textproduct: San Diego

SYNOPSIS

Extensive low pressure over the western states will continue to deepen the marine layer and keep temperatures below average through this week. Morning low clouds over the coastal basin each day with a chance for a few fully overcast days at the beaches. Strong winds will continue for the deserts and desert slopes, peaking today and slowly weakening over the next several days.

..Updated Aviation/Marine Discussion

This morning...The marine layer remains about 3,500 ft deep with low clouds covering the coastal basin and extending to the top of the Cajon Pass in San Bernardino County and into the Borrego Desert near Jacumba in southeast San Diego County. Patchy drizzle will continue until about mid-morning west of the mountains.

An extensive low pressure system moving slowly inland to our north through Monday will be followed by a reinforcing shortwave trough on Tuesday. Low pressure will dominate the pattern over the western US. It will maintain cooler-than-normal conditions into next weekend, with a deep marine layer and widespread low clouds in the coastal basin during the nights and mornings. Temperatures will be around 5 to 10 degrees below average at the coast and 10 to 20 degrees below average for inland areas today. The low pressure system will continue to bring strong westerly winds in and below mtn passes on the desert slopes and adjacent desert areas. The winds peaked this evening with gusts 35-45 mph locally 65-70 mph through the San Gorgonio Pass. Winds will gradually weaken into early Monday. See the Wind Advisory for more details.

Models are in good agreement through Friday with with respect to the synoptic pattern before beginning to diverge next weekend as the trough is replaced over SoCal by high pressure building in from the southeast. Temperatures will gradually warm through the week but remain generally below normal, possibly rising to a few degrees above normal in the deserts next Sunday.

AVIATION

280900Z...Coast/Valleys/Foothills...Two layers of low clouds are covering the coastal basin: FEW-BKN with cigs 1500-2000 ft MSL and SCT-OVC with cigs 2500-3500 ft MSL.

Patchy -DZ/BR this morning in clouds with lower bases through the coastal basin lowering VIS to 4-6SM. VIS reductions also along mountain foothills where clouds meet terrain.

The lowest cigs mostly lift above 2500 ft MSL after 15z and clear the valleys 17-19Z Sun, with a 60% chance for only intermittent clearing along the immediate coast Sun afternoon. Clouds fill in at the coast and move inland after 01z Mon with bases 1500-2000 ft MSL, covering most of the lowlands by 05z and most of the Inland Empire by 09z Mon.

Mountains/Deserts...West winds remain elevated gusting 25-45 kt on the desert slopes into the deserts with local gusts to 65 kt through the San Gorgonio pass. MOD up/downdrafts in lee of mountains. Winds re-strengthen Sunday afternoon after 22z, gusting 25-45 kts along the desert slopes, 20-35 kts on the desert floor and up to 55 kts through the San Gorgonio Pass. Winds gradually weaken through the night 04-09z Mon.

MARINE

No hazardous marine conditions are expected through Friday.

SKYWARN

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

SGX WATCHES/WARNINGS/ADVISORIES

CA...Wind Advisory until 11 PM PDT this evening for San Diego County Deserts.

Wind Advisory until 2 AM PDT Monday for San Gorgonio Pass near Banning.

PZ...None.