07/824 PM.
Benign weather will continue through the weekend with a chance of morning low clouds and fog along the Los Angeles coast. A warming trend will continue this week with well above normal temperatures Monday through next Friday, peaking Tuesday through Thursday. Offshore winds will increase Monday into Tuesday, and are expected to persist through much of the week.
(Sun-Wed), 07/821 PM.
Warming trend started today, with most coastal/valley areas reporting high in the 70s, with few warm spots climbing into the lower to mid 80s. Current satellite imagery showing some low clouds and fog near Catalina Island, with a chance for those low clouds to reach the southern coast of LA county late tonight into Monday morning. Over the next few days, an upper level ridge of high pressure, centered over the Eastern Pacific, will gradually strengthen over the area. At the surface, weak to moderate offshore gradients will prevail. As of 7 pm this evening, the LAX- Daggett gradient was -2.4 mb while LAX-Bakersfield was -6 mb.
Forecast-wise, two main issues will be offshore winds and temperatures. With respect to offshore winds, the offshore pressure gradients will help generate some weak to locally moderate north to northeast winds across typical wind prone areas of Ventura/LA counties, as well as gusty offshore winds across wind prone foothills and canyons of San Luis Obispo and Santa Barbara counties. Offshore gradients to the north and east are expected to peak on Tuesday morning, but throughout the short term period, the upper level support remains rather weak. So, do not anticipate any widespread advisory level winds through Tuesday but a 30-40% chance of some advisories being needed for the Santa Susana mountains.
As for temperatures, the combination of the upper level ridge strengthening and the offshore surface pressure gradients, a nice warming trend will continue. By Tuesday and Wednesday, most areas will be 10-15 degrees above normal with widespread 80+ degree temperatures across the valleys and inland coastal plain. No record-breaking temperatures are expected, but it will be rather warm. As for overnight lows, it will be chilly in wind sheltered areas.
(Thu-Sun), 07/1258 PM.
Overall, the 12Z models have the same broad idea, but differ in the details. However, the differences will have minimal impact on the overall sensible weather.
Through the period, the upper level ridge is forecast to weaken. At the surface, the offshore flow will weaken with weak diurnal flow expected by the weekend. So, will anticipate a slight and gradual cool down through the period with a decrease in northeasterly winds. By the weekend, there is a decent chance that the marine layer stratus/fog will return to the coastal plain. Overall, just rather benign weather through next week.
07/2324z.
At 2325Z at KLAX, the marine layer was 500 feet deep. The top of the inversion was 1700 feet with a temperature of 20 C.
Moderate confidence in KSBA, KOXR, KSMO, KLAX, and KLGB after 07Z Monday, due to uncertainty in potential arrival of low cigs. otherwise high confidence for all TAFs. There is a 30% chance of conds remaining VFR through the period at KLAX. There is a 30% chance of VLIFR to LIFR conds at the specified aforementioned sites, with conds potentially arriving as early as 06Z Mon for KSMO, KLAX, and KLGB and around 09Z for KOXR and KSBA.
KLAX, Good confidence in TAF. There is a 30% chance of VFR conds persisting through the period, otherwise LIFR-IFR conds will likely arrive after 07z Mon. Any easterly winds will remain less than 7 knots.
KBUR, High confidence in VFR TAF.
07/839 PM.
For the outer waters, there is a 40-60% chance of low-end Small Craft Advisory (SCA) conditions through the week, especially across the western portions of the waters north of Santa Cruz Island during the afternoon and evening hours.
For the inner waters including the southern California bight and the nearshore waters along the Central Coast, there is a 30-50% of local northeast SCA level wind gusts from Ventura to Santa Monica as well as from Pismo Beach to Point Piedras Blancas each night and morning through Tuesday, and a 30% chance of reoccurring on Wednesday. Otherwise, winds and seas should remain below SCA levels.
There is a moderate chance of dense fog over the coastal waters through Monday morning. Confidence remains low on timing and coverage.
Ca, NONE. PZ, Small Craft Advisory in effect until 3 AM PST Tuesday for zones 670-673. (See LAXMWWLOX).
