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fxus66 ksgx 200351 
afdsgx 


Area forecast discussion 
National Weather Service San Diego California 
900 PM PDT Friday Mar 19 2010 


Synopsis...fair weather will dominate this weekend as high pressure 
and weak offshore flow prevail. Temperatures will be a little above 
seasonal normals. Only patchy low clouds and fog are expected 
tonight near the coast. A trough of low pressure will move through 
around Tuesday and bring cooler weather...increasing clouds and some 
gusty winds to the mountains and deserts. Weak high pressure will 
follow and bring slight warming. 


&& 


Discussion...for southwest California including San Diego... 
Orange...southwest San Bernardino and West Riverside counties. 


Skies were clear and winds were light this evening. Pressure 
gradients were onshore...around 4-5 mb from the coast to the lower 
deserts...but that should become weak offshore by early Saturday. 
Acars soundings show that the inversion has become surface 
based...so any stratus/fog that develops will be near the immediate 
coast. The offshore flow from early Saturday through early Sunday 
will likely keep the stratus away then. Temperatures will be a little lower 
over the mountains/deserts due to some cold air advection from the east/NE 
and a little warmer near the coast. Areas that were near 80 in the 
inland Empire due to a period of offshore flow Friday will have 
similar temperatures. Sunday looks slightly warmer in most areas. 


Seasonally progressive pattern will mean that the ridge overhead 
this weekend will shift east to the Great Plains by Monday while an 
east Pacific trough will move through here sometime late Monday or 
Tuesday. Models have been fairly consistent with a closed low moving 
around the base of the trough into north Baja California. Moisture will be limited 
with this system and mostly at the middle levels. So...I have kept 
precipitation out of the forecast for early next week. There could be a 
brief period where the marine layer...which will redevelop late 
Sunday...could become deep to produce quite a bit of cloudiness...in 
addition to some middle-level clouds. Some instability is 
expected...some cumulus will be possible over the mountains Tuesday. 
Monday/Tuesday will have temperatures a little below normal...then mostly near 
normal temperatures are expected Wednesday-Friday as semi-zonal west flow develops 
with occasional short waves going by to our north. 


&& 


Aviation... 
200315z...VFR with mostly unrestricted visibilities. Except near 
immediate coast after 10z-12z areas of low clouds based 400-800 feet 
mean sea level with tops around 1000 feet mean sea level Saturday morning. 


&& 


Sgx watches/warnings/advisories...none. 


&& 


$$ 


Public...Maxwell 
aviation...ecc