Area Forecast Discussion
Issued by NWS Los Angeles, CA
Issued by NWS Los Angeles, CA
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690 FXUS66 KLOX 111753 AAA AFDLOX Area Forecast Discussion...UPDATED National Weather Service Los Angeles/Oxnard CA 953 AM PST Tue Nov 11 2025 updated aviation discussion .SYNOPSIS...11/913 AM. Onshore flow will return to the region today as a ridge of high pressure continues to weaken and shift eastward. A shallow marine layer will bring dense fog at times to the coast, possibly reaching the valleys by Wednesday morning. A trough of low pressure will approach the West Coast on Wednesday night and bring rain, heavy at times through Thursday night or Friday and possibly into Saturday as well. && .SHORT TERM (TDY-THU)...11/922 AM. ***UPDATE*** Onshore flow has returned and cooler temperatures are on the way for valleys and inland areas today and tomorrow. Could even see some low clouds and fog getting into some of the valleys by Wednesday morning. Models are starting to throw some curve balls at us for this next storm, particularly with the timing as many of the solutions are now are slowing it way down, and potentially lingering well into Saturday. AI models have been generally slower but now the 12z deterministic models are showing that as well. In fact, some models maintain a persistent south to southeast flow well into Saturday with possibly another burst of moderate to heavy rain Saturday afternoon. Will see what the 12z GEFS/ENS ensembles show later this morning before making any big changes, but the pattern is looking at least slightly delayed and wetter for a longer duration than originally expected. ***From Previous Discussion*** A moderate to strong storm with PW`s around 1.5" is expected to move through the region during the latter half of the week. Could see some light precip as early as Wednesday night along the Central Coast and a few post- frontal showers Friday, but 90% of the rainfall should take place on Thursday. Most areas will experience around 6-8 hours of precip with the front, 1-3 hours of which could be heavy with up to 0.75" per hour and a 20% chance of as much as 1.00" per hour. The heaviest precip will be in the usual favored upslope areas, including the Santa Lucia`s, the Santa Barbara mountains (particularly the Santa Ynez Range) into the western Ventura County mountains, the Santa Monica mountains, and the eastern San Gabriel mountains. All of those areas will be at risk for heavy rain and flooding. If models stay consistent it`s likely that a Flood Watch will be issued for the most vulnerable areas, including the most recent burn scars. Projected total rain amounts remain about the same with most coastal/valley areas falling into the 1-2" range with foothills and south facing mountains in the 2-4" range. But would not be surprised to see a couple 5" totals when all is said and done. Additionally, there is a slight chance of thunderstorms along San Luis Obispo and Santa Barbara counties on Thursday, and most of the region by Friday morning. Any thunderstorm that may form may be accompanied by lightning, locally gusty winds, heavy downpours, and/or small hail. Not expecting any snow below 8000 feet with this system until the very tail end of it, when there could be a few inches between 6000-8000 feet. .LONG TERM (FRI-MON)...11/253 AM. There is still some uncertainty with regard to how long showers will continue following the main cold front on Thursday. The latest ensembles place the trough right through LA County Friday morning with northwest flow developing during the afternoon and evening. There still could be some brief moderate to locally heavy showers before the trough passage Friday morning but most of the ensembles are indicating rain rates well below a half inch per hour after 4am Friday. Some of the ensemble members of both the GFS and EC hint at rain continuing over the weekend, (which may just be why the NBM is carrying slight chances of rain over the entire weekend), however the majority of ensemble members suggest the rain is over before the day changes to Saturday. Therefore, dry but cool weather is expected over the weekend. There remains a small chance of a weak storm next Monday but recent model runs have backed off that system. && .AVIATION...11/1753Z. At 17Z at KLAX, the marine inversion was around 300 ft deep. The top of the inversion was near 2300 feet with a temperature of 25 degrees Celsius. High confidence in VFR conditions for KVNY, KWJF and KPMD thru Wed morning. Moderate confidence in the 18Z TAFs for all coastal sites along with KPRB and KBUR. Moderate confidence in return of cigs after 00Z, except after 12Z at KPRB and KBUR, but low confidence in timing (+/- 2 hours) and minimum flight cat (off +/- one cat). KLAX...Low to moderate confidence in the 18Z TAF. Arrival of low clouds tonight may be off +/- 2 hours. Moderate confidence in minimum flight cat, and there is a 20% chance VLIFR conds may not develop or last as long. No significant east wind component is expected. KBUR...Moderate confidence in the 18Z TAF. There is a 50% chance of low clouds and IFR conds from about 14Z-17Z Wed, altho the arrival of any low clouds may be off +/- an hour or so. && .MARINE...11/818 AM. Dense fog with visibilities less than one nautical mile will continue to be an issue for all the coastal waters through late this morning. High confidence in relatively calm winds and seas through Wednesday, except for localized Small Craft Advisory (SCA) level wind gusts to 25 knots near Point Conception and south to San Nicolas Islands this afternoon and evening. Southwest winds 20-30 knots will develop Wednesday afternoon across the outer waters as well as nearshore along the Central Coast. Southerly winds across the inner waters south of Point Conception will be in the 15-20 knot range, but SCA level gusts to 25 knots cannot be ruled out. A cold front from a storm system will pass through the region Thursday and gusty northwesterly winds of 20-30 knots will develop across the entirety of the coastal waters. There is a 30% chance for low end Gale Force winds Thursday afternoon through late Friday, including across the inner waters south of Point Conception. Seas across the outer waters will increase to 12-14 feet, and 5-7 feet inside the Southern California Bight. From Wednesday night through Thursday, the aforementioned storm system will bring a slight chance of thunderstorms across the coastal waters from the Santa Barbara Channel northward. Any thunderstorms that develop will be capable of producing frequent lightning, gusty and erratic winds, locally rough seas and even waterspouts. Moderate confidence in conditions improving some over the weekend, but SCA winds are still possible, especially across the outer waters. && .LOX WATCHES/WARNINGS/ADVISORIES... CA...NONE. PZ...NONE. && $$ PUBLIC...MW/KL AVIATION...Sirard MARINE...Lewis/Sirard SYNOPSIS...MW/Hall/KL weather.gov/losangeles Experimental Graphical Hazardous Weather Outlook at: https://www.weather.gov/erh/ghwo?wfo=lox