081 
fxus66 klox 201158 
afdlox 


Southwest California area forecast discussion 
National Weather Service Los Angeles/Oxnard California 
330 am PST Thursday Nov 20 2008 


Short term... 
gradients are still offshore and there are some high clouds wafting 
overhead both of which have conspired to limit the marine layer. 
Clouds are fairly widespread over the central coast but have lifted 
enough to prevent any widespread dense fog. Sba County is low cloud 
free and vta County only has patchy clouds. Areas of clouds in l.A. 
County and some dense fog also. 


All eyes on southern sba County tonight with a strong north gradient 
setting up. Fortunately there is no cold air with the system and the 
upper support is also limited. Wind advisories will likely be needed 
at 300 PM this afternoon but only for 25 to 35 miles per hour with 45 miles per hour gusts 
and 50 miles per hour gusts in the mountains the I-5 corridor will also be breezy 
but most likely below advisory levels...save the always gusty 
whitter peak. The north push should keep the low clouds away. 


The interior of slow and sba counties will see an east push overnight 
from the San Joaquin Valley which will bring a low cloud deck. These 
clouds will linger through the morning. 


Friday the gradients shift to the northeast. It will be a sunny day 
with temperatures near normal...maybe a little warmer on the coast with the 
east push. 


A little Santa Ana sets up Saturday. There is no upper or thermal 
support and this event should be a mild 15 to 25 miles per hour type. The 
northeast push will keep the skies free of low clouds and will also 
allow the coasts to warm nicely. 


Little Ridge pushes in Sunday along with continues offshore flow. 
Which is even weaker than Saturday morning. Temperatures will likely cool 
at the coasts but the higher heights will cause warming inland. There 
is a fly in the ointment with this forecast as the latest NAM/WRF 
solution brings in an eddy and a grip of low clouds to all coastal 
sites. Will have to see if there is any model consistency with this 
forecast and perhaps cloud up the forecast with the 300 PM forecast. 


Long term... 


Medium range models are in better agreement for next week which is 
encouraging. 


Monday will be a fairly lackluster day. The ridge moves off eastward 
and the flow shifts to the SW. There could be a marine layer if the 
middle to high level moisture holds off. It will most likely be just 
partly cloudy as moisture streams in the southwest flow. 


During the Tuesday to Thursday time period an upper low will approach 
Southern California open up and move across. Right now it looks 
likely that there will be rain sometime during this period nailing 
the timing down into 12 hour blocks is still beyond the science. The 
models have been getting better but are still displaying 300 to 400 
mile differences in location of critical features which is the 
difference between a light rain and a serious soaking. The last runs 
really push the maximum dynamics and rain down into San Diego 
County..but the previous run had the maximum more over l.A. County so 
making specific forecasts at this time not the best of ideas. 


That said it looks like the storm track will stay active through 
next weekend with both the ec and GFS forecasting a second event on 
the heals of the first. 


&& 


Aviation... 


20/1200z 


400 foot marine layer is not making much progress inland or up the 
coast. The central coast will have morning clouds through middle 
morning. L.A. County coastal tafs will also likely have clouds and 
since the marine layer is low LIFR visible will accompany the low 
clouds. Building offshore flow should keep the low clouds away 
tonight. 


Klax...only fair confidence in 12-18z portion of taf with a 40 
percent chance of low clouds not reaching the Airport complex. Very 
good confidence in remainder of VFR taf except for a 20 percent 
chance of IFR ceilings after 12z Friday. 


Kbur...very good confidence in VFR taf. 


&& 


Lox watches/warnings/advisories... 
Fire Weather Watch (see laxrfwlox). 
Wind Advisory (see laxnpwlox). 
Gale Warning (see laxmwwlox). 
Small Craft Advisory (see laxmwwlox). 


&& 


$$ 


Public...rorke 
aviation...Bruno 


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