24/1200 AM.
Hotter than normal conditions will continue for the foreseeable future, generally hottest through Sunday. The hot daytime and warm night conditions will bring elevated risks for heat illness. Gusty north winds will affect some areas through Friday.
(tdy-Mon), 24/1220 PM.
The persistent ridge of high pressure aloft will drive the overall weather through the forecast period. The center of the upper level high is parked over the Four Corners, leaving Southwest California on the western periphery of the highest 500 mb heights. Widespread Heat Advisories and an Extreme Heat Warning remain in effect through Monday night for almost the entire forecast area. The Central Coast remains the only location outside of any Heat Headlines, however, there is a 30% chance Heat Advisories will be needed for the interior Central Coast Sunday and Monday. Temperatures have been a little cooler than forecast in this area the last few days, so we will have to see how things play out today and tomorrow. Onshore flow will continue to bring some afternoon relief at the immediate coastal areas, but not much beyond this.
Expecting some marine layer cloud coverage to return to the Central Coast each night and morning, with chances increasing across the LA Coasts over the weekend. Very low confidence in how the marine layer will behave over the Ventura County and southern Santa Barbara Coast tonight, but with increasing NW winds over the Santa Ynez Saturday and Sunday, expecting little if any marine layer cloud coverage from Southern Santa Barbara County to the Ventura/LA County border. The extent of the marine layer cloud coverage may make or break high temperature forecasts for coastal and inland coastal areas, especially along the Central Coast. As referenced earlier, the Central Coast has been a little cooler than expected the last few days, mostly due to fairly expansive marine layer cloud coverage in the morning slowing down the warm up.
There remains a very low chance for afternoon showers or thunderstorms over the weekend, around 5-10% chance with best chances appearing to be on Sunday.
(Tue-Fri), 24/1220 PM.
Warmer than normal temperatures will continue through the next week, adding to this lengthy warm spell. As mentioned before, the large area of high pressure will remain the dominant weather feature through next week. The core of the high will shift a little to the east Monday through Wednesday and bring a touch of relief to the heat, but only by a few degrees. Coastal areas will see the most noticeable drop as onshore pressure gradients strengthen some and low clouds and fog will likely be more expansive than it has been.
The majority of the ensemble solutions, especially with the EC, show this relief being short-lived as the high pressure builds back towards the west after Wednesday. Some projections show the core of the upper level high moving directly over California by Saturday, with 500 mb heights increasing to close to 600 decameters, which is about as strong as it gets. Because of this synoptic setup, some ensemble projections (and the mean) favor slightly warmer temperatures by the end of next week compared to this current stretch of warmer than normal temperatures. While onshore flow is still projected to be fairly persistent, some ensemble members do show weakening onshore flow late next week into the weekend. If this comes to fruition, coastal areas may see the largest increase in temperatures next weekend compared to this weekend. The one saving grace is that the majority of projections also show a sharp drying trend at the same time, with precipitable water readings dropping from 1.5 inches today to under 1.0 inches by Wednesday. This will certainly help with the muggy feeling weather. The more limited moisture and
24/2338z.
At 2203Z at KLAX, the marine layer was 800 ft deep. The top of the inversion was 3600 ft with a max temperature of 30 C.
High confidence in VFR TAFs for KPMD, KWJF, KBUR, KVNY, KPRB, KSBA.
Moderate confidence in remainder of TAFs.
Chances for LIFR/IFR: KSMX (80%), KSBP (60%). Chances for IFR/low- end MVFR: KOXR/CMA (20% BRIEF around 12Z) KSMO (50%), KLAX (60%), KLGB (60%).
KLAX, High confidence in VFR TAF through 06Z. Arrival & clearing times of CIGs 009 (+/- 300ft) may be off +/- 2 hours. There is a 30-40% chance that CIGs do not arrive or remain brief. High confidence in any east winds staying under 6 knots.
KBUR, High confidence in VFR TAF. No wind issues expected.
24/1224 PM.
High confidence in persistently strong NW winds from the Central Coast to San Nicolas Island through at least Tuesday Night. Gusts of 30-40 knots will be common each afternoon and night, bordering between strong Small Craft Advisory (SCA) and low-end Gale Warnings. These winds will also affect the western Santa Barbara Channel each night, and may cover enough of the channel to need a SCA. With these winds, widespread choppy or steep seas is likely. In addition, patches of dense fog are possible anywhere through Sunday or Monday, especially off the Central Coast.
24/1224 PM.
A long period, southern hemisphere swell will arrive early Saturday and will add to the continuing swell from Hurricane Fausto. This swell will result in an increased risk of dangerous rip currents across the coastal beaches, as well as elevated surf of 3-6 ft across the Los Angeles and Ventura County Beaches. Therefore, Beach Hazard Statements are in effect through the weekend for Los Angeles and Ventura County beaches and the Central Coast beaches. Rip currents and elevated surf will be strongest across south to southwest facing beaches and harbors such as Avila Beach.
The Eastern Pacific looks to remain active with tropical systems over the next couple of weeks. This could result in additional southerly swells to impact the coastline.
Ca, Heat Advisory remains in effect until 8 PM PDT Monday for zones 38-88-342>345-348>358-362-366>382-548. (See LAXNPWLOX). Beach Hazards Statement in effect through Sunday evening for zones 340-346-354-362-366. (See LAXCFWLOX). Extreme Heat Warning in effect until 8 PM PDT Monday for zone 383. (See LAXNPWLOX). PZ, Small Craft Advisory in effect until 3 AM PDT Saturday for zone 645. (See LAXMWWLOX). Gale Warning in effect until 3 AM PDT Saturday for zone 670. (See LAXMWWLOX). Small Craft Advisory in effect until 3 AM PDT Sunday for zones 673-676. (See LAXMWWLOX).
