Cooler and drier weather will continue for inland areas this week with high temperatures as much as 4 to 8 degrees below averge for inland areas through Thursday. Lowest daytime relative humidity for the deserts will fall to 10 to 15 percent through Thursday. Southwest to west winds during the afternoon and early evening through Thursday will gust to 25 to 35 mph with near critical fire weather conditions on the desert slopes of the mountains. Warmer and more humid for the Labor Day weekend. Mid and higher level tropical moisture could interact with a trough of low pressure near the California coast to bring some showers and a slight chance of thunderstorms during the weekend.
For extreme southwestern California including Orange, San Diego, western Riverside and southwestern San Bernardino counties,
, UPDATED AVIATION DISCUSSION,
(today through Thursday), Cooler and drier weather will continue for inland areas through Thursday with high temperatures as much as 4 to 8 degrees below average. High temperatures will range from the mid to upper 70s near the coast to the mid 80s to lower 90s for the Inland Empire with the lower deserts around 100. Night and morning low clouds will be patchy, but may extend inland into portions of the western valleys at times.
(Friday through Monday), Similar to the track density forecasts immediately pre-development for what became Hurricane Karina, ensemble members of the GFS and Canadian models have once again been the northern and eastern outliers with the track of newly-formed Tropical Storm Marie.
The two Google AI ensembles and the EC AI ensemble are once again farther to the south and west with the core of the greater track density, moving Marie toward the west-northwest toward 22N/123W, then on a track toward the west along 22N, with only a few ensemble members deviating to the north of the core of greater track density. The 00Z GEFS has shown a substantial shift to the south and west with the greater track density toward those other ensembles, though with a smaller number of ensemble members still tracking across northern Baja.
The most likely scenario for southern California from the current guidance would be for some mid and high level moisture from a strengthening Hurricane Marie, well to the southwest of the area, to be drawn northeastward across southern California into the Great Basin by the low pressure system off the West Coast. This would bring a chance of showers and a slight chance of thunderstorms.
Over the next day or so, there should be some narrowing in the spread of potential solutions across southern California as there is better model initialization of the area around strengthening Tropical Storm Marie as well as some improvement in the forecast of the low pressure system just off the West Coast.
011130z, Coasts/Valleys, Areas of low clouds based 1000-1500 feet MSL will give intermittent cigs through 16Z, but more likely around KSNA. Low clouds based around 1000 feet MSL will be patchy after 06Z with less chance and less coverage of cigs tonight into Wednesday morning.
.Mountains/Deserts, Mostly clear skies today and tonight. Breezy westerly winds mainly through mountain passes and desert slopes through 22-07Z. Gusts 25-40 kts with pockets of moderate up/downdrafts over and in lee of ridges.
No hazardous marine conditions are expected through Saturday. Wind gusts around 20 knots are expected each afternoon and evening through Thursday in the vicinity of San Clemente Island.
Southerly swells from tropical cyclones will continue this week. There is a chance of a swell capable of producing high surf arriving this weekend, however confidence on surf size and timing is rather low today. Stay tuned as details become clearer in coming days.
Ca, None. PZ, None.