Forecast Discussions mentioning any of "ACARS" "MDCRS" "AIRCRAFT" "TAMDAR" "AMDAR" "WVSS" received at GSD on 02/14/20

Area Forecast Discussion
National Weather Service Los Angeles/Oxnard CA
804 PM PST Thu Feb 13 2020 .SYNOPSIS...13/749 PM. Temperatures for Friday and this weekend will be near to slightly above normal as high pressure remains over the region. Areas of coastal night to morning clouds are expected through Saturday, and some breezy conditions will develop over southern areas on Sunday. && .SHORT TERM (THU-SUN)...13/804 PM. Current satellite imagery showing marine layer clouds redeveloping this evening across portions of the Central Coast. 00Z Vandenberg sounding showing the marine layer depth around 1500 feet with a fairly well established marine inversion. Some patchy dense fog is also possible overnight into early Friday morning across the Salinas Valley. For areas south of Point Conception, the marine layer depth is shallower with a weaker inversion, as evident by the ACARS data showing a depth around 800 feet across the LA basin. As a result, expecting low clouds and fog to mainly be confined to the coastal areas for LA/Ventura counties. Little change in temperatures expected on Friday, with pressure gradients near neutral in the early morning, becoming weakly onshore once again in the afternoon hours. *** From previous discussion *** A weak and short-lived ridge nudges in from the west on Saturday. With weak offshore trends expected, there may be a limit as to the formation of marine layer stratus. Again the most likely locations will be the Central Coast and southern LA County coast. Otherwise another sunny day and temperatures will warm a few degrees, with low 70s expected in the valleys. On Sunday the ridge gets squashed by an inside slider moving into the Pacific Northwest. It won`t really affect our weather much other than increase onshore flow and lead to slight cooling along the coast. .LONG TERM (MON-THU)...13/222 PM. The inside slider then digs southward into Nevada on Monday. However, it does not dig as sharply as was previous forecasted. Northerly pressure gradients will increase, but not quite as drastically as previous model runs indicated. There will also be less cold air advection associated with it than previously thought. However, advisory level northerly winds are still possible for at least the LA mountains. Otherwise there will be some high clouds and temperatures over the mountains and interior valleys will cool by several degrees. By Tuesday through late week, the models diverge quite a bit. The ECMWF indicates the trough pushing to the south while a ridge noses in for Wednesday and Thursday keeping things dry. However, the GFS indicates that the trough lingering Tuesday and cuts off into a closed low just along the coast of Point Conception on Wednesday. Ensembles don`t really support any precipitation with this solution, so have kept the forecast dry with partly cloudy skies. Winds transition from the north to northeast during this period. Gradients continue to look decent, so there will be the potential for advisory level winds over Santa Ana prone areas. && .AVIATION...13/2355Z. At 2355Z, the marine inversion at KLAX was based at 700 feet. The top of the inversion was 1700 feet with a temperature of 13 degrees Celsius. North of Point Conception, moderate to high confidence in 00Z TAFs. For tonight, high confidence in return of IFR/LIFR conditions, but low to moderate confidence in timing. South of Point Conception, moderate confidence in coastal TAFs and high confidence in valley/desert TAFs. CAVU conditions for all sites through this evening. For later tonight into early Friday morning, high confidence in return of IFR conditions to KLAX/KSMO/KLGB, but low confidence in timing. For KCMA/KOXR, there is a 30% chance that CIG/VSBY restrictions will not develop. For KSBA, there is a 30% chance of IFR conditions 09Z-17Z. KLAX...Overall, moderate confidence in 00Z TAF. High confidence in CAVU conditions through this evening. For tonight, high confidence in return of IFR conditions, but only moderate confidence in timing (could be +/- 2 hours of current 10Z forecast). No significant easterly wind component expected. KBUR...High confidence in 00Z TAF as CAVU conditions are anticipated through TAF period. && .MARINE...13/735 PM. For the Outer Waters, high confidence in current forecast. Through Saturday, winds and seas will remain below Small Craft Advisory (SCA) levels. On Sunday, there is a 60% chance of SCA level northwesterly winds. On Monday and Tuesday, there is an 80% chance of SCA level northwesterly winds and seas. For the Inner Waters north of Point Sal, moderate to high confidence in current forecast. Through Saturday, high confidence in winds and seas remaining below SCA levels. On Sunday and Monday, there is a 60-70% chance for SCA level northwesterly winds with conditions expected to drop below SCA levels on Tuesday. For the Inner Waters south of Point Conception, moderate to high confidence in current forecast. Generally high confidence in winds and seas remaining below SCA levels through Tuesday. The only exception will be the western half of the Santa Barbara Channel where there is a 50% chance of SCA level northwest winds on Sunday and Monday. && .LOX WATCHES/WARNINGS/ADVISORIES... CA...NONE. PZ...NONE. && .HAZARD POTENTIAL OUTLOOK (SUN-THU). Gusty northerly winds are likely Sunday night into Monday, then transitions to a Santa Ana wind event Tuesday and Wednesday. && $$ PUBLIC...Gomberg/Stewart AVIATION...Gomberg MARINE...RAT/Gomberg SYNOPSIS...Phillips