30/247 AM.
Temperatures will become dangerously hot in many areas Friday through the upcoming weekend, as the next heat wave arrives. Some cooling is expected next week, though temperatures will remain above normal. Dangerous surf conditions are expected at area beaches this week into this weekend, as a result of swells from a distant tropical cyclone located west of Mexico.
(tdy-Sat), 30/915 AM.
***UPDATE***
The extra marine layer clouds along the south coast has temperatures down a few degrees from yesterday at this time, but still expecting the afternoon to heat up. No impactful changes to the forecast at this time.
***From Previous Discussion***
Overall the forecast remains largely unchanged as high pressure is expected to push in from the east over the next few days. The marine layer is still exerting its influence during the morning hours with a depth of around 2000 feet in LA, sloping down to around 1000 feet along the Central Coast. However, that influence will be decreasing as high pressure builds over the next couple days, potentially resulting in some areas of dense morning fog near the coast Friday morning. After that it will be all about the heat as a nearly 600dam high moves over the area. Valleys and interior areas will see highs well over 100 Friday and Saturday while intermediate areas between the coast and the valleys (including Downtown LA) will be in the upper 80s to mid 90s. Current forecast highs are mostly within a degree or two of daily records with Saturday having the the highest chance for that. In addition to the traditional daytime heat threat, overnight lows will remain well above normal in response to the very warm ocean temperatures, so there won't be as much relief at night as we are accustomed to. Areas closer to the coast where there are typically fewer homes with AC will be the ones that are impacted most by this.
A large south swell from Tropical Cyclone Genevieve will further enhance large wave and potentially deadly rip currents for some area beaches.
(Sun-Wed), 30/334 AM.
A slow cooling trend is expected to begin Sunday, though temperatures will still be 5-10 degrees above normal and increasing moisture aloft will limit overnight cooling and keep humidities higher than normal. And in addition, high pressure aloft will continue to dominate the weather pattern along the West Coast all of next week, meaning highs will remain above normal for the foreseeable future. Heat hazards may continue into next week.
30/0207z.
At 23Z at KLAX, the marine layer was 800 feet deep. The top of the inversion was 2400 feet with a temperature of 26 degrees Celsius.
For 00Z TAFs, moderate to high confidence. For TAFs near the coast and in the coastal valleys, CIG/VSBY restrictions with night through morning fog may vary from forecasts by 3 hours in timing and by 1 flight category. High confidence in VFR TAFs for interior sites.
KLAX, Moderate confidence in TAF. There is a 40% chance for onset and dissipation of flight restrictions to vary by up to 3 hours from the current forecast. There is a 40% chance for minimum flight category to vary by up to 1 level from current forecast. No significant easterly wind component is anticipated.
KBUR, Moderate confidence in TAF. There is a 40% chance cigs fail to reach the TAF site Thursday AM.
30/906 AM.
For the Outer Waters, Small Craft Advisory (SCA) winds and seas will occur through the remainder of this week through into this weekend, before subsiding early next week.
For the Inner Waters north of Point Sal, there is an 80% chance for SCA winds each afternoon and evening through Saturday. For the Inner Waters south of Point Conception, there is 40% chance of SCA winds each afternoon and evening through this weekend over the western one-third of the Santa Barbara Channel.
Additionally seas of 8-12 feet will impact the outer waters into this weekend, owing to a long-period southerly swell from a distant tropical cyclone, combining with shorter-period northwesterly swell/wind waves resulting from the moderate to strong NW winds. As a result, steep, hazardous seas will be common over especially the outer waters, extending to the coast especially for the Central Coast.
30/906 AM.
Hurricane Genevieve is generating long period S-SE swells that will affect the beaches for the remainder of this week into this weekend. A High Surf Advisory is in effect for the south facing beaches of LA and Ventura Counties through Saturday afternoon. Very strong, severe rip currents have been reported from some area beaches, with a risk of strong long-shore currents and sneaker waves. Use extra caution if you are at the beach, and be sure to ask lifeguards if and where it is safe to swim.
Please reference the Coastal Hazard Message for details on High Surf and Coastal Flood Advisories, as well as Beach Hazards Statements. Dangerous rip currents will be of particular concern this weekend.
Ca, Extreme Heat Warning in effect from 10 AM Friday to 8 PM PDT Sunday for zones 38-88-343>345-351>353-355>358-368>376-378-379-548. (See LAXNPWLOX). Coastal Flood Advisory in effect until 3 AM PDT Saturday for zones 87-354-362-366. (See LAXCFWLOX). High Surf Advisory in effect until 5 PM PDT Saturday for zones 87-354-362-366. (See LAXCFWLOX). Beach Hazards Statement in effect through Saturday afternoon for zones 340-346-349-350-356. (See LAXCFWLOX). Heat Advisory in effect from 10 AM Friday to 8 PM PDT Sunday for zones 341-342-347>350-354-362-366-367-377. (See LAXNPWLOX). Heat Advisory in effect until 10 AM PDT Friday for zones 378-379. (See LAXNPWLOX). Heat Advisory in effect until 8 PM PDT Sunday for zone 380. (See LAXNPWLOX). Extreme Heat Warning in effect until 8 PM PDT Sunday for zones 381>383. (See LAXNPWLOX). PZ, Small Craft Advisory in effect from 3 PM this afternoon to 3 AM PDT Friday for zone 645. (See LAXMWWLOX). Small Craft Advisory in effect until 5 AM PDT Monday for zones 670-673-676. (See LAXMWWLOX).