


Area Forecast Discussion
Issued by NWS Los Angeles, CA
Issued by NWS Los Angeles, CA
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134 FXUS66 KLOX 171621 AFDLOX Area Forecast Discussion National Weather Service Los Angeles/Oxnard CA 921 AM PDT Fri Oct 17 2025 .SYNOPSIS...17/909 AM. Offshore flow will continue through Saturday and keep a warmer and drier pattern in place. Breezy offshore winds will continue this morning, especially through and below passes and canyons. A cooling trend will begin Sunday and continue most of next week with a return of low clouds and fog to the coastal areas. && .SHORT TERM (TDY-SUN)...17/920 AM. ***UPDATE*** Offshore flow ended up being about 30% weaker than forecast but there are still some breezy northeast winds across parts of LA/Ventura Counties this morning. Winds are mostly under 30 mph and generally confined to the valleys and mountains. May still see some light offshore breezes reach the Ventura County coast but at most around 20mph. The biggest impact from this weak Santa Ana will be the warming temperatures. At 9am temps are 5-15 degrees warmer than Thursday, with highs projected to be in the upper 70s and 80s except a little cooler at the beaches. Very little change in highs Saturday. ***From Previous Discussion*** In wind-sheltered areas, clearer skies and dry conditions will permit radiative cooling processes to be much more efficient tonight and into Saturday morning. As a result, Saturday morning could start out a little chillier in wind-sheltered locations, such as the Ojai and Santa Ynez Valleys, and across the interior portions of the area, such as the Antelope and Cuyama Valleys. A cooling trend will start to take shape on Sunday as offshore flow starts to break down and be replaced by an onshore flow regime. A return of night through morning low clouds and fog could return as soon as Sunday morning but more likely for Sunday night and into Monday morning. With the marine layer depth returning in a shallow layer, dense fog could become a hazard to start the week for the coastal areas. .LONG TERM (MON-THU)...17/252 AM. Onshore flow will continue to establish through early next week as a weak upper-level trough to the southwest of the region near 30N and 125W will gradually lift out across the region through Wednesday. While the deterministic solutions mostly keep the region dry with this trough, about a fifth of the latest EPS ensemble members have light precipitation developing over the area between Tuesday and Wednesday. Despite the outlier nature of the wetter solutions, it should be noted that troughs to the southwest of the region are typically not modeled correctly. Due to the data-sparse region, low pressure areas to the southwest of the region are a problematic feature to model. It is not surprising to see the AI solutions of the EPS to have even more members with precipitation. Confidence is high in a deep marine layer with cooler temperatures, but caution should used in the precipitation forecast. For now, NBM values remain in the forecast, but this wrinkle in the forecast will likely need some time to get ironed out. && .AVIATION...17/1530Z. At 1500Z at KLAX, 1Z, the marine layer was 400 ft deep. The top of the inversion was at 1900 ft with a temperature of 20 degrees Celsius. Overall for the 18Z TAF package, high confidence in forecasts for most sites as CAVU conditions are expected. The only exception will be KPRB where there is moderate confidence in the development of CIG and/or VSBY restrictions after 12Z. Weak offshore winds this morning may generate some light turbulence and LLWS through the passes and canyons. KLAX...Overall, high confidence in current forecast as CAVU conditions are expected through the period. There is a 5-10% chance of LIFR/VLIFR conditions 11Z-16Z. No significant easterly wind component is expected. KBUR...High confidence in 18Z TAF as CAVU conditions are expected through the period. && .MARINE...17/830 AM. Overall, high confidence in current forecast for all the coastal waters. Today through Tuesday, winds and seas are expected to remain below Small Craft Advisory (SCA) levels. There will be a good chance of some patches of dense fog this weekend into early next week. && .LOX WATCHES/WARNINGS/ADVISORIES... CA...NONE. PZ...NONE. && $$ PUBLIC...MW/Hall AVIATION...RAT MARINE...RAT SYNOPSIS...MW/Hall weather.gov/losangeles Experimental Graphical Hazardous Weather Outlook at: https://www.weather.gov/erh/ghwo?wfo=lox