29/910 AM.
Hot and muggy conditions will linger in some areas through today, followed by with widespread improvement by Sunday. More warm, tropical moisture could return Tuesday through Thursday. Marine layer clouds will gradually redevelop, and increase in coverage Sunday into early this coming week.
(tdy-Tue), 29/1243 PM.
The cooling trend is here; temperatures this morning compared to yesterday's temperatures at the same time (24 hour temp change) were down by at least 3 to 7 degrees regionwide. Even with today's cooling, temperatures today will remain warm (6-10 degrees above normal) and humid for portions of the area. Thus the Heat Advisory remains in effect for the coasts and valleys of Ventura and Los Angeles Counties as well as the Santa Barbara South Coast through 8 pm tonight. More noticeable cooling is expected for Sunday, followed by below normal temperatures by Monday due to trough to the north impacting the region.
Last night, winds across southwestern Santa Barbara County gusted to 30 to 40 mph. Tonight both surface pressure gradients and high resolution models indicate an increase in wind strength, thus 40 to 50 mph gusts are expected this evening into night for the area, and a Wind Advisory has been issued.
Some marine layer clouds may develop this evening especially along the Central Coast, and are likely to spread farther inland than last night. South of Point Conception, marine layer clouds are less likely to form, but pockets of low clouds and fog cannot be ruled out. Going forward, the marine layer is likely to become more established with greater inland coverage by Monday morning, due to falling 500 mb heights, less mid and upper level moisture, and increasing onshore flow.
Tuesday and Tuesday night, there is around a 20 percent chance of showers and thunderstorms focused over LA and Ventura County. This is a result of more tropical mositure that may be shuttled into the region, as the bottom of an upper level trough dips into SoCal.
(Wed-Sat), 29/1249 PM.
There is a small chance that tropical moisture and thus showers and thunderstorm risk will linger into Wednesday, but is most likely to be dry. Otherwise mostly quiet weather with a gradual warming trend is favored for Wednesday into the following weekend. An upper level troughing pattern appears likely for a fairly long duration, which will maintain a robust marine layer at the coasts and coastal plains. Somewhere around September 7-9th there are signals for another round of tropical moisture to impact SoCal.
29/1936z.
At 1816Z at KLAX, there was no marine layer nor inversion.
Overall, moderate to high confidence TAFs. Low confidence in any marine layer clouds forming tonight, highest chances would be for KSBP and KSMX. There is a 60% chance of VFR conditions through the period for KSMX.
KLAX, High confidence in TAF. There isa 10% chance of BKN008 conds 12-17Z Sun. Good confidence in any east wind component remaining below 7 kt.
KBUR, High confidence in TAF.
29/1241 PM.
Through this weekend, high confidence in Small Craft Advisory winds and choppy seas for the outer waters. These hazardous conditions will reach into the nearshore waters along the Central Coast and into the Santa Barbara Channel at times (especially during the afternoon/evening hours). Local gusts may approach 35 kt near Point Conception this afternoon and evening. For next week, most waters are likely to fall below SCA levels Monday and Tuesday. Increasing chances for SCA conditions later in the week, highest on Thursday afternoon through Friday.
Ca, Heat Advisory in effect until 8 PM PDT this evening for zones 88-349-350-354>358-362-366>375-548. (See LAXNPWLOX). Wind Advisory in effect from 6 PM this evening to 6 AM PDT Sunday for zones 349-351. (See LAXNPWLOX). PZ, Small Craft Advisory in effect until 3 AM PDT Sunday for zones 645-650. (See LAXMWWLOX). Small Craft Advisory in effect until 3 AM PDT Monday for zones 670-673-676. (See LAXMWWLOX).
