FXUS66 KLOX 022018 AFDLOX Area Forecast Discussion National Weather Service Los Angeles/Oxnard CA 118 PM PDT Sun Jun 2 2024 .SYNOPSIS...02/115 PM. A warming trend will establish through Wednesday due to high pressure aloft building in and weakening onshore flow. The warming trend will be most pronounced away the coast. Closer to the coast, night through morning low clouds and fog will persist with continued moderate to strong onshore flow. && .SHORT TERM (TDY-WED)...02/115 PM. High confidence in a warming trend focused across Coastal Valleys to interior through Tuesday or Wednesday as a modest ridge of high pressure builds into the region. The marine layer should somewhat shelter coastal areas from the warming influence of the ridge. It will also continue to provide night to morning low clouds. The pattern continues to look favorable for patchy drizzle, especially Monday night into early Tuesday. Low confidence in the extent of the marine layer especially into Tuesday due to competing forces between the building ridge pressing down on the marine layer and the potential for a Catalina Eddy acting to prop it up. This leaves us with only moderate confidence in daytime highs across coastal valleys in particular. Daytime highs will likely warm 10-15 degrees between today and Tuesday or Wednesday, except closer to 5 degrees along the coast and perhaps into lower elevation coastal valleys. By Tuesday this will likely result in highs generally in the 70s near the coast, 80s to near 90 for coastal valleys, and 90s to near 100 further inland. Continued northwest flow across the region will support gusty winds at times focused southwest Santa Barbara and the I-5 corridor in the mountains east to the Antelope Valley. A trough passing to the north late Monday may (30-50 percent chance) boost winds into advisory territory. .LONG TERM (THU-SUN)...02/115 PM. The peak of the heat will likely be Wednesday for many areas, although some coastal and coastal valley areas may peak on Tuesday due to offshore trends and the potential for less marine influence on that day. Will maintain the Excessive Heat Watch for Wednesday, covering many far interior areas. However, there is some concern that onshore trends and an earlier sea breeze Wednesday may stall warming for some of these areas even as the ridge peaks in intensity overhead. There is a small chance that the heat hangs on long enough for some interior areas to need some type of heat product into Thursday. Lower confidence in the forecast heading into next weekend as a low pressure system may move into the region from the south or southwest. There is a 10 percent chance (leaving a 90 percent chance that unremarkable early June weather continues) that this setup is favorable for showers or thunderstorms for interior areas and drizzle or light showers for closer to the coast. Either way temperatures should cool at least somewhat, possibly significantly for interior areas should the more active weather scenario play out. && .AVIATION...02/1756Z. At 17Z at KLAX, the marine layer was 3000 ft deep. The top of the inversion was at 5200 feet with a temperature of 17 deg C. Moderate to hi confidence in the 18Z TAFs. Low clouds with IFR/MVFR cigs over the coast and adjacent vlys S of Point Conception will clear to near the coast by early this afternoon, except MVFR cigs are likely to persist thru the afternoon at KOXR and KCMA. IFR/MVFR cigs will likely spread back inland tonight and affect all coast and adjacent vly airfields including KPRB and continue into late Mon morning except scattering out of KPRB by 16Z Mon morning. The timing of the dissipation and onset of low clouds may be off +/- an hour or two, with the largest uncertainty of the onset of low clouds tonight for KSBA and KPRB. For KWJF and KPMD, there is hi confidence VFR conds will continue thru the TAF period. Gusty SW-W winds will affect these airfields for most of the fcst period. KLAX...Moderate to hi confidence in the 18Z TAF. MVFR cigs will likely persist until early this afternoon with a 50% chance of the low clouds scattering out. MVFR cigs will move back in this evening and continue tonight thru Mon afternoon. The timing of dissipation and onset of the low clouds may be off +/- an hour or two. There is a 20% chance of an east wind component of 7-8 kt from 09Z-15Z Mon. KBUR...Moderate confidence in the 18Z TAF. MVFR cigs are expected until about 21Z then VFR conds will prevail into this evening. MVFR cigs should move back in by 06Z this and continue thru the rest of the fcst period. The timing of the dissipation and onset of the low clouds may be off +/- an hour or two. && .MARINE...02/117 PM. For the outer waters, gale force wind gusts can be expected through late tonight and a Gale Warning is in effect. For all the outer waters zones, SCA conds are expected late tonight thru Tue morning, but will also continue (50%-60% chance) for the northern outer waters zone (PZZ670) through Wed night and for the central outer waters (PZZ673) through Tue night. SCA level seas may linger into Thu then all waters will have conds below SCA levels on Fri. In the inner waters N of Pt. Sal, SCA level winds are likely (70-80% chance) during the afternoon/eve hours today and Mon. Though winds will drop off tonight/Mon morning, seas will likely remain near or at advisory levels so the SCA is in effect thru Mon night. SCA conds are not expected Tue thru Fri. In the inner waters S of Pt. Sal, there is a 20% chance of SCA winds in western portion of the SBA Channel during this afternoon/eve, and a 50-60% chance Mon afternoon/eve. Otherwise, conds over the inner waters should be below SCA levels thru Fri. && .LOX WATCHES/WARNINGS/ADVISORIES... CA...Excessive Heat Watch in effect from Wednesday morning through Wednesday evening for zones 344-381>383. (See LAXNPWLOX). PZ...Small Craft Advisory in effect until 3 AM PDT Tuesday for zone 645. (See LAXMWWLOX). Gale Warning in effect until 3 AM PDT Monday for zones 670-673-676. (See LAXMWWLOX). && $$ PUBLIC...Munroe AVIATION...Sirard MARINE...Sirard SYNOPSIS...Hall/RM weather.gov/losangeles Experimental Graphical Hazardous Weather Outlook at: https://www.weather.gov/erh/ghwo?wfo=lox