Scientific Forecaster Discussion

NWS Discussion
			
				

Area forecast discussion 
National Weather Service San Diego California 
330 am PDT Sat may 25 2013 


Synopsis... 
a trough of low pressure will remain near the West Coast into next 
week. This will maintain onshore flow with temperatures a little 
below average...with areas of night and morning coastal low clouds 
and fog extending into the inland valleys...and with gusty west 
winds in the mountains and deserts each late afternoon through late 
evening. 


&& 


Discussion...for extreme southwestern California including Orange... 
San Diego...western Riverside and southwestern San Bernardino 
counties... 


Short term (today through Memorial day)... 
a trough of low pressure will remain along the West Coast will 
maintain onshore flow. This will keep high temperatures a little 
below average. The marine layer will remain near 3000 feet deep with 
areas of night and morning coastal low clouds and fog extending into 
the inland valleys. The onshore flow will bring locally gusty west 
winds to the mountains and deserts each late afternoon through late 
evening. Winds this afternoon and evening should be slightly 
stronger than Friday...enough for isolated gusts to around 50 miles per hour in 
the windiest locations in the northern Coachella Valley and near the 
ridge tops of the San Diego County mountains. Winds a little 
stronger for Sunday...then a little stronger Monday than on Sunday. 
This would bring advisory strength winds for Sunday with a little 
greater coverage of advisory strength winds for Monday. 


&& 


Long term (tuesday through friday)... 
the European model (ecmwf) has trended slightly weaker with the trough of low 
pressure moving inland through California on Tuesday. While still 
more amplified than the other guidance...it is much closer in 
amplitude to the other guidance. Also with the slight reduction in 
amplitude...500 mb heights with the most amplified solution only 
fall to around 570 dm...usually not sufficient for rain in Southern 
California. The most likely scenario now...if any precipitation were 
to occur at all...would be for some light precipitation along and 
west of the mountains from the marine layer. Otherwise...the main 
impact of the trough passage will be stronger onshore flow for 
advisory strength west winds in the mountains and deserts and some 
minor additional cooling. Modest warming for Wednesday through 
Friday as 500 mb heights slowly rise. 


&& 


Aviation... 
251030z...coast/valleys...areas of stratus will have bases around 
2000-2500 feet mean sea level and tops to 3000 feet mean sea level...with clearing between 16z 
and 18z. Most visible will remain above 5 miles. Stratus will redevelop 
along the coast 00-02z this evening and spread through the valleys 
overnight. Slower clearing is expected Sunday. 


Mtns/deserts...mostly clear with unrestricted visible through Sunday. 
Gusty surface west winds to 35 knots will develop Sunday afternoon over 
the Desert Mountain slopes and through/east of San Gorgonio Pass. 


&& 


Marine... 
astronomical high tides to 7.2 feet and below normal low 
tides...with swings of 8.9 feet...will combine with slightly above 
normal surf to bring a small chance of minor coastal flooding 
through Memorial Day. The highest high tides will take place in the 
late evenings and the lowest low tides will be in the early 
mornings. Strong rip currents will continue through Memorial 
Day...partly due to the swings in The Tides. 


&& 


Sgx watches/warnings/advisories... 
California...none. 
Pz...none. 


&& 


$$ 


Public...17 
aviation/marine...Maxwell