06/136 PM.
Rain due to distance tropical cyclone Marie will continue into this evening, focused over Los Angeles and portions of Ventura Counties. A significant southerly swell will create hazardous surf conditions at the beaches trough at least Tuesday. Heat will build in the region over the next several days, with moderate to major heat impacts across the coasts and valleys Tuesday through Thursday.
(tdy-Wed), 06/225 PM.
Moisture from Hurricane Marie has hitched a ride within the cyclonic flow along the bottom of a rather strong (for the time of year) trough centered over Oregon. Forecasted track for Marie still keeps her very much well off the California Coast, she is currently around 750 NM south-southwest of Los Angeles and traveling northwest to north and weakening.
Rain totals so far across Los Angeles County have been around 0.25 to 0.75 inches. Ventura County saw lower rain amounts along the edge of the moisture, mostly under 0.25 inches. Minimal rain fell across Santa Barbara County so far. Rain rates for many areas remained low to moderate, with brief periods of higher rates within heavier showers. Rain chances will continue through the afternoon with an additional 0.10 to 0.25 inches possible for LA and Ventura Counties. There will also continue to be a 15 percent chance of a thunderstorm this afternoon for Los Angeles County, especially if some sunshine is able to make it to the surface. This evening, rain chances will dimish, and very patchy, but dense fog will be possible overnight.
Starting Monday, a significant warming trend is expected. By Tuesday expect lots of areas of moderate to major HeatRisk for the coasts and coastal valleys, in particularly the LA Basin. Temperatures are expected to peak on Wednesday, with widespread major HeatRisk and highs largely 90 to 105 degrees. There is the potential that Heat Advisories will be needed (even near the coast) as early as Tuesday, becoming likely for Wednesday for most all coasts and valleys. Along the Central Coast, Tuesday is favored to remain cooler with a very dramatic warming trend for Wednesday, when temperatures could be in excess of 100 degrees. The warming trend for the region is due to a combination of a high pressure ridge that is likely to center over SoCal this week, along with periods of weak offshore flow. Very warm overnight lows (even at the coasts) and elevated humidity will contribute to the heat impacts.
A weak impulse acting on lingering low level moisture may A boundary lifting back north later Monday and especially into Tuesday may support another round of light to moderate showers, and cannot rule out an isolated thunderstorm focused across interior mountains.
Some of Marie's most hazardous impacts for the region is at the beaches. Ongoing large and potentially deadly surf and rip currents are focused across south and southwest facing beaches, as well as moderate coastal flooding. If entering the ocean, we recommend swimming near a life guard. This threat continues through at least Tuesday, please see marine and beaches discussions for more details.
(Thu-Sun), 06/200 PM.
Upper level ridge of high pressure expected to remain strong over the area on Thursday, then weaken some on Friday. During this time, pressure gradients will likely be weakly offshore to the north and weakly onshore to the east, resulting in a continuation of hot temperatures with associated heat impacts across much of the region on Thursday, with a slight cool-down possible by Friday. There is also the potential for some weak to moderate sundowner wind activity across southern Santa Barbara county each evening on Thursday and Friday.
The position of the ridge by Thursday may be favorable for some monsoon moisture or injection of tropical moisture from the south. So it will likely be quite humid with weak morning offshore flow potentially delaying the sea breeze. This type of pattern could support isolated showers focused across the interior.
Below normal confidence Friday into next weekend as the ridge may break down pretty quickly or be somewhat stubborn. Either way it does look somewhat likely that troughing off the coast may reestablish at times, keeping the door open for additional subtropical moisture to shuttle into southwest California.
06/1853z.
At 1824Z at KLAX, the marine layer was 700 ft deep with a very weak inversion up to 2000 ft with a maximum temperature of 20 C.
