Marine Weather and Tide Forecast for South Monrovia Island, CA

.SHORT TERM (TDY-MON)...18/148 PM.

Clouds are very slowly clearing across the region today as the air mass recovers from few days of deep marine layer and strong onshore flow. Warmer air aloft is moving into the area today but clouds are proving stubborn south of Pt Conception as weak cyclonic flow is trapping moisture in the boundary layer below the lee side of the Transverse range. As the marine inversion continues to shrink and drier air aloft descends and punches through the inversion this afternoon and evening clouds will dissipate rapidly leading to mostly clear skies tonight into Saturday.

Chamber of commerce weather is expected over the weekend into Monday with plenty of sunshine and temperatures rising to within a few degrees of normal. Low confidence on when or if low clouds and fog will reform but clouds should just be morning feature at most. Gradients are already trending weaker today and expect that to really kick in tonight into early Saturday with a 4-5mb offshore trend, leading to some areas of breezy northeast winds across the LA Mountains and some of the higher valley areas Saturday morning.

.LONG TERM (TUE-FRI)...18/158 PM.

Onshore flow begins its return as early as Sunday but especially Monday as the next trough deepens along the West Coast. No precipitation expected locally but temperatures will begin a slow cooling trend that will continue through the week. Low clouds and fog will return to coastal areas by Monday if not before and eventually the valleys as cooling aloft deepens the marine inversion. The increasing onshore flow will create increasing west to southwest winds especially in the Antelope Valley. But otherwise a fairly low impact period of weather with another long stretch of below normal temperatures. Longer range models indicate a continued cool pattern through next week and even into the last week of April.

AVIATION
18/1731Z.

At 1658Z at KLAX, there was a 6900 ft deep moist layer with multiple cloud decks.

High confidence in TAFs for KPMD and KWJF.

Moderate confidence in remaining TAFs through this afternoon as flight cats will continuously bounce between MVFR and VFR. Lower confidence after 02Z. Moderate confidence in cigs at coastal sites late tonight into tomorrow morning, but low confidence in timing and minimum flight cats. Flight cat changes may be off +/- 4 hours and minimum flight cats may be off by at least one cat. There is a 30-50% chance for VFR conds to prevail tonight through tomorrow morning at KOXR, KCMA, KSMO, KLAX, and KLGB, with highest chances at KCMA. There is a 20% chance for IFR to MVFR conds at KBUR and KVNY between 06Z and 15Z.

KLAX...Moderate confidence in 18Z TAF. Conds will likely bounce between MVFR to VFR through 22Z. There is a 20% chance for VFR cons to prevail thereafter through the period. Otherwise, flight cat changes may be off +/- 4 hours. Low confidence in minimum flight cat. There is a low (10% chance) for cigs 005-010 once they arrive tonight. No significant east wind component expected.

KBUR...Overall, moderate confidence in 18Z TAF. Conds will likely bounce between MVFR to VFR through 22Z. There is a 20% chance for IFR to MVFR conds between 06Z and 15Z.

MARINE
18/141 PM.

For the Outer Waters, moderate to high confidence in current forecast. There is a 30% chance for localized Small Craft Advisory (SCA) level northwest wind gusts around Point Conception down to the Northern Channel Islands and in the northern Outer Waters this afternoon through early evening hours. Saturday through Monday morning, there is a 20-30% chance for such winds around Point Conception and the Channel Islands in the afternoon and evening. Elsewhere, winds and seas are expected to remain sub advisory through Monday morning. Then, Monday afternoon into at least Tuesday, there is a 60-80% chance of SCA level winds.

For the Inner Waters north of Point Sal, moderate to high confidence in current forecast. There is a 30% chance for localized SCA level wind gusts this afternoon into the evening near Pismo Beach. Saturday through Monday morning, high confidence in winds and seas remaining below SCA levels. From Monday afternoon through at least Tuesday, there is a 30-40% chance of SCA level winds in the afternoon and evening hours.

For the Inner Waters south of Point Conception, moderate to high confidence in current forecast. Today through Tuesday, high confidence in winds and seas remaining below SCA levels across most areas. The only exception will be the western half of the Santa Barbara Channel where there is a 30-50% of SCA level wind gusts in the afternoon through evening hours.

LOX WATCHES/WARNINGS/ADVISORIES
CA...NONE.
PZ...NONE.