Weather

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fxus66 klox 292211 
afdlox 


Southwest California area forecast discussion 
National Weather Service Los Angeles/Oxnard California 
300 PM PDT Friday Aug 29 2008 


Short term...went above MOS with high temperatures for Saturday. 


For tonight and Saturday...the district will remain under the 
influence of southeast flow aloft and will remain open for the 
importation of moisture and instability. The current forecast looks 
good with a slight chance of showers and thunderstorms for the 
mountains...deserts and adjacent valleys. The nam12 also points to 
an upper level disturbance that will graze the southeast portion of 
the forecast area late tonight and Saturday. This disturbance has 
the potential to Widen the threat of showers and thunderstorms to 
other forecast zones...however since this will not be a direct hit 
on the region...will probably avoid including other zones at this 
time. Conditions will tend to be hot and humid...the humidity 
resulting in warmer minimum and slightly cooler maximum temperatures 
with some slight discomfort. 


For Saturday night and Sunday...say goodbye to the dog days of 
Summer as a significant trough for this time of year dives south 
over California. All middle level moisture gets escorted out of the 
region as the winds aloft shift around to the southwest. At the 
surface...increasing onshore flow will import the marine clouds into 
all coastal and many valley sections. Cooler temperatures are 
expected everywhere. Gusty onshore winds will return to the 
mountains and deserts...especially in the afternoon and evening. In 
addition...locally gusty winds look quite possible through and below 
passes and canyons of Santa Barbara County...and in the coastal 
waters...by Saturday evening. 


For Sunday night and Monday...the trough will continue to dominate 
the region with the marine layer deepening enough to reach the 
coastal slopes and producing a little drizzle. The marine clouds may 
be slow to clear...however it may not be a good idea to get to 
detailed with the forecast this far in the future. 


Long term...a gradual warming trend will take place behind the 
passage of the trough. Temperatures will rise to near seasonal 
normals by the end of the week. The GFS and European model (ecmwf) are in good 
agreement. Dry through the period. 


&& 


Aviation...29/1755z. 


Latest amdar soundings indicate marine inversion around 1500 feet 
across the lax basin...while 12z vbg sounding indicated marine 
inversion around 400 feet. Latest satellite shows morning marine 
layer has been vaporized by effects of last night's convection 
over Arizona. Overall...VFR conds will be expected through this 
evening...then some stratus/fog should return to coastal tafs 
overnight. 


Klax...overall...moderate to high confidence in 18z taf. Very 
high confidence in VFR conds through this evening. Moderate 
confidence in return of IFR conds tonight around 06z...although 
arrival time could be later. No wind issues of note. 


Kbur...overall...high confidence in 18z taf. There is a 20% chance 
that some IFR conds could develop across the airfield late 
tonight...around 13z. 


&& 


Lox watches/warnings/advisories... 
gale watch (see laxmwwlox). 


&& 


$$ 


Public...Sweet 
aviation...Thompson 


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