000 
fxus66 ksgx 232026 
afdsgx 


Area forecast discussion 
National Weather Service San Diego California 
125 PM PDT Wed may 23 2018 


Synopsis... 
a deep trough moving into the region will bring more may gray and 
cooler than average weather through Sunday. There may be areas of 
light rain or drizzle in the deep marine at times the next few 
mornings. Gusty west winds will continue in the mountains and 
deserts, strongest on Friday and Saturday. The trough weakens Sunday 
for better clearing, warmer days, and a shallow marine Monday and 
Tuesday. Another trough will bring back cooler weather and a deep 
marine layer next Wednesday and Thursday. 


&& 


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


The inversion was stronger this morning (14c at 850 mb) compared to 
Tuesday morning (10c at 850 mb) and that resulted in slower clearing 
today. The inversion will weaken this afternoon and clouds will mix 
out of most of the valleys, but clearing may not occur at all areas 
within 5 miles of the coast, especially in Orange County. Marine 
layer clouds will spread back inland this evening and reach the 
foothills overnight with clouds and fog in the Cajon Pass and the 
San Gorgonio Pass. There may be areas of drizzle tomorrow morning. 


On Thursday night a trough deepening off the California coast will bring 
back stronger onshore flow and an even deeper marine layer to around 
5000 feet. Drizzle is again possible Friday morning. On Friday night 
and Saturday, a 500 mb vort Max rounding the base of the trough will 
deepen the marine layer even further, which may trigger areas of 
light rain west of the mountains. Saturday will be the coolest day 
with Max temps 10-15 degrees below average in the valleys, mountains 
and deserts. Skies will be mostly sunny in the deserts and in the 
mountains above the marine layer Friday and Saturday, with gusty 
westerly winds both days. 


Sunday through wednesday: the trough moves slowly inland Sunday with 
weak high pressure aloft bringing warmer days and a shallower marine 
layer Monday and Tuesday. But another trough Wednesday through 
Friday means that we will end may with gray and start out June with 
gloom. 


&& 


Aviation... 
232015z...coast/valleys/coastal mountain slopes...some clearing has 
occurred inland but much of the coastal areas and some inland areas 
remain covered with low clouds. Bases are currently scattered 1500-2000 
feet mean sea level and broken-overcast 2000-3500 ft mean sea level with tops to 4000 ft mean sea level. Low 
clouds will fill the coastal basin tonight after 03z, with similar 
bases and tops. Cigs 1000-2000 ft mean sea level are likely at times between 
06z and 15z Thursday. 


Mountain crests/Desert Mountain slopes/deserts...mostly clear skies 
with unrestricted vis through tonight. Some cumulus clouds have 
developed over the higher mountains. West winds gusting 25-35 mph 
through mountain passes late this afternoon and evening. 


&& 


Marine... 
no hazardous marine conditions are expected through Sunday. 
Occasional wind gusts 20-25 knots are possible over the outer waters 
during the afternoons and evenings Friday and Saturday. 


&& 


Beaches... 
a long-period south swell will continue to produce elevated surf and 
hazardous swimming conditions through Thursday, mainly in Orange and 
northern San Diego counties. Swells and surf will begin subsiding 
late Thursday. Check the surf zone forecast and the beach hazards 
statement for details. 
&& 


Skywarn... 
Skywarn activation will not be needed today. 


&& 


Sgx watches/warnings/advisories... 
California...beach hazards statement through Thursday afternoon for Orange 
County coastal areas-San Diego County coastal areas. 


Pz...none. 


&& 



National Weather Service Glossary of Abbreviations
Back to forecast page
Non-Expanded Version (with abbreviations)

Units: English | Metric

Find the Weather for any City, State or Zipcode, or Country:

U.S. State List | Severe Weather | Tropical Storms | Ski Conditions
United States | Canada | Central America | South America | Asia | Europe | Australia | Africa | Islands

Weather Underground

© Copyright 2018
The Weather Company, LLC