31/1258 PM.
Cool and cloud conditions with periods of light rain will continue through tonight. Gusty north to northeast winds are favored Wednesday night through Saturday with a moderate Santa Ana event possible Friday and Saturday. Much warmer temperatures with mostly sunny skies are expected this weekend.
(Tue-Fri), 31/815 PM.
Latest satellite and surface observations indicate cloudy skies across the area as a plume of moisture is moving overhead. Looking at radar and rain gauges, some light rain has fallen with amounts under 0.10 inches from San Luis Obispo county down to Ventura county. Some southwesterly winds, gusting 25-35 MPH, are currently observed across the mountains.
For tonight/Wednesday, the moisture plume will continue to stream across the area, keeping skies in the partly to mostly cloudy range. There will continue to be a threat of light rain through Wednesday, but amounts, if any, are expected to remain quite light (generally under 0.10 inches). Some upslope areas could get a little more (around 0.25 inches), but those amounts would be isolated. Gusty southwesterly winds will continue through Wednesday across interior sections (mountains and Antelope Valley). With the cloud cover and moderate onshore gradients, highs on Wednesday will remain on the cool side, generally in the 60s with some 50s across the mountains.
By Wednesday night, models and WPC guidance indicate rain chances diminish below 15 percent. So, main concern for Wednesday night through Friday will be winds. For Wednesday night through Thursday night, northerly winds will be on the increase across the area. Deterministic models indicate a nice bump up in northerly offshore gradients. Looking at the latest REFS solutions, there is at least a 60-80% chance of winds greater than 35-40 MPH across the I-5 Corridor and the Santa Barbara county mountains. So, there is a high likelihood of needing wind advisories in those areas Thursday and Thursday night. By late Thursday night and Friday, the flow shifts to the northeast and a moderate to locally strong Santa Ana wind event is expected to develop. Moderate offshore pressure gradients are forecast by the high resolution models. Looking at ensembles, there is at least a 60-80% chance of northeast winds greater than 40 MPH across the usual Santa Ana wind-prone areas of Ventura/LA counties. The ensemble meteogram for Camarillo indicates mead wind gusts of 43 MPH on Friday, supporting the idea of a widespread moderate offshore event with some possibilty of warning-level gusts in the more favored areas. So, further wind advisories will likely be needed Thursday night and Friday with a chance of some warnings also.
With the developing offshore flow, temperatures will be on the upswing through the period. By Friday, afternoon high temperatures are forecast to be in the 70s to lower 80s across the area. As for cloud cover, partly to mostly cloudy conditions will continue through Wednesday evening. For Thursday through Friday, skies will be mostly clear.
(Sat-Tue), 31/1256 PM.
Ridging and weak to moderate offshore flow will continue through the weekend with advisory level winds potentially continuing for Santa Ana prone areas into Saturday. Temperatures will respond with about 6 degrees of warming on Saturday and another 1 to 2 degrees on Sunday. Max temps will be 6 to 12 degrees above normal both days with highs in the 80s to near 90 across the csts and vlys.
The ridge breaks down early next week. Onshore flow returns as well and this will bring 3 to 6 degrees of cooling to most areas. Max temps, however, will remain above normal.
Both the AI-GFS and AI-EC show no significant rain in the day 8 to 14 outlook period and favored continued above normal temperatures.
01/0137z.
At 2223Z over KLAX, the marine layer was 4000 ft deep. The top of the inversion was at 5200 feet with a temperature of 13 C.
Overall, moderate confidence in 00Z TAF Package. MVFR to VFR generally expected with a 20-50% chance of -SHRA. Lower confidence showers will affect KPMD, KWJF and KPRB.
KLAX, Moderate confidence in TAF. MVFR CIGs with VFR VSBYs and short-lived -SHRA/VCSH expected. No significant east wind component expected.
KBUR, Moderate confidence in TAF. There is a 20% chc of -RA through 05Z.
31/715 AM.
High confidence in winds and seas staying under Small Craft Advisory (SCA) levels through today. A weak frontal system will move across the coastal waters bringing light showers to the area today and tonight, mostly north of Point Conception. A few light showers could linger into Thursday across the northern waters.
Strong SCA winds with a moderate chance of low-end GALES is expected to develop for the coastal waters south of Point Conception (including nearshore and the Santa Barbara Channel) Wednesday night. These winds will become very widespread Thursday and will last through Friday morning.
Expecting seas to build quickly on Thursday, peaking Thursday night. Seas could reach SCA levels 10-12 feet over the outer waters and inner waters north of Point Sal. Seas for the southern inner waters could peak around 4 to 7 feet. Wave heights should drop off rather quickly as winds shift to the northeast Friday morning.
Ca, NONE. PZ, Small Craft Advisory in effect from 9 AM Thursday to 3 AM PDT Friday for zone 645. (See LAXMWWLOX). Small Craft Advisory in effect from 2 PM Wednesday to 3 AM PDT Friday for zone 650. (See LAXMWWLOX). Small Craft Advisory in effect from 3 AM Thursday to 11 AM PDT Friday for zones 670-673. (See LAXMWWLOX). Small Craft Advisory in effect from 6 PM Wednesday to 11 AM PDT Friday for zone 676. (See LAXMWWLOX).
