Area Forecast Discussion
Issued by NWS Los Angeles, CA
Issued by NWS Los Angeles, CA
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699 FXUS66 KLOX 091643 AFDLOX Area Forecast Discussion National Weather Service Los Angeles/Oxnard CA 943 AM PDT Sun Jun 9 2024 .SYNOPSIS...09/914 AM. Temperatures will continue to be on the cooler side today, except for the Central Coast where there will be better clearing of clouds. Then high pressure aloft will warm temperatures and decrease onshore flow Monday and Tuesday. Otherwise, night through morning low clouds will continue across the coast and valleys through the middle of next week. && .SHORT TERM (TDY-TUE)...09/924 AM. ***UPDATE*** Marine layer depth is around 3000-3500 feet across the LA Basin and sloping down to around 2000 feet across SLO/SB Counties. It was another damp morning in many areas due to drizzle from the marine layer, though amounts were lower than yesterday. It`s going to be another cool day across the area due to strong onshore flow in place slow resulting in slow clearing of the low clouds. Highs expected to be 5-10 degrees below normal. However, with earlier clearing expected north of Pt Conception highs there are expected to be a few degrees warmer than yesterday. ***From Previous Discussion*** Regionwide, temperatures will trend upward Monday through Tuesday, when the cutoff low stalls to the south. This will be because of higher hights over the region and a general decrease in onshore gradients, that will limit daytime cloud cover and afternoon seabreezes. However the marine layer will still follow June Gloom patterns each day, extending into the valleys in the mornings and clinging to many coasts all day. The afternoon LAX to DAG gradient is expected to remain strong (despite the slight weakening) through at least Tuesday (between 7 to 9 MB), and will continue to fuel gusty southwesterly winds in Antelope Valley and foothills. .LONG TERM (WED-SAT)...09/355 AM. The cut-off low will remain in place Wednesday and much of Thursday. Thursday evening through Friday the upper low will travel eastward just south of the region. The low will heavily influence temperatures, which will trend downward each day through Thursday. Precipitable water anomalies are expected to be well below normal when the low passes just south of the region, and maximum vorticity will occur during the stable overnight hours. As both these components limit the potential for precipitation, stratiform rain or convective activity is unlikely. Beginning Friday and continuing into Saturday, there is good agreement among the models that a strengthening East Pac high will bring a strong sfc gradient across, especially the coastal waters. This would drive very strong northwest to north winds across the region, including a significant Sundowner Wind event. Additionally, temperatures are expected to trend upward and cloud cover will trend downward due to the the shift to an northerly offshore pattern, especially for areas like the deserts, Paso Robles, and the Santa Barbara South Coast. Beyond Saturday, the GFS and ECMWF both show indications that northerly winds and temperatures will continue to increase into early next week. && .AVIATION...09/1643Z. At 1630Z at KLAX, the marine layer was 2900 ft deep. The top of the inversion was at 4800 ft with a temperature of 17 degrees C. High confidence in 18Z desert TAFs. Moderate confidence in 18Z coastal and valley TAFs. Timing of flight category changes could be +/- 2 hours of current forecasts. There is a 20-30% chance that coastal TAFs south of Point Conception may not clear this afternoon. KLAX...Moderate confidence in 18Z TAF. There is a 30% chance that MVFR CIGs will not scatter out this afternoon. Timing of flight category changes could be +/- 2 hours of current forecasts. There is a 30% chance of IFR CIGs 05Z-16Z. No significant easterly wind component is expected. KBUR...Moderate confidence in 18Z TAF. Timing of flight category changes could be +/- 2 hours of current forecasts. && .MARINE...09/739 AM. Moderate to high confidence in the current forecast. For the Outer Waters, there is high confidence of Small Craft Advisory (SCA) level winds through early Monday, then winds and seas remain below SCA levels between Monday and Thursday. For the Inner Waters north of Point Sal, there is high confidence of SCA level winds this afternoon and evening, then winds and seas will remain below SCA levels between late Sunday night and Thursday. For the Inner Waters south of Point Conception, there is a 30-40 percent chance of SCA level winds late this afternoon and evening across the western half of the Santa Barbara Channel. Otherwise, winds and seas are expected to remain below SCA levels through Thursday. && .LOX WATCHES/WARNINGS/ADVISORIES... CA...NONE. PZ...Small Craft Advisory in effect from 3 PM this afternoon to 9 PM PDT this evening for zone 645. (See LAXMWWLOX). Small Craft Advisory in effect until 3 AM PDT Monday for zones 670-676. (See LAXMWWLOX). Small Craft Advisory in effect until 9 AM PDT Monday for zone 673. (See LAXMWWLOX). && $$ PUBLIC...MW/Schoenfeld/Rorke AVIATION...RAT MARINE...Rorke/RAT SYNOPSIS...MW/Hall/RS weather.gov/losangeles Experimental Graphical Hazardous Weather Outlook at: https://www.weather.gov/erh/ghwo?wfo=lox