Marine Weather and Tide Forecast for Santa Monica, CA

.SHORT TERM (TDY-FRI)...18/938 AM.

***UPDATE***

No changes with the morning update. Heat is the main concern today away from the coast with moderate risk of heat illness for those with prolonged exposure or vulnerable people such as the elderly and young.

The focus of today will be examining and messaging the upcoming fairly widespread wind expected to peak Friday into Saturday with isolated, power outages, downed trees, and elevated fire weather the main impacts.

***From Previous Discussion***

Another warm day on tap for today, as high pressure aloft peaks and the already weak onshore flow persists. While coastal and valley areas will see similar temperatures as yesterday, interior valleys and mountains will bump up 3-8 degrees as highs of 95-105 become common (10-15 degrees above normal). While Heat Advisories are not anticipated, there are pockets where the case could be made (like the Santa Clarita Valley, Salinas Valley, and some lower mountains like the Santa Monicas) as highs around 100 degrees are expected with lows around 70. As such, there will be an elevated risk of heat illnesses for anyone active outdoors during the heat of the day for those areas (much cooler conditions are just a day or two away). The gusty northwest winds from the last few days are finally weakening, and we will get a brief break today. Some low clouds and likely dense fog are trying to form along the Central Coast and the Los Angeles Coasts, but unsure how much we will end up seeing.

A shortwave trough will slowly move through the area later Thursday through Saturday. This will do a few things. First of all, this will tighten the north-to-south pressure gradients while descending some wind energy aloft closer to the surface. This adds up to another round of moderate to locally strong northwest to north winds. Expecting wind gusts of 30 to 50 mph to be common over the typically wind prone areas, with a moderate risk of isolated gusts to 60 mph over southern Santa Barbara County, the I-5 Corridor, and the Antelope Valley. Winds this strong can cause power outages and downed trees, as well as blowing dust in the deserts. Secondly, this should help the marine layer to reestablish itself, except for some of Ventura County and southern Santa Barbara County thanks to the drying affect of the aforementioned northwest winds. Lastly, the cooler airmass will allow temperatures to trend down a little on Thursday, then much more noticeably on Friday - with temperatures at or below normal to follow through at least early next week.

.LONG TERM (SAT-TUE)...18/251 AM.

The moderate to locally strong northwest to north winds will continue and peak in some areas Saturday Night, then gradually weak Sunday into Monday. At the same time, heights aloft lower further while onshore flow strengthens. South-to-north pressure gradients also strengthen (with some projections showing LAX-BFL at +6.0 millibars Monday and Tuesday) which is usually a good indicator for poor afternoon clearing. As such, expect cool conditions for the first half of next week with a few spits of drizzle possible along the coast. Gusty onshore flow also looks favorable for the typical interior spots.

AVIATION
18/1745Z.

At 1657Z at KLAX, the marine layer was 1500 feet deep. The top of the inversion was 5700 feet with a maximum temperature of 25 C.

High confidence in TAFs for KPRB, KPMD, and KWJF.

Moderate confidence in TAFs for KBUR and KVNY. There is a 20% chance for IFR to MVFR between 09Z and 17Z.

Low confidence in remaining TAFs. There is a 10-40% chance for VFR conds to prevail at any coastal site, but highest chances are for KSBA and KCMA. Otherwise, flight cat change time may be off by 3 hours, and minimum flight cat may be off by 1 cat.

KLAX...Low confidence in TAF after 06Z due to uncertainty in marine layer clouds. There is a 15% chance for VFR conds to prevail through the period. Otherwise, arrival of marine layer clouds may be as early as 05Z or as late at 11Z. There is a 40% chance for cigs to be as low of 005-009 once cigs are present.
Any east wind component is expected to be less than 6 knots.

KBUR...Moderate confidence in TAF. There is a 20% chance for cigs 005-012 between 09Z and 17Z. However, if cigs arrive, there is a 10% chance for cigs 002-004.

MARINE
18/847 AM.

High confidence in Small Craft Advisory (SCA) to Gale Force northwest winds across the Outer Waters and Inner Waters along the Central coast through the weekend. The period with the strongest winds is likely to be Friday afternoon through Saturday night. For the next several days seas will hover around 10 feet for the outers waters, increasing to up to 14 feet late this week.

Across the Santa Barbara Channel, after a lull in the winds today, a return of SCA level winds is likely Thursday through the weekend. Gale force gusts are possible in the western portion of the zone Thursday evening and again Friday and Saturday, with winds potentially impacting immediate coastlines during this period. Highest chance of significant winds impacting the coastlines is Friday through Saturday in the afternoon through late night hours.

For the Inner Waters off the Los Angeles and Orange County coasts lower confidence in forecast for Thursday into the weekend as winds could increase to SCA levels, but are favored to be confined to the western portion of the zone away from the immediate coasts.

LOX WATCHES/WARNINGS/ADVISORIES
CA...NONE.
PZ...Small Craft Advisory in effect until 3 PM PDT Thursday for zones 645-673-676. (See LAXMWWLOX).
Gale Watch in effect from Thursday afternoon through late Thursday night for zone 645. (See LAXMWWLOX).
Small Craft Advisory in effect from 3 PM to 6 PM PDT Thursday for zone 650. (See LAXMWWLOX).
Gale Watch in effect Thursday evening for zone 650. (See LAXMWWLOX).
Small Craft Advisory in effect until 3 PM PDT this afternoon for zone 670. (See LAXMWWLOX).
Gale Warning in effect from 3 PM this afternoon to 3 AM PDT Sunday for zone 670. (See LAXMWWLOX).
Gale Warning in effect from 3 PM Thursday to 3 AM PDT Sunday for zones 673-676. (See LAXMWWLOX).