Area Forecast Discussion

SYNOPSIS

11/1215 AM.

There will be a slow cooling trend through Sunday. Despite the cooling most max temps will remain above normal through Sunday. Marine layer stratus and fog will return to most beaches today, then will become more widespread with increasing inland extent Friday through the weekend.

SHORT TERM (TDY-SAT)

11/450 AM.

Srn CA will be under a Cull area for the short term with hgts around 589 dam. At the sfc there will be mdt to stg onshore flow both to the N and the E. A fairly strong eddy has raised the marine layer to at least 2200 ft and has brought low clouds to most cst/vly areas south of Pt Conception. It is also generating a south surge which will bring low clouds up into the waters just west of the Central Coast.

Look for the marine layer stratus to increase in coverage and duration through the period with many beaches seeing slow to no clearing on Friday and Saturday.

Most max temps will cool a few degrees today (The far interior will be the exception and will warm a degree or two), but most of SLO county will see double digit cooling as the offshore flow that warmed the area ydy will not occur today. Look for 2 to 3 more degrees of cooling Friday as the marine layer expands and the onshore push increases. Saturday will see little change in temperatures. Despite all of this cooling almost all max temps will remain above normal through the period with only the beaches seeing normal or slightly blo normal temps. In general the csts will see max temps in the 70s and lower 80s, while the vlys will warm into the mid 80s to lower 90s.

The one fly in the forecast ointment comes from the SW flow around an upper high centered over nrn Mexico. This flow pattern will bring some mid level monsoon moisture up into Srn CA. PWAT may climb to near 1 inch later Friday. At this time it looks like the bulk of the moisture and associated afternoon convection will be just south of LA County in Orange County and esp San Diego County. There is, however, a 10 percent chc that enough moisture will creep upward to bring TSTMs to the LA county mtns.

LONG TERM (SUN-WED)

11/247 AM.

Very June like conditions on tap for the weekend and early next week. Weak high pressure will be overhead with hgts near 591 dam. The mdt-stg onshore flow will continue both to the north and east. This will bring night through morning low clouds and fog to almost all of the coasts and many of the vlys every day.

Look for little or no change in temps on Saturday. On Sunday most areas will cool a few degrees. There will not be much day to day change in temps early next week. Max temps will be near or even a degree or two blo normal across the csts and vlys due to the marine layer and strong onshore flow. The mtns and far interior, however, will end up 5 to 10 degrees above normal due to the higher than normal hgts.

Like Friday, there is a small (5 percent) chance for a shower or thunderstorm over the eastern San Gabriel Mountains Saturday afternoon and early evening.

AVIATION

11/1148Z.

At 0832Z at KLAX, the marine layer was about 2200 ft deep. The inversion top was at 3300 ft with a maximum temperature of 22 C.

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

Moderate confidence in TAFs for KSMX and KSBP where there is 30 percent chc of MVFR cig/vis 13Z-16Z.

Moderate confidence in the remainder of TAFs. Cig hgts may be off by +/- 200 ft and VFR transition could be 1 hour delayed at KBUR and KVNY and up to 2 hours at the rest of the cstl sites.

KLAX...Moderate confidence in TAF. SCT conds could arrive as late as 20Z. Low clouds could arrive as early as 11/02Z. The east wind component is expect to be less than 8 kt.

KBUR... Moderate confidence in TAF. SCT conds could arrive as late as 17Z.

MARINE

11/249 AM.

Good confidence in Small Craft Advisory (SCA) level seas over PZZ670 and PZZ673, with 10 foot seas lingering through this morning. Southerly winds 10-20 knots are likely early today near Point Conception, expanding north through this afternoon. Then conditions are expected to be relatively mild through early next week for much of the coastal waters.

West to northwest wind gusts 15-20 knots (locally 25 knots) will be common each afternoon Friday and through at least early next week across the nearshore waters south of Point Conception (including the Santa Barbara Channel, San Pedro Channel, and Santa Monica Bay).

LOX WATCHES / WARNINGS / ADVISORIES

CA...High Surf Advisory in effect until 8 PM PDT this evening for zones 87-362-366. (See LAXCFWLOX). Beach Hazards Statement in effect through this evening for zone 354. (See LAXCFWLOX). PZ...Small Craft Advisory in effect until 9 AM PDT this morning for zones 670-673. (See LAXMWWLOX).