Area Forecast Discussion
Issued by NWS Los Angeles, CA
Issued by NWS Los Angeles, CA
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494 FXUS66 KLOX 091740 AFDLOX Area Forecast Discussion National Weather Service Los Angeles/Oxnard CA 940 AM PST Sun Nov 9 2025 .SYNOPSIS...09/923 AM. A warming and drying trend will continue into Monday as a ridge of high pressure continues to build aloft and offshore flow at the surface continues. Temperatures above seasonal levels are likely through Monday, with highs in the 80s and 90s across most coastal and valley locations. A storm system will move over the region during the latter half of next week and could bring moderate to heavy rainfall. && .SHORT TERM (TDY-TUE)...09/938 AM. ***UPDATE*** Big contrast in temperatures today from coast to valleys as the offshore gradients materialized but without any upper support. So for now coastal areas south of Pt Conception are still dealing with areas of dense fog and much cooler temperatures while just a few hundred feet above sea level temperatures are already in the 80s. May still get a little Santa Ana influence across interior portions of the coast across LA/Ventura Counties but the biggest warming trend today will be inland. May need to issue a quick update for beaches to account for the cooler temps, otherwise everything on track today and with likely 1-3 degree bump in temps Monday. ***From Previous Discussion*** High pressure aloft will continue to build over SW CA through Monday before weakening and shifting eastward on Tuesday. As the high pressure builds, the offshore gradients will continue to strengthen a little bit through Monday morning. Currently, marine layer clouds are stretching all across the coasts of the four counties, with some some clouds sneaking into the San Gabriel Valley, a small patch in the eastern San Fernando Valley (right over Burbank airport), and into the Ventura County inland Coast (and up to the top of the Conejo Grade). While a Dense Fog Advisory is in place until 9 AM for the Malibu Coast as well as the Ventura Coast and Inland Coast, the rest of the coastal and inland coastal areas may see areas of patchy dense fog down to a quarter mile visibility or less. As for tonight, marine layer clouds may make a return to the coasts if the offshore flow remains weak enough, and patchy dense fog will be possible again into Monday morning anywhere these clouds may form. Otherwise, skies are expected to clear through Monday. By Tuesday morning, there will be the chance of some stratus/fog returning to coastal areas. Please slow down and leave a larger gap for the vehicle in front if dense fog is encountered while driving. As for temperatures, a warm up across the region is still expected these next two days thanks to the ridge of high pressure aloft and the offshore flow. High temperatures are expected to reach into the 80s to 90s by Monday, with a little bit cooler temperatures at the immediate coasts. These temperatures will be around 10-15 degrees above normal for this time of year. Some locations will approach record highs, but do not anticipate any record breaking readings. One caveat, however, is if the offshore gradients end up being weaker than the models are forecasting, which would result in cooler temperatures, especially across the LA Basin. Overnight lows will also be warm, especially across the foothills and valleys. As for winds, the offshore flow is on the weaker side this morning (around -2 mb for both offshore LAX gradients), with the pressure gradients forecast to reach around -4.0 and -2.6 mb (LAX-DAG and LAX-BFL, respectively) Monday morning. The offshore flow, with weak upper level support and lack of cold air advection, will result in a weak (maybe barely moderate) Santa Ana event, with gusty winds across the typical Santa Ana Corridor of Ventura and Los Angeles Counties as well the Santa Lucias this morning and tonight into Monday morning. Expecting winds to remain below advisory levels, with a isolated mountain locations reaching around 45 mph. .LONG TERM (WED-SAT)...09/334 AM. Overall for the extended period, models continue to be on the same synoptic page with a wet and unsettled period of weather. Unfortunately, there still are still differences in the details (timing, amounts, etc.), so not much change in the forecast at all for the extended. On Wednesday, increasing clouds and cooler temperatures can be expected as storm system approaches the West Coast. Some light warm frontal precipitation will be possible Wednesday evening, ahead of the storm. For Thursday and Friday, both the deterministic GFS/ECMWF and their respective ensembles indicate a storm will roll across the area and will bring significant measurable rainfall to the area. However, the ECWMF and its ensembles (as well as the ECWMF-AIFS) are slower with the progression of the system and generate more significant rainfall than the GFS and its respective ensemble members. With these differences, confidence in the forecast details remains on the low to moderate side. Current best forecast estimate is for a widespread 1-2 inch rain event across coasts and valleys, and 2-4 inches across mountains and foothills. As mentioned before, there is quite a wide range across model outcomes, so there remains a 30% chance of a lesser event, or a heavier event including some convective potential. As for rain rates and specific burn scar concerns, it really depends on the tilt of the trough, direction of flow, and the convective potential, so it is still too early to come up with reasonable rain rates. Additionally, based on thicknesses, snow level look like they could drop to around 6000 feet and the resorts could see some decent snow accumulations. However, much like with rain totals, confidence in the exact snow levels remain on the low to moderate side. By late Monday or Tuesday, the window for the higher resolution models opens up, so hoping by Tuesday, there will be more model agreement and details can be fine tuned. && .AVIATION...09/1650Z. At 1630Z at KLAX, the marine layer was 500 feet deep. The top of the inversion was 1800 feet with a temperature of 26 degrees Celsius. For 18Z TAF package, high confidence in desert and valley site, but low to moderate confidence for coastal sites. There is a 40% chance that VLIFR conditions do not develop at KSBP and KSMX tonight. For coastal sites south of Point Conception, there is a 30% chance of LIFR/VLIFR conditions developing after 06Z. KLAX...Overall, moderate confidence in 18Z TAF. There is a 30% chance of LIFR/VLIFR conditions 06Z-17Z. No significant easterly wind component is expected. KBUR...High confidence in 18Z TAF. && .MARINE...09/850 AM. For the Outer Waters, moderate to high confidence in current forecast. Today through Wednesday, high confidence in winds and seas remaining below Small Craft Advisory (SCA) levels. For Thursday, high confidence in a combination of SCA level winds and seas developing. There will be a 30% chance of Gale force winds on Thursday across PZZ670/673. For the Inner Waters north of Point Sal, moderate to high confidence in current forecast. Today through Wednesday, high confidence in winds and seas remaining below SCA levels. For Thursday, high confidence in a combination of SCA level winds and seas developing. There is a 40% chance of Gale force winds on Thursday. For the Inner Waters south of Point Conception, moderate to high confidence in current forecast. Today through Wednesday, high confidence in winds and seas remaining below SCA levels. On Thursday, there is a 50% chance of SCA level winds with even a 20% chance of Gale force winds Thursday evening. Areas of dense fog will impact the coastal waters this morning. Visibilities of one nautical mile or less can be expected. && .LOX WATCHES/WARNINGS/ADVISORIES... CA...NONE. PZ...NONE. && $$ PUBLIC...MW/Thompson/Lund AVIATION...RAT MARINE...RAT SYNOPSIS...MW/Hall/KL weather.gov/losangeles Experimental Graphical Hazardous Weather Outlook at: https://www.weather.gov/erh/ghwo?wfo=lox