Marine Weather and Tide Forecast for Hermosa Beach, CA

.SHORT TERM (TDY-SUN)...15/1054 PM.

***UPDATE***

The Santa Ana winds are well established over the area this evening, with offshore LAX-DAG gradient of 5.5 mb, and offshore LAX-BFL gradient of 4.6 mb, twice as strong as the gradients were 24 hours ago. Peak gusts reached 60-80 mph today, with the strongest winds occuring in the mountains of Ventura and Los Angeles Counties. Expecting Santa Ana winds to shift further east and strengthen more overnight and into Friday morning. No significant changes in terms of the forecast for the winds, still thinking there is potential for mountain areas to see gusts up to 90 mph and stronger gusts up to 60 mph for the LA valleys, and Ventura valleys and coasts. One high resolution solution indicates significant more widespread downsloped winds developing southwest of the San Gabriel, Santa Susana and Santa Monica mountains after midnight until around 5AM. Peak winds shift to favor the Santa Susana Mountains and Ventura County after 5AM.
Gusts during these times could exceed 60 mph at times.

Temperatures were quite warm today, especially near the coasts where a few areas pushed the upper 90s. Friday, temperatures were warmed more for portions of Santa Barbara County and southern Ventura County, as the gradients should remain strongly offshore.
Expecting more widespread 90s near the coasts, and isolated 100s.
Offshore winds weaken Saturday and Sunday, leading to a cooling trend.

***From Previous Discussion***

Santa Ana winds arrived on schedule and with more aggressive speeds than expected. Some areas in the San Gabriel Mountains have already reported 70+ mph wind gusts today and models are still indicating additional upper level support Friday morning as well as offshore gradients from the east peaking between 8 and 9mb. So just making some minor tweaks for Friday based on today's conditions. Temperatures have been warmed a few degrees, especially at the coast where temps will be the warmest, even more so than the valleys. And based on today's wind speeds there's at least a 30-40% chance of wind gusts in the LA County mountains reaching 90mph and similar chances for valleys and Ventura county coastal areas to see wind gusts as high as 60 mph. Since even 1mb of offset in the gradients can result in 5 or more degrees offset in the temperatures, confidence in the exact highs is on the lower side but should be in the ball park.

Also, overnight lows will, in general, be quite warm tonight across the coast and valleys. Some areas that stay windy all night may not drop below 75 and wouldn't be surprised if some areas stay above 80 all night.

On Saturday, upper level support and surface gradients weaken but still expecting a windy day, albeit probably 15-30 mph weaker than Friday. And with the offshore flow and cold advection weakening as well temperatures at the coast should cool at least a few degrees while valleys and other interior areas either remain the same or warm slightly.

For Sunday, all areas except the mountains and deserts will cool at least 3-6 degrees. Interior areas will warm as cold advection continues to weaken.

.LONG TERM (MON-THU)...15/230 PM.

More cooling is in store on Monday as an upper low moves down the coast. Hgts will fall from 580 dam Sunday afternoon to 576 dam Monday afternoon. Actual onshore flow will develop and will increase through the day. Some morning marine layer clouds may even develop over the Central Coast. Max temps will fall 4 to 8 degrees. This will bring max temps down to near normals.

There is increasing confidence in rain chances next week, though timing is still quite uncertain as are the amounts. Virtually all the solutions from the ENS and GEFS ensembles indicate at least some light rain, most likely starting Wednesday, but could start as early as Tuesday afternoon or as late as Wednesday evening. Rain amounts are even more scattered but mostly around a half inch area-wide. It's a tricky pattern with the upper low dropping south along the California coast and a lot of uncertainnesshow far offshore and where it will turn inland.
Might take another few days to have more confidence in amounts and timing. There are more than a few solutions that bring an inch or more so this needs to be followed closely, especially with the possibility of brush fires during the current strong Santa Ana winds.

AVIATION
16/0822Z.

At 06Z at KLAX, there was no marine layer or inversion.

High confidence in CAVU conditions for all sites through the period. Moderate confidence in direction/strength of northeast- east winds, gusts may be off by 020-030 degrees and 10-15 knots respectively.

KLAX...High confidence in 06Z in CAVU conditions through the period. Moderate confidence in winds, and there is the potential for an extended period of gusty easterly winds from about 17Z to 22Z, with gusts up to 25 kt.

KBUR...High confidence in CAVU conditions through the TAF period.
Moderate confidence in winds as timing may be off by 2-3 hours and strength could be +/- 10 knots.

MARINE
16/122 AM.

For the Outer Waters, moderate to high confidence in current forecast. Through Sunday, high confidence in winds and seas remaining below Small Craft Advisory (SCA) levels across PZZ670/673. For PZZ676, there is a 60-80% chance of SCA level winds today. On Monday and Tuesday, there is a 50-60% chance of SCA level winds across all of the Outer Waters with seas hovering around SCA levels.

For the Inner Waters north of Point Sal, moderate to high confidence in current forecast. There is a 40-50% chance of SCA level northeast winds this morning. For Saturday and Sunday, high confidence in winds and seas remaining below SCA levels. On Monday and Tuesday, there is a 50% chance of SCA level winds, mainly in the afternoon and evening hours with seas hovering near SCA levels.

For the Inner Waters south of Point Conception, moderate to high confidence in current forecast. There is a 60-70% chance of GALE force winds from Ventura to Santa Monica with a 40-60% chance of SCA level winds elsewhere (especially across the San Pedro Channel). For tonight and Saturday, there is a 50% chance of SCA level northeast winds from Point Mugu to Santa Monica with high confidence in winds and seas remaining below SCA levels elsewhere.
For Sunday through Tuesday, high confidence in winds and seas remaining below SCA levels for most areas except for the western half of the Santa Barbara Channel where there is a 50-60% chance of SCA level winds.

LOX WATCHES/WARNINGS/ADVISORIES
CA...Wind Advisory in effect until 8 PM PDT this evening for zones 88-354-355-358-362-370>374-376-377. (See LAXNPWLOX).
Heat Advisory in effect until 8 PM PDT Saturday for zones 340-341-346-347-349-350-354-355-362-366>368. (See LAXNPWLOX).
High Wind Warning in effect until 8 PM PDT this evening for zones 369-375-378>380. (See LAXNPWLOX).
Red Flag Warning in effect until 8 PM PDT Saturday for zones 288-354>358-362-369>382-548. (See LAXRFWLOX).
Red Flag Warning in effect until 6 PM PDT this evening for zones 342-345-353. (See LAXRFWLOX).
PZ...Small Craft Advisory in effect until 3 AM PDT early this morning for zones 650-655. (See LAXMWWLOX).
Gale Warning in effect until 5 PM PDT this afternoon for zones 650-655. (See LAXMWWLOX).
Small Craft Advisory in effect until 5 PM PDT this afternoon for zone 676. (See LAXMWWLOX).