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Area Forecast Discussion (AFD)

Issued by San Diego, CA (SGX)

FXUS66 KSGX 242027

Area Forecast Discussion
National Weather Service San Diego CA
126 PM PDT Sun Mar 24 2019

Warming will continue through Monday under fair skies. High clouds 
will begin to thicken on Tuesday ahead of another Pacific storm that 
will move inland across the State midweek. It will bring breezy and 
cooler conditions, and a chance of scattered, light showers late
Wednesday. The weather looks dry for next weekend with some warming 



A few patches of clouds lingered early this afternoon, but most areas 
are clear. Surface pressure gradients were weak at 1 PM PDT with 
mostly light winds reported.  

A very weak ridge was moving over SoCal today, helping to keep the 
weather fair and allowing some warming under strong Spring sunshine. 
Only patchy low clouds/fog are expected to materialize overnight, 
but most areas should stay clear, allowing temperatures to drop 
through the 50s and into the 40s in many areas west of the mountains 
by morning. For Monday, modest height and thickness rises will 
continue the daytime warming trend under fair skies. 

By Tuesday, low clouds may be more widespread along the Coast with 
again, some patchy fog, otherwise, high clouds will thicken through 
the day ahead of a large EastPac storm system that will move across 
the State Wednesday and Thursday. The bulk of the precip will remain 
to the north of SoCal, but we have low POPS in the forecast for the 
chance of some scattered, light showers, with the best chance on 
Wednesday night.

The global operational models (CMC/GFS/ECMWF) continue to  handle 
the subsequent pattern across the West into next weekend quite 
differently. The GFS digs additional energy sharply, while the 
ECMWF does not, allowing heights to rise over the SW for much 
warmer weather. The CMC also shows more digging, but farther 
east. The GFS also suggests moderate (cool) Santa Ana winds are 
possible on Sunday, but due to the pattern uncertainty, that has 
been left out of the picture. For now, we have used a blend of temp 
guidance for next weekend. All models keep the weather dry for this 


232000Z...Coast/Valleys...SCT low clouds with bases around 2500 ft 
MSL and tops to 5000 ft MSL will persist this afternoon but vis 
should remain unrestricted. CLR-SCT conditions will prevail 
overnight, except near the immediate coast where patches of low 
clouds and fog could impact coastal TAF locations with cigs at or 
blo 1000 ft MSL and vis 3-5 miles between 09Z and 15Z Monday. 
However, confidence is only moderate.

Mountains/Deserts...Mostly clear skies with unrestricted vis will 
prevail through tonight.


A long-period swell will continue to bring combined seas of 8-9 ft 
in the outer waters, subsiding this afternoon. Otherwise, no 
hazardous marine weather is expected through Thursday.


A west-northwest swell of 6-8 ft from 290 degrees with a 15-17 
second period will generate high surf today with sets to 8 ft 
possible, mainly in southern San Diego County. A High Surf Advisory 
is in effect for Orange and San Diego Counties until 9 PM tonight. 


Skywarn activation is not requested. However weather spotters are
encouraged to report significant weather conditions.


CA...High Surf Advisory until 9 PM PDT this evening for Orange County 
     Coastal Areas-San Diego County Coastal Areas.