Point Piedras Blancas to Point Sal out 10 NM Marine Forecast
|Tonight...Nw Winds 10 To 15 Kt In The Evening, Becoming 5 To 10 Kt. Wind Waves 2 Ft Or Less. Nw Swell 3 Ft At 9 Seconds, Building To 4 To 5 Ft At 9 Seconds After Midnight. Patchy Fog After Midnight.|
|Tue...Winds Variable 10 Kt Or Less, Becoming Nw 10 To 15 Kt In The Afternoon. Wind Waves 2 Ft Or Less. Nw Swell 4 To 5 Ft At 8 Seconds. Patchy Fog In The Morning.|
|Tue Night...Nw Winds 10 To 15 Kt In The Evening, Becoming 5 To 10 Kt. Wind Waves 2 Ft Or Less. Nw Swell 4 To 6 Ft At 10 Seconds. Patchy Fog After Midnight.|
|Wed...Nw Winds 5 To 10 Kt. Wind Waves 2 Ft Or Less. Nw Swell 5 To 7 Ft At 10 Seconds. Patchy Fog In The Morning.|
|Wed Night...Nw Winds 10 To 15 Kt In The Evening, Becoming Variable 10 Kt Or Less. Wind Waves 2 Ft Or Less. Nw Swell 6 To 7 Ft At 11 Seconds.|
|Thu...Winds Variable 10 Kt Or Less, Becoming Sw 10 Kt In The Afternoon. Wind Waves 2 Ft Or Less. Nw Swell 7 To 9 Ft At 12 Seconds.|
|Thu Night...Sw Winds 10 Kt In The Evening, Becoming Variable 10 Kt Or Less. Wind Waves 2 Ft Or Less. Nw Swell 7 To 9 Ft At 12 Seconds.|
|Fri...S Winds 5 To 10 Kt. Wind Waves 2 Ft Or Less. Nw Swell 6 To 8 Ft. Patchy Fog.|
|Sat...Nw Winds 10 To 15 Kt. Wind Waves 2 Ft Or Less. Nw Swell 4 To 5 Ft. Patchy Fog.|
| Area Forecast Discussion|
...UPDATED National Weather Service Los Angeles/Oxnard CA
1128pm PDT Monday Oct 19 2020
Very quiet weather is expected through this coming week, except for gusty north winds along the Santa Barbara South Coast and in the Los Angeles mountains. Overnight through morning low clouds will affect coastal areas, and temperatures will drop to below normal by Thursday or Friday. There is a slight chance of light rain this weekend, mainly for Los Angeles County.
.SHORT TERM (MON-THU)...19/804 PM.
Satellite channel difference images show extensive low clouds over the coastal waters this evening, with low clouds making healthy inroads over most coastal areas. The exception is the western Santa Barbara South Coast, where gusty north winds between 25 to 30 mph are keeping the area west of Goleta clear. Weak north winds currently blowing through the I-5 Corridor will strengthen overnight, with gusts to 25 mph and locally up to 30 mph.
Later tonight, expect to see winds over the Los Angeles Mountains shift to the northeast and filling into the Santa Clarita Valley. Although speeds will be weak and around 10-20 mph, this should be enough to cause warming and drying for interior portions of LA County. Elevated fire weather concerns are expected due to this trend, in combination with critically dry fuels in place in these area. The offshore flow will also help keep the low clouds somewhat closer to the coast than last night, with no clouds expected for the Santa Ynez Valley, and only limited portions of the Ventura and LA Coastal valleys.
***From Previous Discussion***
A slight cooling trend is expected to begin on Wednesday, with additional cooling on Thursday due to increasing onshore flow and marine layer depth as well as lowering heights. By Thursday morning, the marine layer depth could be around 2500 feet with low clouds surging into all of the valleys and possibly the lower coastal slopes.
Long Term - Friday through Monday
The broad upper level trough is expected to deepen across the Great Basin on Friday leading to increased onshore flow across Southwest California. The marine layer depth is expected to deepen to between 3000 and 4000 feet on Friday, bringing the potential for morning drizzle and slow to no clearing across portions of the forecast areas. The cooling trend will continue across all areas on Friday, with inland temperatures falling into the 70s.
By the weekend, the broad upper trough continues to dig southeastward across the Great Basin while a weak upper low develops off the coast of Southwest California. Cross sections showing an even deeper moist layer of 4000 to 5000 feet over the weekend. With weak lift and a southerly low level flow, there is a slight chance of measurable light rain, mainly south of Point Conception. At this point, thinking that the best probability is for rainfall amounts to generally remain under 0.10 inches, however, there could be some isolated totals up to 0.25 inches across the coastal slopes and foothills of LA county where there will be enhanced cyclonic flow.
In the wake of the upper level trough passing to our east, there is increasing confidence of a Santa Ana wind event for Monday/Tuesday of next week. The 12z ECMWF (European Centre for Medium-Range Weather Forecasts) model remains consistent showing a LAX-DAG gradient of -3.5 to -4 mb for both Monday and Tuesday, along with some descent upper level wind support and cold air advection. While this event is still a week away, the 12z EC/GFS model and the EC ensembles show the potential for a moderate Santa Ana wind event for Monday/Tuesday with the potential for some very low humidities. Keep following the forecast discussions to see how this potential situation develops.
Low-end Small Craft Advisory (SCA) winds will continue through late tonight from Point Conception to San Nicolas Island, then weaken before likely returning in a very similar way Tuesday night. An additional SCA (Small Craft Advisory) will likely be issued. The winds will become confined to the northwest portion off the Central Coast on Wednesday and Thursday, with a 20 percent chance of touch Gale Force. Short period northwest to west swell will be on the rise through mid-week.
.LOX WATCHES/WARNINGS/ADVISORIES... CA...NONE. PZ...Small Craft Advisory in effect until 3am PDT Tuesday for zones 673-676. (See LAXMWWLOX).
.HAZARD POTENTIAL OUTLOOK (THU-MON).
A moderate Santa Ana wind could bring elevated to brief critical fire weather conditions to Los Angles and Ventura counties by next Monday.