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Area Forecast Discussion (AFD)

Issued by San Diego, CA (SGX)

FXUS66 KSGX 260359

Area Forecast Discussion
National Weather Service San Diego CA
859 PM PDT Mon Mar 25 2019

The dry and mild through Tuesday, along with increasing high 
clouds as a low pressure trough moves inland to the north. Onshore
flow will increase Wednesday, bringing cooling and a small chance
of scattered, light showers. An approaching ridge will begin a 
warming trend on Friday, with further warming and drying through
the weekend as offshore flow develops.



UPDATE...Patchy low clouds have developed along the San Diego
County coast this evening and high clouds spreading in from the 
west. Expect any low clouds and fog to remain patchy and mostly
confined to central and southern San Diego County overnight. 


A weak ridge aloft will move east tonight as low pressure off the
PacNW coast drifts slowly east. Precipitation associated with the
storm system will spread SE across northern and central parts of 
the State through Wednesday, possibly reaching SoCal Wed night/Thu
morning. For now, any amounts look very light as onshore flow 
ramps up and the marine layer spreads clouds and fog back onto the
coastal mtn slopes.

The 12Z global model runs show fair agreement now in weakening the 
low as it slides inland beneath the strong west Canadian ridge this 
coming weekend. This in turn, has increased confidence in keeping
the weekend dry and mild with little impactful weather expected. 
The GFS keeps the weather dry early next week, but the ECMWF turns
wet. This is beyond the current forecast period so we will have 
some time to sort it out.

Slight cooling on Tuesday. Wednesday and Thursday will be the 
coolest days, along with gusty winds over the mts and deserts. 
Daytime temps should be about average by Friday, then back above 
by a few degrees over the weekend. A wind advisory may be needed 
at some point for the gusty onshore winds late Wed/Thu.


260230Z...Coast/Valleys...Scattered to broken high clouds through 
Tuesday. Pockets of intermittent low clouds at KSAN and KCRQ between 
07Z-16Z with bases near 1,500 feet.   

Mountains/Deserts...Scattered to broken high clouds through Tuesday. 


No hazardous marine weather through Tuesday. Isolated light showers 
are possible late Wednesday into Thursday morning as a trough 
passes by to the north. Gusty northwest winds of 15-25kt will follow 
the trough and may result in boating conditions hazardous for small 
craft Thursday afternoon and evening. 


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