07/258 AM.
A warming trend will continue through Sunday, then a weak to moderate storm system will move into the region and bring cooler temperatures and a chance of precipitation between Tuesday night and Wednesday night. A warming trend is possible for late next week, then a cool, wet, and unsettled weather pattern looks to resume for next weekend into the third week of the month.
(tdy-Mon), 07/252 AM.
The latest satellite imagery shows an upper-level trough of low pressure now sitting well south of the area, near 30N and 120W, off the Baja California coast. Offshore flow is starting to develop as an upper-level ridge builds into the San Francisco Bay area. A warming trend will develop across the region through the weekend. The latest pressure gradients indicate offshore flow starting to reestablish and will likely turn negative later this morning. Temperatures will be well above normal for this time of year with 70s to lower 80s common across the coast and valleys today. Additional warming will take place into Sunday as 500 mb heights climb to near 581 decameters across the Southland.
The winds will be tricky due to the north-northeasterly direction and the lack of upper-level support. Being less of a "true" Santa Ana, the north-northeast direction is a little less typical, but there is a low chance that advisory level winds could develop during the night through morning hours over the weekend in areas, such as through the Interstate 5 Corridor and into the northern portion of the San Fernando Valley. There is a low-to-moderate chance that advisory level Sundowner winds could develop across southern Santa Barbara County the next several evenings, but the wind vectors are a bit out of the alignment to make advisory level winds a slam dunk. The direction of wind support would favor the Montecito Hills area, while the speed support would favor the Gaviota area. This will need to be monitored closely over the next several days.
Cyclonic flow will start to develop on Monday evening as an upper-level trough to the south of the tip of the Aleutian Islands moves into the California coast while cutting off from the flow. Onshore flow should develop, along with a rapidly developing marine layer setting up a cooling trend for Tuesday.
(Tue-Fri), 07/255 AM.
The pattern change will get underway on Tuesday as cooling trend will become more significant. Confidence is high with the temperatures trends, but the trough's cutoff nature is adding uncertainty for the chance of precipitation. EPS and AIEPS solutions suggest a majority of solutions with light to moderate rainfall for the area Tuesday night and into Wednesday night, but the AIGEFS takes a drier stance. There is a high to likely chance of rain at some point between Tuesday night and Wednesday night, but there is a low-to-moderate chance of little to no rain.
A warming trend should develop for Thursday and Friday, but there is still quite a bit of spread across the solutions. Temperature means lean into a warming trend, but the spread of values increase during this period.
The forecast ensembles do lean more into the duo of storm systems for next weekend and into the third week of February. All but a few solutions of the GEFS, EPS, CMC, AIEPS, and AIGEFS have rain for the period. EPS solutions are starting to lean wetter with lower snow levels with 850 mb temperature means dropping to near 0 degrees Celsius over next weekend. EPS solutions have a decent amount of solutions with accumulating snow for KGXA, K3A6, and KSDB with AI-based solutions favoring higher chances and amounts of accumulating snow at this point. Stay tuned as this period could be the more impactful time period for weather across southern California.
07/1126z.
At 1017Z at KLAX, there was no marine layer nor inversion.
VFR TAFs expected at all sites except KPRB, where VLIFR to IFR conds are likely through 18-20Z. There is a 10-20% chance for remaining coastal/valley sites to briefly see IFR-MVFR conds through 18Z. Highest for KSBA, KOXR, KSMO, KLAX, and KLGB.
KLAX, High confidence in TAF. 20% chance for 007-015 cigs through 18Z. No significant east wind component expected.
KBUR, High confidence in VFR TAF. 10% chance for 005-012 cigs through 18Z.
07/225 AM.
Hazardous marine conditions are likely to continue through much of next week.
A long period west swell is impacting the region, with seas of 10-14 feet across the inner waters along the Central Coast and the outer waters from Point Piedras south to San Nicolas Island. Seas will start to decrease through tonight to below 10 feet, but northwest winds will increase through today. Small Craft Advisory (SCA) winds in the 20-30 knots range will be common across the Outer Waters and along the Central Coast into at least early next week. Localized low end Gale Force winds may occur in the afternoon and evening hours today and Sunday from Point Conception south to San Nicolas Island and west through the Outer Waters. There is a 30-50% chance for a Gale Warning to be needed during this timeframe, highest chances Sunday.
West to northwest winds will make their way into the waters south of Point Conception in the afternoon and evening today and Sunday, generally remaining below SCA levels, but local gusts to 25 knots are possible across portions of the San Pedro Channel and near Point Dume. Additionally, offshore flow from the north to northeast will bring 15-25 knot winds to nearshore areas from Ventura to Santa Monica this evening into Monday afternoon, with strongest winds likely along the Malibu Coast late tonight through Sunday early afternoon.
Large swell will continue to create hazardous large breaking waves near the coasts through tonight, and small vessels should avoid these areas. Ventura Harbor may see breaking waves of 12 feet through early this afternoon. Choppier seas will develop this afternoon as winds strengthen.
07/104 AM.
A long period west swell will continue to bring high surf to Southwest California, focused across west facing beaches through late tonight. Elevated surf will likely continue through next week.
Refer to the SRFLOX and CFWLOX products for more details on the current High Surf Advisories.
Ca, High Surf Advisory in effect until 9 PM PST this evening for zones 340-346-349-350. (See LAXCFWLOX). High Surf Advisory in effect until 3 AM PST Sunday for zones 354-362-366. (See LAXCFWLOX). PZ, Small Craft Advisory in effect until 3 AM PST Monday for zones 645-670-673-676. (See LAXMWWLOX).
