday Jul 18 2008 


Synopsis... 
weak upper low near Houston early this morning...with surface high 
still over the Appalachians. Middle and high level cloudiness still 
covering west half of area...but this cloud layer appears to be 
rather thin. Precipitation is limited to isolated echoes over the 
coastal waters west of the mouth of the Mississippi River. 


Temperatures generally in the 70s with dewpoints upper 60s to middle 
70s under a light wind regime. 
&& 


Short term... 
disposition of current cloud cover will be the determining factor 
in todays forecast. Weak upper low will continue to move into 
Texas and will not be a direct factor in our weather. 


Model forecast soundings show middle level moisture mixing out this 
morning. Middle level temperatures will warm a couple of degrees to 
around -4c. This may serve to cap the airmass...but it will be a 
close call. Similar conditions expected Saturday. Little doubt 
that some convection will develop...somewhere in the County Warning Area. Will 
areal coverage be greater than 20 percent...that is the question. 
Path of least regret...will go with 20 probability of precipitation for today and Saturday. 


Starting to see indications that Sunday may actually be the dry 
day as upper high forecast to settle over the area on both GFS and 
NAM. Will only carry 10 probability of precipitation on Sunday. 


With warming of lower and middle layers...any areas with nearly full 
sunshine will easily reach the middle 90s each day. 35 
&& 


Long term... 
little change in the extended portion of the forecast as upper 
ridging still the dominant feature. Land-sea interactions will 
provide potential for diurnal convection each day. Temperature 
trends to remain near to above normal for late July. 35 
&& 


Aviation... 
breaks in middle/high clouds and calm winds are allowing light 
radiation fog to form early this morning. Like yesterday...there is 
haze mixed in...so expect one or two taf sites to keep visibility 
restrictions until 14-15z. Rain showers/thunderstorms and rain should remain too isolated for 
mention in the tafs today...but cannot rule out a brief impact on a 
terminal or in the vicinity of a terminal this afternoon. Looking at 
the weekend...status quo for aviation with only isolated mainly 
afternoon shra/tsra...nighttime and early morning light 
fog/haze...and possibly a bit more daytime haze due to a forecast 
middle level inversion with northeast winds. 22 
&& 


Marine... 
excellent boating and fishing conditions are expected to continue if 
you can stand the heat and intense sun. Generally light and at times 
variable winds can be expected through the weekend as a weak 
pressure gradient continues to prevail across the coastal waters. 
Thunderstorms and associated gusty winds will be very isolated. Seas 
will run mostly around one foot with tide ranges around 1.5 feet the 
next few days. Models show a possible tropical system impacting the 
Gulf of Mexico during the early part of next week which may bring 
southeast winds up to near 15 knots over the western waters. 22 
&& 


Preliminary point temps/pops... 
mcb 95 70 94 72 / 20 10 20 10 
btr 95 72 95 74 / 20 10 20 10 
msy 93 76 93 76 / 20 10 20 10 
gpt 92 73 92 75 / 20 10 20 10 


&& 


Lix watches/warnings/advisories... 
la...none. 
GM...none. 
MS...none. 
GM...none. 
&& 


$$