Rain or showers are expected for Ventura and Los Angeles County TAF sites through the day today, likely ending between 22Z Sun and 02Z Mon. Ceiling heights will mostly be VFR with period of MVFR, though VSBY may fall to 1-2SM briefly during heavier showers. There is also a 5-15 percent chance of a thunderstorm for Ventura and Los Angeles TAF sites, until around 00Z Mon.
KLAX, Moderate confidence in TAF. Cigs will generally be between BKN025-BKN100 for the day, and VSBY falling to as low as 2SM occasionally with heavier rain through around 02Z Mon. East wind component exceeding 8 kts is possible (40% chance) through 23Z, and confidence is generally low in wind direction until 00Z Mon.
KBUR, Moderate confidence in TAF. Cigs will generally be between BKN025-BKN100 for the day, and VSBY falling to as low as 2SM occasionally with heavier rain through around 02Z Mon.
06/131 PM.
For the Outer Waters, through Monday morning SCA level winds and seas are expected, with a lull on Monday and Tuesday. Wednesday afternoon into at least late next week SCA winds are likely much of the time.
For the Inner Waters north of Point Sal, there is a 30% chance of SCA level winds on Wednesday evening and a 60% chance for Thursday. Otherwise conditions are expected to be below SCA levels.
For the Inner Waters south of Point Conception, there is a 50% chance of brief SCA level winds Tuesday afternoon and evening, and a 30-50% chance of SCA winds across western sections on Thursday. Otherwise conditions are expected to be below SCA levels.
Tropical moisture will stream over the area today and last into Tuesday, bringing showers to the coastal waters. There is a 15% chance of thunderstorms this afternoon for the waters south of the Channel Islands. A large southeast to south swell is impacting the area, causing increased currents and surges in the vulnerable harbors. Breaking waves may impact south harbor entrances, particularly for Ventura and Los Angeles Counties (observed at Ventura Harbor).
06/239 PM.
Significant coastal impacts are expected across Southern California beaches through at least Tuesday. A large southeast to south swell from Hurricane Marie has moved into waters this weekend with swell heights of 5-7 feet and a period around 13 seconds.
High surf conditions are expected on south-facing beaches of Ventura and Los Angeles counties, peaking at 5-8 feet with local sets to 12 feet through Monday. Potentially life threatening rip currents will continue as well. The highest surf is near Zuma and Malibu Beach as well as Long Beach. The Santa Barbara South Coast will be largely protected from this swell, but there are some small windows of southeasterly and southwesterly energy that could cause boosts in the waves. HIGH SURF ADVISORIES remain in place for Los Angeles and Ventura Counties, with BEACH HAZARDS STATEMENTS (a step below high surf advisories) in effect for Santa Barbara and San Luis Obispo Counties.
Moderate coastal flooding has occurred and will continue around high tides for south facing shores. The actual observed tides have been running about 6 inches above predictions for sometime now. The south swell will likely boost that enhancement. As a result, high tides are expected to reach around 6.7 feet by 6 pm today, then exceed 7 feet by Monday evening high tide. Expect significant beach erosion, flooded sandy beach areas, bike paths, and parking lots, as well as low-lying roads. Of particular concern will be the Alamitos Peninsula area in Long Beach where coastal flooding will potentially cause local damage to structures near time of high tide later today, Other areas of concern the next couple of days include Catalina Island, and Oxnard to Malibu (including Point Mugu). COASTAL FLOOD ADVISORIES remain in effect for Los Angeles and Ventura Counties where the best combination of tides and waves will occur, but Santa Barbara and San Luis Obispo Counties could also see some isolated issues.
Ca, Coastal Flood Advisory in effect until 11 PM PDT Tuesday for zones 87-354-362-366. (See LAXCFWLOX). High Surf Advisory in effect until 11 PM PDT Tuesday for zones 87-354-362-366. (See LAXCFWLOX). Beach Hazards Statement in effect through Tuesday evening for zones 340-346-349-350. (See LAXCFWLOX). PZ, Small Craft Advisory in effect until 9 AM PDT Monday for zones 670-673-676. (See LAXMWWLOX).
