28/227 AM.
Some coastal low clouds and fog will be possible each night and morning through late next week, otherwise mostly clear skies with warmer temperatures can be expected during the period. Gusty west to north winds will prevail over the mountains and deserts at least through at least Monday.
(tdy-Tue), 28/256 AM.
Not much going on in the short term other than some winds and a slow increase in the amount of night through morning low clouds. The main storm track is well north of the area and NW slightly cyclonic flow will be over the area today and Monday on Tuesday the flow will turn a little more westerly and a little more cyclonic. At the sfc a large high pressure system to the WNW of the Bay Area will bring strong NW winds to the waters and the Central Coast. A meso sfc high near Bakersfield will keep northerly offshore flow going across eastern SBA county, VTA county and western LA county.
The strong WNW flow into western SBA county has produced some back building low clouds in the Santa Ynez vly back into western coastal plain. A weak eddy is forecast by the ensemble to bring low clouds to the KLAX-KLGB area around dawn there is a 40 percent chc that this will not happen. There will be low end advisory (45 mph) gusts across the western Antelope Vly, I-5 corridor and VTA county mtns. There will also be advisory level 45 mph gusts across western portion of the SBA south coast as the strong NW winds whip off of the Pacific and filter through passes and canyons of the western Santa Ynez range. Max temps today will respond nicely to the sunshine and offshore flow - look for 3 to 6 degrees of warming across the board. Most max temps will approach normals but will likely fall just short.
Monday will be much like today just a little better low clouds coverage. The winds will continue through the afternoon. There is a decent chc (30-40 percent) that wind advisories will be need to be extended into Tuesday. Another 1 to 2 degrees of warming will bring max temps to normals or a degree above.
The offshore flow from the north increases to 6mb on Tuesday morning. The canyon winds will likely extend down from the mtns and into the vlys and then the csts as it passes through various N/S passes and canyons. Short range high rez ensembles indicate only a low chc (25 percent) of advisory level winds across VTA/LA counties but a much higher chc (70 percent) across the western half of southern SBA county.
(Wed-Sat), 28/310 AM.
The EC and GFS mean ensembles and deterministic are in generally good agreement thru Thursday with broad pos tilt troffing on Wednesday giving way to NW flow on Thursday. There will only be minimal low clouds on Wednesday mostly across the LA county south coast. Lower hgts and stronger onshore flow will bring 2 to 4 degrees of cooling to most areas. High pressure is fcst to move into NV on Thursday morning and will set up offshore flow from both the N and E. A low end Santa Ana wind event will develop. There will be no low clouds and 3 to 6 degrees of warming.
There is not much mdl agreement either in the deterministic side or ensemble side of things for the Friday and Saturday forecast. fortunately the consequences will not be great the EC fcst will be cooler with more marine layer clouds and the GFS fcst will trend warmer with less marine layer clouds.
28/1041z.
At 09Z at KLAX, the marine layer was 1300 ft deep. The top of the very weak inversion was around 2200 ft with a temp of 14C.
There were low clouds in Santa Ynez Vly and southern portions of the Central Coast, with mostly LIFR-VLIFR conds. Skies should clear by mid/late morning. Some low clouds just N of SLO County may slip into the Salinas Vly for a couple of hours near sunrise, with IFR-LIFR conds. Low clouds just S and W of L.A. County are expected to stay off the coast this morning, with a small chance of high IFR-low MVFR cigs near the coast for a few hours. Low clouds with IFR-LIFR conds are expected in southern portions of the Central Coast and the Santa Ynez Vly tonight, with high IFR- low MVFR cigs possible in coastal sections of L.A. County late. Gusty W-NW winds will affect southern SBA County, the I-5 Corridor and the Antelope Valley and adjacent foothills thru Mon morning.
KLAX, Moderate confidence in TAF. There is a 20% chance of low MVFR to IFR cigs 13Z-17Z today. There is a 30% chance of conds remaining VFR tonight. No east wind component expected.
KBUR, High confidence in TAF with VFR conds thru the pd.
28/321 AM.
Small Craft Advisory (SCA) level winds will become widespread across the outer waters today. A very long period of gale force winds is expected, continuing thru at least Tue night. Winds will occasionally drop below gale thresholds, but for the most part, gales are expected across much of the outer waters much of the time. SCA conds are expected Wed thru Thu, with a 30% chance of gales persisting into Wed evening.
In the inner waters N of Pt. Sal, SCA level winds are likely thru Tue night, especially in the afternoon/eve hours. There is a 50% chance of SCA conds during the afternoon/eve hours Wed/Thu. Seas are expected to be near SCA levels during the periods of weaker winds. There is a 25% chance of gale force winds during the afternoon/eve hours today thru Tue.
In the SBA Channel, SCA level W-NW winds are expected across western portions during the afternoon thru late night hours today thru Wed. There is a 50% chance of SCA conds across the eastern portions late this afternoon and evening, and a 40% chance during the afternoon and evening hours Mon thru Tue.
In the southern inner waters, there is a 40% chance of SCA level W to NW winds across northwestern portions, mainly from Anacapa Island to Malibu during the late afternoon thru late evening hours thru Tue.
Widespread strong to gale force winds will keep dangerous sea conditions across much of the coastal waters (particularly the outer waters) thru the middle of the week, with short-period, steep, and choppy waves. There may be dangerous breaking waves near west-facing harbors. Mariners should plan accordingly.
Ca, Wind Advisory now in effect until 3 PM PDT Monday for zones 349-351. (See LAXNPWLOX). Wind Advisory remains in effect until 3 PM PDT Monday for zones 376>378-381-383. (See LAXNPWLOX). PZ, Small Craft Advisory in effect until 3 AM PDT Wednesday for zone 645. (See LAXMWWLOX). Small Craft Advisory in effect from noon today to 3 AM PDT Monday for zone 650. (See LAXMWWLOX). Small Craft Advisory in effect until 3 PM PDT this afternoon for zone 670. (See LAXMWWLOX). Gale Warning in effect from 3 PM this afternoon to 3 AM PDT Wednesday for zone 670. (See LAXMWWLOX). Gale Warning in effect until 3 AM PDT Wednesday for zones 673-676. (See LAXMWWLOX).
