17/740 PM.
Slight warming and a shrinking marine layer are expected Friday into the weekend. Temperatures will cool by a few degrees Sunday and Monday, then another gradual warming trend is likely through at least the middle of next week.
(Thu-Sun), 17/808 PM.
***UPDATE***
Yet another mostly sunny day in the books, with high temperatures in the 70s and 80s - about 5 to 10 degrees below normal for this time of year. Typical breezy, sub-advisory, onshore afternoon winds pushed across most of the region today, highest across the Antelope Valley Foothills, and north-northwest sub-advisory Sundowner winds are occuring across southwestern Santa Barbara County. Current Satellite imagery shows very limited Marine Layer Clouds, with clouds really only located west and southwest of Catalina Island. This does potentially put a wrinkle in the overnight through morning sky forecast, with clouds slow to arrive along the coasts. With the decrease in onshore flow from the north and lack of a strong eddy, clouds are expected to remain out of the valleys, and may struggle to reach the coasts south of Point Conception as well.
Quicker clearing (if clouds do reach the coast), and a few degrees of warming, with highs still in the 70s and 80s, is still forecast for tomorrow.
Besides the sky coverage, no updates were needed for the evening forecast update.
***From Previous Discussion***
Not much to say about the local weather conditions for at least the next week or so. An upper level low over northern California will move slowly east resulting in a minor warming trend Friday and Saturday, then little change Sunday, though high temperatures will still just be within a few degrees of normal either way. Pressure gradients in all directions will remain light so no significant winds expected the next few days. There's a good chance that marine layer cloud coverage south of Pt Conception will be much less starting Friday, though still expecting morning stratus along the Central Coast through the weekend.
(Mon-Thu), 17/150 PM.
Another little trough moves in late Sunday into Monday for a slight cooling trend but probably not that noticeable. The only potential impact will be the likely return of the marine layer to southern areas and 1-3 degrees of cooling area-wide.
The pendulum will swing back towards warming by the middle of next week but again nothing dramatic in terms of temperatures. Highs in the warmer valleys will return to the lower 90s, which is basically near normal for this time of year, while Downtown LA and other inland coastal areas get back into the low to mid 80s, which again is close to normal. Most of the ensembles indicate fairly light gradients next week, except mid to late week where there is 40-50% chance of weak to moderate Sundowners in the Santa Barbara area.
18/0252z.
At 1716Z at KLAX, the marine layer was 2000 feet deep. The top of the inversion was at 4900 feet with a temperature of 17 C.
High confidence in TAFs for KPMD and KWJF.
Low to moderate confidence in remaining sites. Moderate confidence in the Central Coast and LA Coastal sites, and low confidence in KSBA, KOXR, KBUR and KVNY where there is a 20-30 percent chance of low CIGs overnight, mostly likely MVFR if they occur. 10% chance of LIFR conds at KPRB/KSBP/KSMX late tonight.
KLAX, Moderate confidence in the 00Z TAF. Return of MVFR cigs tonight likely between 08Z to 12Z. Good confidence that any east wind component tonight will remain below 8 kt.
KBUR, Low to moderate confidence in the 00Z TAF. 20-30% chance of MVFR CIGs between 10Z-16Z Fri.
17/822 PM.
Moderate confidence in fairly typical Small Craft Advisory (SCA) northwest winds across the outer waters south and southwest of Point Sal, then higher confidence in more widespread SCA winds Friday afternoon through Sunday across the outer waters and nearshore waters along the Central Coast. Choppy, short period seas will develop.
Across the Santa Barbara Channel, there is a 30-40% chance of SCA winds Friday afternoon and evening, then a 40-60% chance Saturday and Sunday in the afternoon/evening hours. Local gusts near 20 knot will be common each afternoon and evening through the San Pedro Channel and Santa Monica Bay.
Ca, NONE. PZ, Small Craft Advisory in effect from 3 PM to 9 PM PDT Friday for zone 645. (See LAXMWWLOX). Small Craft Advisory in effect from 3 PM Friday to 3 AM PDT Sunday for zone 670. (See LAXMWWLOX). Small Craft Advisory in effect until 3 AM PDT Sunday for zones 673-676. (See LAXMWWLOX).
