14/835 AM.
Slight warming is expected for today and Friday. Gusty winds are expected at times across the mountains and deserts. Hazardous seas are expected for the coastal waters over the weekend. Above normal temperatures are possible early next week.
(tdy-Sat), 14/833 AM.
***UPDATE***
The marine inversion deepened to near 3000 ft at LAX this morning. Low clouds were fairly extensive over the L.A. County coast and vlys this morning but were confined to the VTU/SBA County S coast. Low clouds were also noted along the Central Coast to the Santa Ynez Vly. These low clouds are forecast to clear back to or off the coast by this afternoon. Otherwise, mostly sunny skies will prevail today as an H5 580-582 dam ridge parks itself over the forecast area. Breezy to locally gusty SW-W winds can be expected by this afternoon across the region.
Temps today are forecast to be from a few degrees below normal along the coast into the adjacent vlys to several degrees above normal for the interior vlys, mtns and deserts. Afternoon highs will be in the 60s along the immediate coast coast, 70s for the inland coast and adjacent vlys, 80s for the interior vlys and lower mtns, and upper 80s to low 90s for the deserts.
***From Previous Discussion***
Weak ridging will continue over the area through Friday, then Saturday a dry inside slider trough will begin to impact the region. 500 mb heights will be fairly consistent through Friday, then fall rapidly Saturday with the approaching trough. Moderate- to-strong onshore flow will continue each day, with an increase in northwesterly flow starting Friday. Northwest to westerly winds with gusts between 20 to 35 mph will occur late this afternoon and tonight along the Central Coast, Southwestern Santa Barbara County, the Antelope Valley, and the interior mountains (including the Interstate 5 corridor). Winds across the same areas will be stronger Friday afternoon into Saturday morning (and again Saturday afternoon into Sunday morning), with gusts of 40 to 55 mph possible for Southwestern Santa Barbara County (mainly the western Santa Ynez Range), and interior mountains and deserts. Some local Wind Advisories may be issued for these time periods.
500 mb heights and onshore flow support the possibility of low clouds each morning across all the coasts and valleys. However cold northwest flow aloft has weakened the marine layer inversion, thus cloud coverage may be patchy, especially for areas north of Point Conception. The greatest chances for low clouds will be this morning and Friday morning across LA/Ventura Counties, when northwest flow aloft will be weaker. Daytime highs will be mild, with coasts and valleys in the upper 60s to upper 70s. East of the mountains, interior valleys and deserts will see highs in the 80s, with the warmest day expected to be Friday.
(Sun-Wed), 14/344 AM.
The inside slider trough will impact the region through the weekend. Strong northwest to westerly winds will continue Saturday into Sunday across much of San Luis Obispo and Santa Barbara Counties, all beaches, and the interior mountains and deserts. Early next week, as the trough moves out the area to the east, 500 mb heights will gradually trend upwards. Additionally there is around a 30 percent chance of periods of weak offshore flow, particularly Monday and Tuesday mornings. Northeast wind gusts of around 20 to 30 mph will be possible across the wind prone mountains. If offshore flow does occur, coastal temperatures have the potential to warm into the upper 70s and low 80s, otherwise highs in the 60s will be favored. Overall a warming trend is expected Monday through Wednesday, with the highest confidence for inland areas. Away from the beaches, highs will increase from mid 70s to mid 80s on Monday, to low 80s to around 90 degrees on Wednesay (5 to 10 degrees above normal). Marine layer low clouds and fog will be possible each day across the coast and valleys.
14/1156z.
At 0649Z at KLAX, the marine layer was 2500 ft deep. The top of the inversion was at 5900 ft with a temperature of 16 C.
High confidence in VFR TAFs for KPMD and KWJF.
Moderate to low confidence in remaining TAFs. Timing of CIG/VSBY restrictions may be off +/- 2 hours and flight minimums off by one category. Expecting mostly MVFR/IFR conditions. Clouds may arrive 2-3 hrs later than forecast, with a 30-40% chance of not at all, especially at KBUR, KVNY, KSBA, KCMA, KOXR and KSMX. There is a 30% chance of a couple hours of MVFR cigs from 14Z-17Z Thu at KSBP.
KLAX, Moderate confidence in TAF. Arrival and clearing times of CIGs may be off +/- 2 hours. 20% chance of the east wind component reaching 6 kt until 17Z Thu.
KBUR, Moderate confidence in TAF. Arrival and clearing times of CIGs may be off +/- 2 hours, with a 40% chance of not forming at all.
14/823 AM.
GALE WARNINGS have been issued. Refer to MWWLOX for details.
For the outer waters from the Central Coast to San Nicolas Island, high confidence in Small Craft Advisory (SCA) winds and seas lasting through tonight. STRONG GALES are expected Friday through the weekend with large 10-15+ foot steep seas.
Periods of SCA conditions are expected for the nearshore Central Coast waters through Friday morning. STRONG GALES are expected from Friday afternoon through Sunday evening. There is also a moderate chance for GALES across the Santa Barbara Channel and the western portion of the southern waters Saturday into Sunday.
These dangerous sea conditions could capsize or damage small and large vessels. Mariners should adjust plans NOW to remain in safe harbor.
14/824 AM.
Over the weekend, the combination of high winds and seas could result in hazardous surfing conditions and minor coastal flooding especially across more unprotected west-facing beaches such as along the Ventura coastline. Stay tuned for future updates.
Ca, NONE. PZ, Small Craft Advisory in effect until 9 AM PDT this morning for zone 645. (See LAXMWWLOX). Small Craft Advisory in effect from 3 PM this afternoon to 9 PM PDT this evening for zone 645. (See LAXMWWLOX). Gale Watch in effect from Saturday morning through Sunday evening for zone 645. (See LAXMWWLOX). Small Craft Advisory in effect until 9 AM PDT Friday for zone 670. (See LAXMWWLOX). Gale Watch in effect from Friday morning through late Sunday night for zone 670. (See LAXMWWLOX). Small Craft Advisory in effect until 3 PM PDT Friday for zone 673. (See LAXMWWLOX). Gale Watch in effect from Friday afternoon through late Sunday night for zone 673. (See LAXMWWLOX). Small Craft Advisory in effect until 6 PM PDT Friday for zone 676. (See LAXMWWLOX). Gale Watch in effect from Friday evening through late Sunday night for zone 676. (See LAXMWWLOX).
