18/627 PM.
A weak upper level trough will move over the area this weekend into Monday, cooling temperatures slightly and increasing marine layer stratus. A warming trend will begin Tuesday and peak on Thursday, with highs 5 to 10 degrees above normal.
(tdy-Mon), 18/107 PM.
Our quiet weather pattern will continue at least into early next week as a weak upper level low slowly moves through the state. High temperatures will cool 1-3 degrees and low clouds and fog will eventually return to coastal areas south of Pt Conception, possibly as early as Saturday in LA County. The upper low will bring some instability aloft but models are currently indicating minimal moisture. Still, can't rule out a chance (5-10%) of a shower or thunderstorm over the mountains Sunday/Monday.
(Tue-Fri), 18/129 PM.
The upper low is expected to weaken and move east Monday night leaving behind a weak baggy trough on Tuesday. Probably little noticeable change in weather conditions Tuesday except possibly a a degree or two of warming inland.
Beyond that, heights will be rising, though there is some uncertainty still how much as more than 50% of the current ensemble solutions maintain a weak trough over the eastern Pacific into next weekend. However, most of the ensembles also indicate warming 850 temps as high pressure tries to push into southern California from AZ. So a warming trend is the most likely outcome for the second half of next week, with a 20-30% chance of warmer valley areas reaching the high 90s or possibly 100 by Wednesday or Thursday. Then little change into next weekend.
19/0125z.
At 1700Z at KLAX, the marine layer was 1400 ft deep. The top of the inversion was at 4300 ft with a temperature of 19 C.
High confidence in VFR conds for KPRB, KPMD & KWJF.
Low to moderate confidence in the remaining sites. The timing of CIG and any VSBY restrictions may be off +/- 2 hrs and flight minimums by one category. There is a 40% chance of no low clouds for KSBP, KOXR and KSBA. For the LA Coastal sites, CIGs may be periodic or short term.
KLAX, Low to moderate confidence in the 00Z TAF. Return and dissipation of MVFR CIGs 015 (+/- 300 ft) tonight and Sat morning may differ by +/- 2 hrs from forecast times. The CIGs may be intermittent with a 30% chance that no restrictions occur. No significant east wind component expected.
KBUR, Moderate to high confidence in the 00Z TAF. There is a 20% chance of low clouds, most likely IFR if they occur. No wind issues expected.
18/117 PM.
For the outer waters, generally high confidence in the current forecast. Small Craft Advisory (SCA) level winds are likely across all the waters through Sunday afternoon, then for the waters west and south of Point Conception Sunday night through Monday night. There is a 40%-50% chance of SCA wind gusts again in these areas Tuesday night, otherwise conds will be below SCA levels Tuesday through Wednesday night. Expect steep, choppy seas with the SCA conditions.
For the inner waters N of Point Sal, generally high confidence in the current forecast. SCA wind gusts are likely during the afternoons and evenings through Sunday. Conds are then expected to be below SCA levels late Sunday night through Wednesday night, although there will still be a 20%-30% chance of occasional SCA level wind gusts at times each afternoon and evening.
For the inner waters S of Point Conception, moderate to high confidence in the current forecast. Conds are expected to be below SCA levels for the most part through Wednesday night. However, for the western Santa Barbara Channel, there is a 50% chance of SCA wind gusts Saturday afternoon/evening and again Monday afternoon/evening.
Ca, NONE. PZ, Small Craft Advisory in effect until 3 AM PDT Sunday for zones 645-676. (See LAXMWWLOX). Small Craft Advisory in effect until 5 PM PDT Sunday for zone 670. (See LAXMWWLOX). Small Craft Advisory in effect until 5 AM PDT Tuesday for zone 673. (See LAXMWWLOX).
