14/1239 AM.
Warm but below normal temperatures will continue through Thursday, with expanding coastal morning low clouds. Temperatures are likely to increase towards the end of the week.
(Mon-Thu), 14/750 PM.
***UPDATE***
Added a slight chance for drizzle overnight into tomorrow morning across coastal sections roughly from the Oxnard plain south and east to the LA Basin. Drizzle will be possible anywhere that low clouds are forecasted, but this area has an increased chance for drizzle due to coastal eddy acting as a mesoscale lifting mechanism. I would not be surprised pockets of heavy drizzle or even a very light shower or two.
Winds could gusts up to 40 mph across Antelope foothills/southwest portion of valley Tuesday afternoon/early eve due to moderate onshore push (15% chance of wind advisory).
Otherwise, the forecast remains on track with some cooling each day into mid-week with no advisory level winds expected.
***From Previous Discussion***
Sunny skies prevailed this afternoon with generally light winds. Daytime highs so far today have generally been in the 70s to 80s with San Luis Obispo city of the hot spots today with temperatures in the mid to upper 80s.
Fairly benign conditions ahead of us. Temperatures will steadily lower a little each day through Wednesday with little change into Thursday. Why? For one, an upper level trough of low pressure over the western United States will amplify each day. Secondly, surface pressure gradients will keep coolish ocean air pushing inland while the north-to- south gradients from the weekend return to onshore. Lastly, the northwest winds over Santa Barbara County will decrease sharply over the next two days, which will allow the marine layer to flex more and expand. A strong coastal eddy is also still on track to form on Tuesday, which should really expand that cool marine layer air into the coastal valleys to lower mountain valleys and may bring some spots of pavement- wetting drizzle. As a result, highs will still generally be in the mid 70s to upper 80s which is far from cold, but not hot either and below normal by 5 or 10 degrees.
(Fri-Mon), 14/145 PM.
High pressure over the southeastern states will expand to the west Thursday through Saturday, but that expansion will battle a small yet potent closed low spinning north of southwest California. It seems like the vast majority of projections have settled on a pattern that will bring warming to the area, but the low will limit the high pressure expansion and the resulting warming. Some moderate northwest winds over Santa Barbara County, along with the higher pressure aloft will likely reduce the cooling effects of the marine layer. With all that in consideration, look for highs to bump up 5-ish degrees and settle in the 80s to lower 90s by Friday, which is right about normal for this time of the year. Heat Advisories or warnings look unlikely. The tropical storm train off western Mexico will remain active, but not seeing any significant moisture surge signals into California.
A weak likely moisture starved trough may approach the region Sunday or Monday, bringing increasing mid to high clouds and kick off a slow cooling trend with increased marine layer influence.
14/2327z.
At 2236Z at KLAX, the marine layer was 1500 feet deep. The top of the inversion was at 3200 feet with a temperature of 22 C.
High confidence in VFR TAF for desert airfields (KPMD & KWJF).
High confidence in organized marine layer south of Point Conception with MVFR conds at all sites. CIGs are expected to deepen with increasing southeast winds (6-12 kts), along with a decent chance for -DZ due to coastal eddy. Arrival times should be accurate within +/- 2 hours of current fcst, while clearing times +/- 3 hours.
KLAX, High confidence in TAF. Arrival times of MVFR CIGs 012 expected to arrive around 15/04Z (+/- 2 hours), deepening to near 2,000 ft threshold 15/10-15Z. Lower confidence on clearing, with a 30% chance CIGs persist or briefly clear than return through the forecast period. Southeast winds will likely reach or exceed 8 knots tonight into Tuesday morning, best chances 10Z-17Z.
KBUR, High confidence in TAF. Arrival of cigs likely between 05Z-08Z. Southeast winds up to 7 kt likely to continue all night into the morning before switching due south around noontime.
14/750 PM.
High confidence that Small Craft Advisory (SCA) winds and seas will continue through late tonight into early tomorrow morning over the Outer Waters. Seas over the outer waters are currently between 7 to 9 feet at short periods, 6 to 8 seconds, but will begin to subside as the winds ease. High confidence in relatively light winds with no SCA conditions over the area Tuesday through Thursday morning, with a return of normal Outer Waters (and potentially Santa Barbara Channel) northwest SCA winds for Thursday night into the weekend. These winds will generate a building short period swell over all waters.
Stronger than usual southeast winds are likely south of Point Conception tonight through mid to late morning on Tuesday. Winds will be strongest through the San Pedro Channel and northward into the eastern Santa Barbara Channel. While SCAs are not expected, local gusts 15-20 knots are possible between the islands. Locally choppy seas could make conditions hazardous for smaller craft.
Ca, NONE. PZ, Small Craft Advisory in effect until 9 AM PDT Tuesday for zones 670-673. (See LAXMWWLOX). Small Craft Advisory in effect until 3 AM PDT Tuesday for zone 676. (See LAXMWWLOX).
