143 FXUS66 KLOX 100033 AFDLOX Area Forecast Discussion...UPDATED National Weather Service Los Angeles/Oxnard CA 533 PM PDT Tue Oct 9 2018 Updated aviation section .SYNOPSIS...09/114 PM. Cooler conditions will continue through Thursday, but slightly warmer temperatures going into the weekend. Night through morning low clouds will return to the coastal areas and will decrease towards the end of the week. High surf is expected Tuesday through Friday. && .SHORT TERM (TDY-FRI)...09/137 PM. Skies are mostly clear over the forecast area this afternoon with the exception of a few clouds along the central coast. Breezy conditions are expected in Antelope valley this afternoon with southwest flow. Afternoon high temperatures should be similar to yesterday's with the exception of the Antelope Valley where things are running about 3-5 degrees warmer. Expecting our upper-level trough to deepen a bit on Wednesday which will further deepen the marine layer. This deepened marine layer and orographic lift could bring some night to morning drizzle to the valleys, foothills and coastal slopes. The lower heights tomorrow and deep marine layer will cool things 3 to 5 degrees across the entire forecast area. Clearing will again be pretty slow and there is a chance that the skies above the coastal areas will only clear to partly cloudy. The upper level trough is still expected to elongate along its SW to NE oriented axis on Thursday. There will be another round of extensive low cloud coverage. There is a chance of some patchy drizzle near the coastal slopes and foothills. There should be slightly better clearing with some surface gradients trending offshore and this should allow the coast and coastal valleys to have a degree or two of warming over Wednesday. Afternoon high temperatures across the interior will remain the same or even cool a degree as heights fall with the elongating trough. Numerical guidance continues to diverge on Friday. All agree to make a weak cut-off low from the base of the trough. The EC then quickly moves the low to our south and east by Saturday morning, while the GFS moves it very slowly in an arc from our west on Friday until moves over San Diego on next Tuesday. This is one of those patterns that the models struggle with. As far as Friday goes, there will be some additional height falls and GFS and NAM indicate the surface gradients will turn offshore at about -3 mb. There will be much less of a marine layer and clouds will be mostly confined to the LA coast. Afternoon high temperatures will jump everywhere about 3 to 5 degrees. .LONG TERM (SAT-TUE)...09/154 PM. The long term forecast is very low confidence due to the stark differences in numerical guidance. The EC forecasting warmer temps and less of a marine layer due to higher heights while the GFS is the opposite due to the lower heights and cyclonic turning from the upper low. Model spread in the EC and GFS ensembles seems to indicate the EC is less certain of its solution so have tended the long range to favor the GFS, although would not be surprised to see that model speed up its solution for moving the cut-off low out of the area. Expecting the offshore winds to end by Sunday and a marine layer to return for Monday and Tuesday mornings. Temperatures will be near seasonal with a warm up is expected early in the week. && .AVIATION...10/0022Z. At 23Z, the marine layer depth was around 2500 feet deep at KLAX. The top of the inversion was at 3400 feet with a temperature near 16 degrees Celsius. Low to moderate confidence in the current forecast. Timing could be up to two to four hours earlier than forecast. IFR to MVFR conditions will likely spread into coastal terminals through 08Z, then into valley terminals through 13Z. There is a chance of conditions lowering one category between 10Z and 16Z. KLAX...There is a 40 percent chance of MVFR conditions at 03Z increasing to 90 percent by 07Z. There is a 30 percent chance of IFR conditions in drizzle or light showers between 11Z and 16Z. There is a 40 percent chance that VFR conditions could develop as soon as 17Z. Any east winds should remain less than 7 knots. KBUR...There is a 40 percent chance of MVFR conditions at 07Z increasing to 90 percent by 11Z. There is a 30 percent chance of IFR conditions in drizzle or light showers between 11Z and 16Z. There is a 50 percent chance that VFR conditions could develop as soon as 17Z. && .MARINE...09/151 PM. Moderate to high confidence that winds will remain below SCA levels across the waters through at least Saturday. Large, moderate-period south to southwest swell will affect much of the waters beginning tonight and persist through Friday, and may persist into the weekend. && .BEACHES...09/915 AM. Hazardous surf conditions including dangerous rip currents will likely redevelop once again this morning or this afternoon, then build through at least Thursday night. The increased surf dangerous rip conditions will be from what is now left of Hurricane Sergio which is weakening and should be downgraded to a Tropical Storm tonight or tomorrow. Estimates of surf heights between 6 to 9 feet with sets to 11 feet during the peak of the event. The highest surf will be observed at south and southwest facing beaches. Surf should begin to subside late Friday, but there is a chance that dangerous and strong rip currents could linger into Saturday. In addition, there will be the potential for some minor to moderate coastal flooding during peak of the high surf combined with high tides. && .LOX WATCHES/WARNINGS/ADVISORIES... CA...Beach Hazards Statement in effect through Friday afternoon for zones 34-35-40-41-87. (See LAXCFWLOX). PZ...NONE. && .HAZARD POTENTIAL OUTLOOK (FRI-TUE). High surf and dangerous rip current are likely across south and southwest facing beaches through Friday as additional swell energy from Sergio moves into the coastal waters. Minor/moderate coastal flooding will also be possible during times of high tide along low lying areas due to the combination of high surf and fairly high tide levels. Locally gusty offshore winds are possible Friday with low humidities and elevated fire danger. && $$ PUBLIC...jld AVIATION...Hall MARINE...Sweet BEACHES...Sweet SYNOPSIS...Delerme weather.gov/losangeles