Weather

947 
fxus66 klox 071200 
afdlox 


Southwest California area forecast discussion 
National Weather Service Los Angeles/Oxnard California 
500 am PDT sun Sep 7 2008 


New aviation discussion 


Short term... 
marine layer is at 800 feet and onshore east push is 2 mb. Low 
clouds are working their way through the coasts but staying out of 
the valleys except the Santa Ynez. A blanket of dense fog covers the 
central coast and most of the Santa Ynez Valley and a dense fog 
advisory is in effect until 900 am. 586 heights overhead and a shallow 
marine layer will allow for another warm day with the only cool 
temperatures at the beaches. 


A weak trough works it way over northern California tonight and Monday. The lower 
heights and weak lift provided by the trough will rise the marine layer 
and there will be some valley penetration and The Heights will rise enough 
to prevent dense fog in the central coast. Monday will be cooler 
than today especially at the coast with the greater onshore flow but all 
areas should see at least 4 degrees cooling. 


The trough grows and extends SW to so cal Tuesday. Heights fall more and 
onshore flow increases also. This will increase the marine layer 
further as well as continuing the cooling trend. 


Long term... 
both the ec/GFS comparison and GFS ensembles point to fairly 
confident forecast through Friday and then uncertainty sets 
in...although the differences will not greatly affect the forecast. 


The trough remains in place Thursday and the day should be quite 
similar to Wednesday. By Friday the trough moves to the east and a 
small ridge begins to build in. This should lead to a gradual 
reduction in marine layer coverage and a slow warm up in maximum temperatures. 


&& 


Aviation...07/1200z. 
The marine layer was slow to organize tonight...however all coastal 
sites have or will soon become enveloped by the low clouds and fog 
with IFR to LIFR conditions through the early morning. Conditions 
will slowly improve during the middle to late morning. There is a 40 
percent chance of the low clouds and fog lingering around 
klax...koxr and ksba into the early afternoon. 


Klax...fair confidence in low clouds and fog with IFR conditions 
through the middle morning...followed by clearing around 19z although 
there is a 40 percent chance of low clouds lingering into the early 
afternoon...perhaps arriving just after the start of the sea breeze. 
Otherwise...mostly clear skies until the middle to late evening when 
low clouds and fog are expected to return with MVFR to IFR 
conditions. 


Kbur...high confidence in clear skies through the evening. A 60 
percent chance of visibility restriction this morning due to haze. 


&& 


Lox watches/warnings/advisories... 
dense fog advisory (see laxnpwlox). 
Small Craft Advisory (see laxmwwlox). 


&& 


$$ 


Public...rorke 
aviation...Sweet 


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