543 
fxus66 klox 131009 
afdlox 


Southwest California area forecast discussion 
National Weather Service Los Angeles/Oxnard California 
310 am PDT Monday Oct 13 2008 


Short term... 
grads are about -4 mb in each direction and should be around -5 mb 
by dawn. NAM/WRF seems a little overdone with the upper support as 
it indicates about 45 knots of low level support at 9z but 9z observation were 
much less. This is actually fairly normal as WRF does have a history 
of over doing low level winds in these offshore events. Still 
forecast looks on track with high end wind advisories and low end 
wind warnings. Winds peak from 12z to 18z and then relax some...but 
the winds will intensify overnight tonight and be at the same 
values again Tuesday morning. Tuesday forecast calls slightly more 
offshore gradients but slightly less upper support which should 
balance out. Continuous warm air advection will make temperatures in the 
coasts and valleys today warm and Tuesday hot but will also serve to 
but some brakes to the winds which would simply be howling if there 
were any cold air advection with this system. Mountains and deserts 
will warm today but only to normal and then a little above normal 
Tuesday. 


The air is very dry and with the winds low temperatures will be very 
mixed. Wind sheltered areas will drop into the 30s in the interior 
while windy areas will likely stay in the 60s. Due to rising heights 
lows should stay warm enough to limit the frost but middle 30s will be 
the rule across interior slow and sba counties. 


Wednesday will be a Santa Ana lite day. Look for 15 to 25 miles per hour winds 
with some gusts to 35 miles per hour temperatures will continue above normal. 


Long term... 
ec and GFS in OK agreement through Saturday morning and then rapidly 
diverge.GFS ensembles hold together into Sunday. Not much to say 
about Thursday and Friday enough diurnal offshore push in the morning to 
keep the low clouds away. Temperatures will cool slowly as heights fall slowly 
and offshore flow dwindles. 


A trough approaches the coast on Saturday and flips the flow onshore 
heights also should fall through the day so a good cool down will 
occur. A case could be made for some sort of marine layer to form 
but for now will keep things clear. 


If you believe the GFS it will be much cooler with a pretty good 
marine layer on Sunday but not so if you go with the ec solution. For 
now continued with the cooling trend but did not bring low clouds in 
although it is a good possibility. 


&& 


Aviation... 


12/1100z 


High confidence in VFR conditions everywhere through Tuesday 
morning. Low level wind shear and MDT turbulence will be likely at times over and 
near to the mountains 


Klax...high confidence in ceiling and visibility unlimited taf. 


Kbur...high confidence in ceiling and visibility unlimited taf. Light-MDT turbulence from surface to 
070 likely for the next 30 hours. 


&& 


Lox watches/warnings/advisories... 
red flag warning (see laxrfwlox). 
Freeze warning (see laxnpwlox). 
Wind Advisory (see laxnpwlox). 
Frost advisory (see laxnpwlox). 
Small Craft Advisory (see laxmwwlox). 
Marine weather statement (see laxmwslox). 


&& 


$$ 


Public...rorke 
aviation...Kaplan 


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