


Area Forecast Discussion
Issued by NWS Los Angeles, CA
Issued by NWS Los Angeles, CA
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120 FXUS66 KLOX 170306 AFDLOX Area Forecast Discussion National Weather Service Los Angeles/Oxnard CA 806 PM PDT Thu Oct 16 2025 .SYNOPSIS...16/804 PM. A light Santa Ana pattern will occur on Friday, bringing warmer temperatures to the area along with locally breezy northeast winds. Dry weather will continue into next week but with cooler temperatures. && .SHORT TERM (TDY-SAT)...16/805 PM. ***UPDATE*** Models continue to show good agreement through the short term, including the surface pressure and heights aloft. A high pressure ridge will build into the area from the west tonight into Friday, with a weak cutoff low developing SW of Point Conception Friday into early next week. At the surface, an offshore high pressure center will build inland through Oregon, settling into the Great Basin by 5 AM Friday morning. With a 1021 mb surface high over Nevada and an inverted trough of low pressure along the SW California coast, weak offshore gradients are expected to strengthen overnight. The NAM shows -3.0 mb for the LAX to Daggett gradient at 5 AM, slightly stronger than earlier model runs depicted. With only limited upper level support expect the event to be sub- advisory, however some localized advisory level gusts could occur in the most favored locations for Santa Ana winds. Over the valleys expect peak gusts to be 25 to 30 mph, with 35 to 40 mph in the mountains, including the interior mountains of LA and Ventura Counties, and the western Santa Monicas. Otherwise, expect clear skies overnight with lows in the 50s for the coasts and valleys, 40 to 50 for the Antelope Valley and dipping into the 30s over wind sheltered interior areas. Highs on Friday will be up anywhere from 3 to 10 degrees from today`s highs. This means mid 70s to mid 80s across the area, with 50s to 60s over the mountains. ***From Previous Discussion** For Friday afternoon through Sunday, a diurnal flow pattern will continue with weakening offshore flow in the morning hours and gradually increasing onshore flow in the afternoon hours. So, with the weakening offshore gradients, do not anticipate any concern for advisory- level winds Friday night or Saturday night. Otherwise, no significant issues are expected. Overall, clear skies are expected although there is a chance that some stratus and fog could return to the coastal plain late Saturday night and Sunday morning. As for temperatures, the weak offshore flow in the morning hours, rising thicknesses and limited marine influence will allow for a warming trend for all areas through Saturday. By Sunday, there will be some slight cooling for the coastal plain with persistence/slight warming for interior sections. .LONG TERM (SUN-WED)...16/115 PM. For the extended, 12Z models continue to exhibit decent synoptic agreement. begin to show some synoptic differences, but nothing that will greatly impact the forecast. Upper low will continue to spin southwest of the area on Monday then will move eastward across the area Tuesday/Wednesday with a trough approaching the West Coast on Thursday. Forecast-wise, no significant issues are expected through the period. The upper low does not appear to entrain any moisture as it moves across the area. So, at this time, the chances for any measurable precipitation are very low (less than 10%). However, the lowering H5 heights and the return of weak onshore flow, the marine layer stratus/fog should gradually increase in depth and areal coverage. Other than the stratus/fog, skies should remain mostly clear through the period. As for temperatures, will expect a general cooling trend for all areas through Wednesday with some slight warming in some inland areas on Thursday. && .AVIATION...16/2321Z. At 2237Z, the marine layer was 800 ft deep. The top of the inversion was at 1900 ft with a temperature of 19 C. Overall, high confidence in VFR TAFs for all sites except KPRB. For KPRB, there is a 40% chc for VFR conditions, but if CIGs form there is a similar chance for 1/4SM. Northeast wind gusts (up to 20 kts) may surface at KSBP from 06Z to 15Z Friday. LLWS is possible at KSBP,KOXR, KCMA, KBUR, and KVNY through the period, especially if winds remain aloft and do not surface. Light to moderate turbulence is possible, especially over any mountainous terrain. KLAX...High confidence in 00Z TAF. VFR conditions with no wind issues expected through period. KBUR....High confidence in 00Z TAF with VFR conditions expected. Light to moderate LLWS and turbulence (especially over mountainous terrain) is possible as northeast winds within 2000 ft of the surface will peak in 30-40 knot range (15Z to 21Z Friday), but these winds are not expected to surface. && .MARINE...16/804 PM. For the waters southwest through northwest of the Channel Islands and outside the southern California bight, Small Craft Advisory (SCA) level northwest winds will continue across the waters from Point Sal south to San Nicolas Island through tonight into Friday morning, with winds strongest near Pt Conception & Pt Arguello. Conditions will remain relatively benign Friday through the weekend, except for localized northeast winds of 20-25 knots nearshore from Cayucos Point/Morro Bay south to Pismo Beach early Friday morning into the early afternoon. There is a 30% chance for SCA conditions roughly 50 NM from shore early next week. Inside the southern California bight, winds are expected to remain below SCA levels through early next week, with the exception of localized nearshore N-NE SCA level winds between Ventura Harbor and Point Dume late tonight into Friday morning (40% chance). Lower chances late Friday night into Saturday morning but focused more around Point Dume. Due to the localized nature of the winds, any chance of a Small Craft Advisory issuance is very low. && .LOX WATCHES/WARNINGS/ADVISORIES... CA...NONE. PZ...Small Craft Advisory in effect until 9 PM PDT this evening for zone 645. (See LAXMWWLOX). Small Craft Advisory in effect until 3 AM PDT Friday for zones 670-676. (See LAXMWWLOX). Small Craft Advisory in effect until 9 AM PDT Friday for zone 673. (See LAXMWWLOX). && $$ PUBLIC...Thompson/Ciliberti AVIATION...Black MARINE...Black/Lewis SYNOPSIS...MW/CC weather.gov/losangeles Experimental Graphical Hazardous Weather Outlook at: https://www.weather.gov/erh/ghwo?wfo=lox