textproduct: Los Angeles

SYNOPSIS

16/1259 AM.

Night through morning marine layer clouds will continue for the coast and lowers valleys, shrinking in coverage each day into next week. Cooler than normal temperatures continue today, then warmer than normal temperatures return this week, with widespread moderate Heat Risk potentially occurring away from the immediate coast.

LONG TERM (WED-SAT)

16/114 AM.

Upper level ridging will continue to bring warm and dry conditions to Southwest California through the work work. Onshore flow will also be its weakest Wednesday through at least Friday. The resulting widespread Moderate Heat Risk will also lead to a moderate chance for heat headlines away from the coast through at least Thursday, but increasing model agreement for Friday brings it into play as well. The marine layer will likely be confined just to the immediate coastal areas, and there is a small chance that dense fog will occur as the marine layer depth will be quite shallow.

While winds aren't expected to be of any widespread significance, the increasing northerly pressure gradient will allow for gusty north to northwest winds are likely each night across the interior mountains (especially the Grapevine), deserts, and southwest Santa Barbara County. While widespread advisory level winds aren't likely in the extended period either, there is a chance for portions of southwest SB County to reach advisory levels. As in the short term, increasing northerly winds across southwestern SB County could disrupt the formation of marine layer clouds across the south coast of the county as well as Ventura County. Again, this could result in warmer temps along the coasts.

Next weekend still maintains some uncertainty in the evolution of the upper pattern. Cluster analysis still shows fairly similar chances of weak troughing setting up along the coast vs the ridge maintaining its position out west. Suffice to say confidence from Saturday on is fairly low. While the former solution favor a cooling trend, the latter favor continued hot weather and even a small chance for monsoonal convection.

AVIATION

16/1800Z.

At 1719Z at KLAX, the marine layer was at 1300 feet deep. The top of the inversion was near 4600 feet with a temperature of 23 C.

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

Low to moderate confidence in remaining TAFs, lowest south of Point Conception. Arrival times of IFR/MVFR conds tonight may be off +/- 2-3 hours. Patchy marine layer may also cause conds to bounce between VFR and MVFR/IFR later tonight and Mon morning.

KLAX...Low to moderate confidence in TAF. Arrival of cigs tonight may be off +/- 2-3 hours from TAF with 40% chance of IFR. Cloud coverage may bounce between SCT and OVC late tonight and Mon morning. There is also a 20% chance no cigs late tonight. No significant east wind component expected.

KBUR...High confidence in VFR TAF.

MARINE

16/857 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 looks on track. May see a lull in these winds this morning, but winds will quickly increase late this morning through the afternoon.

Good chance for SCA winds to be ongoing from this afternoon/ evening through much of the week over the outer waters, with SCA winds expanding into the northern outer waters Monday afternoon/ evening. Tuesday and Wednesday, local gale force gusts will be possible.

For the inner waters, SCA winds are possible during the afternoon to evening hours for the Santa Barbara Channel today and for the Santa Barbara Channel and inner waters north of Point Sal Monday and Tuesday. Wednesday looks more favorable for SCA winds for the inner waters north of Point Sal. Gusts near 25 kt are possible for portions of the southern inner waters this evening and possibly Monday and Tuesday evenings.

Building short period seas are expected over the next several days, likely rising to around 7-8 feet over the outer waters.

LOX WATCHES/WARNINGS/ADVISORIES

CA...NONE. PZ...Small Craft Advisory in effect from 3 PM this afternoon to 2 AM PDT Monday for zone 650. (See LAXMWWLOX). Small Craft Advisory in effect from 6 PM this evening to 3 AM PDT Monday for zone 655. (See LAXMWWLOX). Small Craft Advisory in effect until 9 AM PDT Monday for zones 673-676. (See LAXMWWLOX).