Marine Weather and Tide Forecast for Rossmoor, CA

.SHORT TERM (TDY-THU)...04/233 AM.

A 597 dam upper high will sit over AZ through the short term with 594-595 dam hgts over Srn CA. There will be mdt-stg onshore flow to the east and weak-mdt onshore flow to the north. The marine layer will be near 1000 ft and night through morning low clouds and fog will affect the csts each day. Some nearshore areas will see slow clearing in the afternoon due to the strong onshore to the east. The Central Coast may also see some dense fog around sunrise.

Max temps will be pretty close to normal across the csts and vlys.
Since it is August "close to normal" in the vlys still means 90 to 101 degrees and mid to upper 80s in the inland cstl sections. The lower mtn elevations and far interior sections will not feel the effects of the onshore flow and max temps will range from 100 to 109 degrees or 5 to 10 degrees above normal. Heat warnings continue for Antelope Valley, Cuyama Valley, and northern Ventura mountains - please see LAXNPWLOX for details.

.LONG TERM (FRI-MON)...04/233 AM.

The upper high moves to the west on Friday and hgts bump up to 596 dam and remain there through Saturday. At the same time there is a monsoon push and PWs rise to about 1.25 inches. Max temps will only rise a degree or two, but the increased humidity will increase the heat risk as well as keeping the overnight lows well above normal. The combination of well above normal highs and lows as well as increased humidities will bring heat danger to the far interior and lower mtn elevations. As a result the heat warnings for these areas have been xtnd through Saturday evening. As the weekend approaches a suite of heat advisories will likely be issued for many vly areas. The coastal areas will not be as warm as the rest of the area due to the onshore flow and marine layer.

The onshore flow will continue and this will keep the night through morning low clouds going through the period. The very high hgts will keep the marine layer under a 1000 ft and the vlys will remain clear.

At this time there is no convection in the fcst despite the increase in monsoon moisture, but this will need watching as the week progresses.

Starting Sunday and continuing into Monday the upper high will weaken and the onshore flow will increase to almost 10 mb onshore to the east. Max temps are forecast to cool 1-2 degrees Sunday and 2 to 4 more degrees on Monday.

AVIATION
04/0933Z.

At 0832Z at KLAX, the marine layer was 1100 feet deep. The top of the inversion was near 2100 feet with a temp of 27 C.

High confidence in VFR conds for KPRB, KBUR, KVNY, KPMD and KWJF.
There is a 10% chance for brief LIFR conds at KPRB/KBUR/KVNY between 12Z and 15Z.

Moderate confidence with the remaining TAFs. VFR transition could be up to 90 minutes later than fcst. Cig hgts may be off by +/- 200 ft.

KLAX...Moderate confidence in TAF. VFR conds could arrive as late as 1930Z. No significant east wind component expected.

KBUR...High confidence in TAF. However there is a 10% chance for BKN005 conds 12Z-15Z.

MARINE
04/234 AM.

Winds and seas are expected to remain below Small Craft Advisory (SCA) criteria through the week, with the exception of northwest winds locally gusting to 20-25 knots in typically windy areas near Point Conception each afternoon and evening.

Dense fog may affect portions of the coastal waters each night through morning through much of the week, especially across the waters north and west of Point Conception.

LOX WATCHES/WARNINGS/ADVISORIES
CA...Extreme Heat Warning in effect until 8 PM PDT Saturday for zones 38-377-381>383. (See LAXNPWLOX).
Heat Advisory in effect until 8 PM PDT Saturday for zones 344-345-353-375-376-378>380. (See LAXNPWLOX).
PZ...NONE.