14/1207 AM.
A warming trend will continue through Wednesday, with dangerous expected for many areas through Thursday. A few showers and thunderstorms may affect the mountains and the Antelope Valley this afternoon. Gusty northwest to north winds are forecast for southern Santa Barbara County and the LA and Ventura interior mountains during the afternoon and overnight hours today and especially Wednesday. Cooler weather will begin to arrive on Thursday.
(tdy-Thu), 14/228 AM.
Over the next three days CA the state will be under the western edge of large and hot upper high. Hgts will wobble between 590 dam and 592 dam. The sfc pressure gradients will be the most important factor in the forecast. The E/W gradient will likely be weakly onshore in the morning becoming mdt onshore in the afternoon. This gradient will also become a little more onshore each day. The N/S gradient will likely be weakly offshore in the morning and weakly onshore in the afternoon. There is a 30 percent chc that there will be offshore flow from the east on Wednesday morning.
The high hgts and weaker than normal onshore flow will team up Today and Wednesday to bring two days of warming. Most areas will see 3 to 6 degrees of warming today with the exceptions of the Antelope Vly which will likely see 8 to 10 degrees of warming and the Central Coast where a stronger sea breeze will bring a little cooling. Wednesday will be the warmest day with another 3 to 6 degrees of warming on tap for the entire area. This warming will bring 100 to 110 degree heat to the vlys, lower mtn elevations and the far interior on Wednesday. The increase in onshore flow will bring some cooling on Thursday, but not enough to eliminate the heat risk. The Extreme Heat Warnings and Heat Advisories in effect for most of the area will persist through Thursday evening. Please see the product LAXNPWLOX for all of the details. During the heat wave, it is very important to avoid the heat of the day as much as possible, especially between 10AM and 7PM.
There will be one more day of monsoonal moisture moving into and over the area within the upper high's circulation pattern. This mositure will bring a 20-40 percent chc of showers/TSTMs to the mountains and Antelope Vly. The highest chc of convection will occur over the eastern San Gabriels and the higher Ventura Mountains.
Strong Sundowner winds are forecast for the SBA south coast with over 4mb of an offshore push from both the KSMX and KBFL gradients. Northerly winds with gusts 30-00 mph will affect most of the SBA south coast tonight. The Sundowner winds will peak Wednesday evening with gust 35-50 mph (local gusts to 60 mph are possible in the foothills). These winds with their adiabatic compressional heating could bring temps in the 90s all the way to the beaches with triple digit heat in the foothills. The hot and dry conditions will greatly increase the fire danger and a Fire Weather Watch is in effect for all of the Santa Barbara South Coast and Mountains Wednesday into Thursday morning.
(Fri-Mon), 14/226 AM.
Very little change in the synoptic pattern during the long term. Hgts will sit around 592 dam through the period. The sfc gradients will be the bigger news as they will both trend onshore and become mdt to stg.
There will be night through morning low clouds and fog across the csts xtng locally into the vlys.
Max temps will nose dive 6 to 12 degrees on Friday. This cooling will bring max temps to or even a few degrees blo normal. After Friday temps will not change much day to day as the synoptic situation will not change much.
PWATs will remain around 1 inch and there will be a non zero chc of some afternoon mtn showers, but more likely just some cloud build ups. Long range mdls do show a generous uptick in moisture due to the movement of a tropical system next Tuesday.
14/1130z.
At 0832Z at KLAX, the marine layer depth was 1000 ft. The top of the inversion was at 2100 ft with a max temperature of 26 C.
High confidence in TAFs for KPRB, KSBP, KSBA, KBUR, KVNY, KPMD and KWJF.
Moderate confidence in TAFs for KSMX, KOXR, KCMA and KLGB with a 30 percent chc of IFR cigs 13Z-17Z.
Fair confidence in TAF for KSMO and KLAX with a 30 percent chc of low MVFR cigs and that VFR conds arriving within an hour of fcst.
There is a 15 percent chance of TSRA at KPMD/KWJF from 14/18Z through 15/01Z. These storms would be capable of producing erratic winds, turbulence and heavy rainfall.
KLAX, Fair confidence in TAF. There is a 30 percent chc of BKN010-012 cigs through 17Z. Good confidence that VFR conds will arrive between 16Z-18Z. No significant east wind component expected.
KBUR, High confidence in TAF.
14/153 AM.
NW winds are expected to strengthen to Small Craft Advisory (SCA) levels across the Outer Waters this afternoon and will continue through Thursday night. There is also 20% chance of Gales later Wednesday into Thursday. Seas are forecast to build over 10 feet in conjunction with these winds. The elevated winds and seas will extend into the western Santa Barbara Channel and nearshore waters along the Central Coast at times through this period, mainly during the afternoon and evening hours. While a few showers may drift across the local waters through early parts of this week, thunderstorms are unlikely.
14/154 AM.
Dangerous rip currents and breaking waves with elevated surf are expected for coastal areas and the beaches of Los Angeles, Ventura, Santa Barbara, and San Luis Obispo Counties, as enhanced southerly swell continues. A Beach Hazards Statement remains in effect through Wednesday evening for these areas. Minor coastal flooding will be possible during the evenings, given abnormally high tides of 7.0 to 7.6 feet. Later this week and into the weekend, distant storms over the East Pacific waters well south of the area could produce increasing southerly swell resulting in even more significant beach hazards by the weekend.
Ca, Heat Advisory remains in effect until 10 AM PDT this morning for zones 38-88-343>345-353-368-372-373-375>380-548. (See LAXNPWLOX). Extreme Heat Warning in effect from 10 AM this morning to 8 PM PDT Thursday for zones 38-88-349>353-356>358-368>375-378>383-548. (See LAXNPWLOX). Heat Advisory remains in effect from 10 AM this morning to 8 PM PDT Thursday for zones 87-341>345-347-348-354-355-362-366-367-376-377-549-550. (See LAXNPWLOX). Beach Hazards Statement in effect through Wednesday evening for zones 340-346-349-350-354-362-366. (See LAXCFWLOX). Fire Weather Watch in effect from Wednesday afternoon through Thursday morning for zones 349>353-376>378. (See LAXRFWLOX). PZ, Small Craft Advisory in effect from 3 PM this afternoon to 9 PM PDT this evening for zone 650. (See LAXMWWLOX). Small Craft Advisory in effect from noon today to 3 AM PDT Friday for zone 670. (See LAXMWWLOX). Small Craft Advisory in effect from 3 PM this afternoon to 3 AM PDT Friday for zone 673. (See LAXMWWLOX). Small Craft Advisory in effect from 6 PM this evening to 3 AM PDT Friday for zone 676. (See LAXMWWLOX).
