FXUS66 KLOX 282133 AFDLOX Area Forecast Discussion National Weather Service Los Angeles/Oxnard CA 233 PM PDT Fri Jun 28 2024 .SYNOPSIS...28/232 PM. Temperatures will gradually warm through this weekend, and then become very warm to hot for next week. Dangerously hot conditions are expected next week over interior areas, where daily high temperatures of up to 100 to 105 degrees will be possible, with high temperatures upwards of 105 to 115 possible over interior valleys and foothills including the Antelope Valley. && .SHORT TERM (TDY-MON)...28/232 PM. Midlevel heights will gradually rise over the region this weekend into early next week, as an upper-level ridge builds westward from the south-central states. Surface pressure gradients will be neutral to moderately onshore. This pattern will maintain night and morning low clouds and fog in the marine layer near the coast and over coastal valleys, scattering out and clearing during the afternoon. Otherwise, dry conditions are expected into early next week. By Sunday, high temperatures are expected to have warmed to the 90s in most areas, 100-105 over the Antelope Valley, and the 70s near the coast. Another couple of degrees of warming is expected going into Monday. Gusty southwest to northwest winds are expected each afternoon over interior areas, and strongest -- upwards of 35-45 mph -- over the Interstate-5 corridor as well as the Antelope Valley and nearby foothills. However, the issuance of Wind Advisories is currently unlikely. .LONG TERM (TUE-FRI)...28/232 PM. Dangerously hot conditions are expected to develop over the region next week, as an upper-level anticyclone builds offshore and expands eastward over California. The latest multi-model consensus offers increasing confidence for 500-mb heights rising to 596-600 dam just north or northeast of the area by late next week. This should correspond to daily high temperatures up to 100 to 105 possible in many areas away from the coast, with highs upwards of 105 to 115 possible over interior valleys and foothills including the Antelope Valley, each day starting Tuesday. Warm overnight low temperatures, especially late next week, will worsen the effects of extreme heat. Nighttime temperatures may not fall below 80 degrees late next week over the interior valleys and nearby foothills. An Excessive Heat Watch has been issued for a large portion of the interior areas from Tuesday morning through Saturday, July 6. In addition, very warm to hot conditions will have the potential to bring significant heat impacts to the coast, starting on Wednesday and continuing through the remainder of next week. This would occur as the marine layer becomes increasingly shallow and retreats toward the coast provided the rising heights aloft. Heat headlines may need to be expanded to include a larger portion of Southern California in later forecasts. Present indications are that precipitation chances will be unlikely (below 20%) through late next week. However, given how hot and strongly mixed the boundary layer will be over interior sections during latter parts of the week, any low-predictability monsoonal moisture influx south of the midlevel ridge axis could introduce chances for showers or thunderstorms over higher terrain. Chances are too low for mention in the forecast at this time, though this scenario will continue to be monitored. && .AVIATION...28/1653Z. At 16Z at KLAX, the marine layer was 2200 feet deep. The top of the inversion was at 4500 feet with a temperature of 22 Celsius. Moderate confidence in all sites becoming VFR today by 19Z. High confidence in VFR conditions through Saturday at KWJF KPMD. There is a chance of ceilings at KPRB (20%) KSBA (50%) KBUR (60%) KVNY (40%) tonight into Saturday. All other sites, high confidence in ceilings. Moderate confidence in any ceilings tonight being in similar categories as last night (persistence). KLAX...Moderate confidence in VFR conditions through at least 04Z. Moderate confidence on MVFR ceilings occurring tonight. Low confidence on timing with ceilings starting as early 06Z and as late 14Z. High confidence in any southeast winds staying under 06 knots. KBUR...High confidence in VFR conditions through at least 04Z. There is a 60% of BKN008-012 ceilings forming tonight as early as 08Z and as last as 14Z. High confidence in seasonal winds. && .MARINE...28/220 PM. The moderate threat of dense fog (visibilities one mile or less) returning tonight along the Central Coast. Moderate confidence that visibilities will be up everywhere else. Moderate confidence the Small Craft Advisories (SCA) winds and/or steep seas will continue through most of tonight from the Central Coast to San Miguel Island. This will be a low-end event however, and conditions may stay just under criteria, but it will still be unpleasant out there. Elsewhere, high confidence in fairly benign conditions through at least Saturday. High confidence in northwest winds increasing once again later Saturday Night and lasting through Monday Night. There is a moderate threat for Gales for the offshore waters from the Central Coast to Point Conception Sunday through Monday. There is also a low but present threat of these winds pushing deep enough into the Santa Barbara Channel to need a Small Craft Advisory. There is a potential for winds to be stronger than the most recent event. As a result of these winds, choppy seas should be expected everywhere. Moderate confidence for significantly and abnormally light winds Tuesday and Wednesday. && .LOX WATCHES/WARNINGS/ADVISORIES... CA...Excessive Heat Watch in effect from Tuesday morning through late Friday night for zones 38-88-343>345-353-376>379-381>383. (See LAXNPWLOX). PZ...Small Craft Advisory in effect until 3 AM PDT Saturday for zones 670-673-676. (See LAXMWWLOX). && $$ PUBLIC...Cohen AVIATION...Kittell MARINE...RK SYNOPSIS...Cohen weather.gov/losangeles Experimental Graphical Hazardous Weather Outlook at: https://www.weather.gov/erh/ghwo?wfo=lox