Marine Weather and Tide Forecast for Channel Islands Beach, CA

.SHORT TERM (TDY-WED)...17/245 AM.

Over the next three days a very large and hot upper high, currently centered over TX, will shift to the west and end up over AZ. Hgts will no change much and will sit near 594 dam through the period. The sfc gradients will not exhibit much change either. The N/S gradient will be near neutral in the morning and weakly onshore in the afternoon. The W/E gradient will be weakly onshore in the morning and moderately onshore in the afternoons.

Marine layer clouds will be confined to the coastal sections. Good confidence that the Central Coast will have the low clouds each morning. Less confidence for the csts south of Pt Conception where beaches could be clear on any given morning.

The high pressure, hier than normal hgts and weaker than normal onshore flow will bring another round of heat to Srn CA. Most areas will see 2 to 4 degrees of warming today although some vly areas will see up to 6 degrees. This warming will bring warmer than normal temps to all areas save for the Central Coast which will end up 2 or 3 degrees blo normal. Another 2 to 4 degrees of warming (locally 6 degrees across the Central Coast) Tuesday will bring above normal max temps to all areas. Most areas will see 1 or 2 degrees of additional warming on Wednesday. The strong inversion, much warmer than normal sea sfc temps and the warm atmosphere will also bring warmer than normal overnight low temps to much of the area. Most cst/vly locations will only have lows in the upper 60s to lower 70s.

The combination of warmer than normal highs and lows will bring significant heat risk to many areas. HEat advisories were issued Sunday for the San Fernando, San Gabriel, and Santa Clarita Valleys as well as the lower mtn elevations. There is a 40 percent chance the downtown LA area, the VTA county vlys, and the Santa Monica mtns will also need heat advisories starting Wednesday. Please see the product LAXNPWLOX for all of the details.

Gusty north winds will affect southwest Santa Barbara County and the I-5 corridor near the Grapevine each evening and overnight.
While most of these winds are expected to remain below advisory levels, there is a chance for advisory level winds in the Gaviota to San Marcos Pass area.

.LONG TERM (THU-SUN)...17/245 AM.

Thursday will greatly resemble Wednesday as there will be little change in any of the synoptic parameters. The only change will be some cooling across the Central Coast as that area will have a stronger sea breeze.

There will be a little bit of cooling on Friday mostly due to an increase in mid and high level clouds. Still max temps will remain well above normal. The upper high is forecast to migrate to the four corners area which will set up SE monsoon flow over Srn CA.
PWs approach 1.5" across Srn LA county. This influx of moisture will allow for a non zero chc of showers or TSTMs to develop over the mtns and Antelope Vly.

The upper high will be nudged to the east for the weekend as a weak trof moves through the PACNW and the northern half of the state. The weak lift from the trof may bring a little better low cloud development although this is far from certain. Look for 1 to 2 degrees of cooling each day - maybe a little more for SLO county due to the proximity to the trof. The cooling will bring most areas north of Pt Conception down to near or below normal temps.
South of Pt Conception, however, most max temps will remain a few degrees above normal.

AVIATION
17/0945Z.

At 0832Z at KLAX, the marine layer was at 900 feet deep. The top of the inversion was near 1800 feet with a temperature of 26 C.

High confidence in VFR TAFs for KBUR, KVNY, KPMD & KWJF.

Low to moderate confidence in remaining TAFs. VFR timing may be off +/- 90 minutes. Cig hgt may be off by +/- 200 ft. There is a 20 percent chc of no cigs at any site south of Pt Conception.

KLAX...Moderate confidence in TAF. There is a 30 percent chc of OVC008 conds. No significant east wind component expected.

KBUR...High confidence in VFR TAF.

MARINE
17/250 AM.

Moderate to high confidence in forecast. Current Small Craft Advisory (SCA) for gusty winds over the outer waters from near Point Conception southward to San Nicolas Island and in the vicinity of the Channel Islands is on track. Good chance for SCA winds to be ongoing from through much of the week over all of the outer waters starting this evening. Nearshore along the Central Coast, afternoon through evening SCA winds are likely Tuesday through Friday.

For the inner waters, SCA winds will affect the western SBA Channel this afternoon and tonight. This pattern will continue, with SCA winds in the afternoon and overnight period, decreasing into the morning hours each day. For PZZ655, SCA winds are not expected, although local gusts to 25 knots are likely nearshore in the afternoon and evening hours through Wednesday.

Building short period seas are expected over the next several days, likely rising to around 7-9 feet over the outer waters.

LOX WATCHES/WARNINGS/ADVISORIES
CA...Heat Advisory in effect from 10 AM Tuesday to 8 PM PDT Thursday for zones 38-88-343>345-351-353-371>373-375-376-379-380-548. (See LAXNPWLOX).
PZ...Small Craft Advisory in effect until 3 AM PDT Tuesday for zone 650. (See LAXMWWLOX).
Small Craft Advisory in effect until 3 AM PDT Wednesday for zones 673-676. (See LAXMWWLOX).