598 FXUS66 KLOX 191600 AFDLOX Area Forecast Discussion National Weather Service Los Angeles/Oxnard CA 900 AM PDT Thu Jun 19 2025 .SYNOPSIS...19/256 AM. A cooling trend will begin today and continue through Saturday as low pressure develops along the West Coast. Increasing night and morning low clouds and fog are expected as well. Gusty northerly winds are expected across southern Santa Barbara County and through the Interstate 5 Corridor for the next several nights. Below normal temperatures are expected next week. && .SHORT TERM (TDY-SAT)...19/858 AM. ***UPDATE*** The marine inversion this morning ranged from near 900 ft deep at VBG to near 2200 ft deep at LAX. Extensive low clouds covered the coast and vlys of VTU/L.A. Counties earlier this morning, as well as the SBA County S coast and portions of the Central Coast. The low clouds were already starting to clear back to the coast at mid morning, and should clear away from the coast before midday, altho may linger for a while into early this afternoon for the SBA S coast beaches. Otherwise and elsewhere, sunny skies will prevail through this afternoon. There will be a rapid increase in onshore pressure gradients to the N and E today, with the NAM fcst LAX-DAG gradient topping out around 9.7 mb at 00Z this afternoon, while the LAX-BFL gradient reaches 5.7 mb at that time. These onshore gradients will help to bring gusty NW winds to the Central Coast and SW SBA County by mid to late this afternoon, as well as gusty W-NW winds from the I-5 Corridor of NW L.A. County to the Antelope Vly. Winds gusts are expected to reach Advisory levels for SW SBA County and a Wind Advisory is in effect there starting at 4 PM. Breezy to gusty SW- NW winds will affect many other areas this afternoon as well. Temps today will turn several degrees cooler in all areas compared to the last few days, but remain 4-8 deg above normal for most areas, except dropping to a few deg below normal for the Central Coast into the Santa Ynez Vly. The warmest vlys and lower mtns today should reach the mid 80s to mid 90s, except around 100 for the Antelope vly. ***From Previous Discussion*** With high pressure aloft getting pushed east by a low pressure system over the Pac NW, temperatures will be cooling down several degrees across most areas through Saturday except for the immediate coast. Expecting highs today to drop about 5 degrees today and an additional 10 degrees Friday with low clouds starting to work their way into the coastal valleys. The other weather factor the next couple days will be the return of gusty Sundowner winds tonight and again Friday night after a brief one day respite. The strongest winds will be Friday night into early Saturday morning when SMX-SBA gradients get close to -5mb. Could see wind gusts close to 55mph during that time with strong Gale winds across the adjacent coastal waters and Channel Islands as well. .LONG TERM (SUN-WED)...19/329 AM. An upper level trough pattern is expected to continue at least through early next week keeping temperatures a few degrees below normal for the coast and as much as 5-10 degrees below normal for inland areas. Low clouds and fog will push well into the coastal valleys overnight with slower than usual clearing at the beaches. May even have some patchy drizzle at times in the early morning hours. A warming trend is expected to begin Wednesday as high pressure begins to expand from the eastern Pacific. && .AVIATION...19/1013Z. At 10Z over KLAX, the marine layer was 1200 feet deep. The top of the inversion was 4200 feet with a temperature of 27 Celsius. High confidence in VFR TAFs at KPRB, KPMD, and KWJF. Moderate confidence in any lower flight categories staying IFR/MVFR with OVC008-012 most common. Moderate confidence in good clearing at typical times. LLWS 10-20 knots possible at KSBA Friday 01-08Z. KLAX...Moderate confidence in bases staying in the 008-015 range. Clearing to VFR could happen as early as 16Z or as late as 19Z. There is a 30% chance of a brief BKN010 22-01Z. Southeast winds will be prevalent through 17Z, with a 20% chance of exceeding 8 knots. KBUR...Chance of ceilings is now 70%, forming as early as 10Z or as late as 13Z. Moderate confidence in bases at 006-010. High confidence in typical onshore winds. && .MARINE...19/816 AM. Southeast winds will impact the nearshore waters south of Point Conception through this morning, up to around 15 knots in the passages and channels. ***HAZARDOUS SEAS THURSDAY THROUGH SATURDAY*** High confidence in prolonged upper-end Gale Force northwest winds beyond 20 miles from shore from late this afternoon through Saturday night. Moderate confidence in gusts of 30 to 35 knots impacting the nearshore Central Coast waters and western Santa Barbara Channel each afternoon and evening during this stretch. All waters will see building and hazardously steep short period seas. Small craft should stay in safe harbor, especially in the afternoon and evening hours. High confidence in lowering winds and subsiding seas for the first half of next week, with abnormally large high tides each evening. && .LOX WATCHES/WARNINGS/ADVISORIES... CA...Wind Advisory remains in effect from 4 PM this afternoon to 9 AM PDT Friday for zones 349-351. (See LAXNPWLOX). PZ...Small Craft Advisory in effect until 3 PM PDT this afternoon for zones 645-673-676. (See LAXMWWLOX). Gale Warning in effect from 3 PM this afternoon to 3 AM PDT Friday for zone 645. (See LAXMWWLOX). Small Craft Advisory in effect from 3 PM this afternoon to 6 PM PDT this evening for zone 650. (See LAXMWWLOX). Gale Warning in effect from 6 PM this evening to midnight PDT tonight for zone 650. (See LAXMWWLOX). Gale Warning in effect until 3 AM PDT Sunday for zone 670. (See LAXMWWLOX). Gale Warning in effect from 3 PM this afternoon to 3 AM PDT Sunday for zones 673-676. (See LAXMWWLOX). && $$ PUBLIC...MW/Sirard AVIATION...RK MARINE...RK/Lund SYNOPSIS...MW weather.gov/losangeles Experimental Graphical Hazardous Weather Outlook at: https://www.weather.gov/erh/ghwo?wfo=lox