17/114 PM.
Dry and warmer weather is expected into the weekend, though a cooling trend will begin Sunday as a low pressure system approaches. Rain chances will begin as early as Monday night along the Central Coast and Tuesday in Los Angeles.
(tdy-Mon), 17/148 PM.
Santa Ana winds peaked mid to late morning and have since dropped below advisory levels. Pressure gradients and upper support were both weaker than expected for this event, especially away from the mountain areas.
Meanwhile, temperatures definitely warmed with the offshore flow with highs mostly in the 70s across coast and valleys and a few lower 80s across inland Ventura County.
Additional warming is expected in all areas Saturday with lingering offshore flow and the departure of the cold air advection that limited interior warming today. Most inland areas should warm up at least 5 degrees over today, possibly as much as 10 degrees. Coastal areas got most of their warming today but should warm a few more degrees Saturday. Some lingering offshore winds are likely Saturday morning, mainly mountains and valleys, but below advisory levels.
A cooling trend will begin Sunday and continue Monday as a cold and cutoff upper low slowly meanders down the coast. Increasing morning stratus is possible near the coast Monday with increasing onshore flow ahead of the upper low. Most of the ensemble solutions keep rain north of SLO County at least through Monday evening.
(Tue-Fri), 17/206 PM.
Still lots of uncertainty with the details of the incoming cutoff low. Rain chances remain quite high, 70-80% north and 40-60% south, but timing and amounts are still very much in question. The best chance of rain is Tuesday, but could be as early as late Monday along the Central Coast, and rain chances could linger as late as Wednesday night. The hangup in the forecast hinges on the speed of the approaching low and how far south it ultimately drops. With cutoff lows this this is a very difficult task 3-4 days out. While most of the ensemble solutions keep rain amounts south of Pt Conception under a half inch and under and inch in the north, there are some solutions for the Central Coast as high as 2 inches. That would likely require the low to drop much farther than most of the ensembles are suggesting creating a colder and more unstable air mass aloft that could generate heavier showers and possible thunderstorms. It's likely that confidence in this forecast will remain very low through the weekend.
17/1243z.
At 06Z at KLAX, there was no marine layer nor an inversion.
Moderate confidence in TAFs, except high confidence in KPRB, KSMX, and KSBP.
Timing of wind changes may be off +/- 2 hours, with N-NE gusts off by +/- 5kt at any point through the morning. Lgt to moderate LLWS & turbulence is possible over and near mountainous terrain through 00Z Sat, especially across Los Angeles and Ventura counties.
There is a 40% chance of very brief MVFR cigs at KSMO, KLAX, KLGB, KBUR, and KVNY and at some point through 17Z Fri, however, conds may scatter and reform frequently due to the patchy nature of the marine layer clouds.
KLAX, Moderate confidence in TAF. There is a 40% chance of very brief BKN012-022 cigs through 17Z Fri, and conds may scatter and reform frequently. There is a 60% chance of east wind component reaching 7-8kts until 17Z, with a 30% chance of reaching 10 kts.
KBUR, Moderate confidence in TAF. Wind changes may be off by +/- 2 hours, with a 20% of no northerly winds through the period.
17/713 AM.
For the Outer Waters, moderate to high confidence in current forecast. A combination of Small Craft Advisory (SCA) level winds and seas are expected through this morning, with a 30% chance of lingering through tonight. Except for far northern outer waters (PZZ670) which the Small Craft Advisory has been extended through late tonight. Saturday through Monday afternoon, there is a 20-30% chance of SCA level winds. An approaching cold front may bring SCA level southerly winds, along with a chance for showers between Monday evening and Tuesday morning.
For the Inner Waters north of Point Sal, moderate to high confidence in current forecast. Seas may flirt with SCA levels through mid- morning across the western portion of the zone, but are forecast to drop below advisory levels through the morning. From late this morning through Monday, high confidence in winds and seas remaining below SCA levels. An approaching cold front may bring SCA level southerly winds, along with a chance for showers between Monday evening and Tuesday morning.
For the Inner Waters south of Point Conception, moderate to high confidence in current forecast. SCA level NE winds will develop early this morning from Ventura south to Santa Monica and spread out towards Anacapa Island. From Point Mugu to Malibu this morning, there is low chance for Gale Force wind gusts nearshore below any canyons/passes. Saturday through Monday, high confidence in winds and seas remaining below SCA criteria for all southern Inner Waters.
Ca, NONE. PZ, NONE.
