Point Piedras Blancas to Point Sal from 10 to 60 NM Marine Forecast
|Tonight...Nw Winds 15 To 25 Kt With Gusts To 30 Kt. Combined Seas 6 To 7 Ft Dominant Period 8 Seconds. Patchy Fog In The Evening, Then Patchy Dense Fog With Vsby 1 Nm Or Less.|
|Sat...Nw Winds 15 To 20 Kt With Gusts To 25 Kt. Strongest Western Portion. Combined Seas 6 To 7 Ft Dominant Period 8 Seconds, Building To 8 Ft Dominant Period 8 Seconds In The Afternoon. Patchy Dense Fog With Vsby 1 Nm Or Less In The Morning.|
|Sat Night...Nw Winds 20 To 30 Kt, Becoming 15 To 20 Kt With Gusts To 25 Kt After Midnight. Combined Seas 6 To 7 Ft Dominant Period 8 Seconds. Patchy Dense Fog With Vsby 1 Nm Or Less After Midnight.|
|Sun...Nw Winds 10 To 20 Kt With Local Gusts To 25 Kt. Wind Waves 2 To 4 Ft. Nw Swell 4 To 6 Ft At 8 Seconds. Patchy Dense Fog With Vsby 1 Nm Or Less In The Morning.|
|Sun Night...Nw Winds 10 To 15 Kt With Gusts To 20 Kt. Wind Waves 1 To 3 Ft. Nw Swell 4 To 5 Ft At 8 Seconds. Patchy Fog After Midnight.|
|Mon...Nw Winds 10 To 15 Kt. Wind Waves 2 Ft Or Less. Nw Swell 3 To 4 Ft At 8 Seconds. Patchy Fog In The Morning.|
|Mon Night...Nw Winds 10 To 15 Kt With Gusts To 20 Kt. Wind Waves 1 To 3 Ft. N Swell 3 Ft At 8 Seconds. S Swell 2 Ft. Patchy Fog After Midnight.|
|Tue...Nw Winds 10 To 15 Kt With Gusts To 20 Kt. Wind Waves 2 To 4 Ft. N Swell 3 To 5 Ft. Patchy Fog.|
|Wed...Nw Winds 10 To 15 Kt With Gusts To 20 Kt. Combined Seas 5 To 6 Ft.|
| Area Forecast Discussion|
...UPDATED National Weather Service Los Angeles/Oxnard CA
444pm PDT Fri September 18 2020
updated aviation discussion
Strengthening onshore flow beneath broad troughing over the West Coast will bring a cooling trend through Monday. Night through morning low clouds and fog will expand into most coastal and lower valley areas by Monday. Gusty northerly winds are expected across southern Santa Barbara County through Saturday morning. A warming trend is possible for the latter half of next week as ridging aloft settles into the region.
.SHORT TERM (TDY-MON)...18/141 PM.
Southwest flow aloft continues over the region this afternoon ahead of broad troughing over the West Coast. Onshore flow continues to strengthen this afternoon. A cooling trend will continue through the weekend and into Monday along with a deepening marine layer. The latest AMDAR soundings from KLAX indicate a marine layer depth closer to 600 feet deep. The marine layer depth should deepen to near 1000 feet deep by Saturday morning, possibly thinning slightly for Sunday morning, then deepening again on Monday. Middle and high level cloudiness from what used to be tropical storm Karina will continue to thin out across the region tonight which should allow for better stratus formation.
With the trough moving over the region, the smoke that has been in place the last couple of weeks will clear out over a majority of the area. Increasing southwest flow in the boundary layer will increase transport winds and the trough should enhance mixing. The smoky skies should continue to improve across the area, except for portions of Los Angeles County where the Bobcat Fire is still actively burning at this time.
A dying boundary north of the region will move south and tighten the northerly pressure gradient through Sunday. Marginally gusty Sundowner winds are already occurring this afternoon and will increase across southern Santa Barbara County later and linger into Saturday morning. A wind advisory remains in effect from 4 pm PDT this afternoon through 9 am PDT Saturday morning. Gusts up to 45 mph are possible, especially west of Goleta out toward the Gaviota area. If traveling across this area, gusty cross winds are possible on Highways 101 and 154 this afternoon and tonight. If planning any outdoor recreational activities this afternoon and evening, such as kayaking out near Gaviota and Refugio, it might be best to delay these activities when these winds may not present hazardous weather and/or sea conditions.
A tricky cloud forecast is on tap for tonight. Cold air advection could make for little marine layer induced stratus south of Point Conception. The previous forecast was scaled back for a later arrival. Little, if any stratus should make into the Ventura County Coast or the Santa Barbara South Coast. Better confidence exists for the Central Coast and the Santa Ynez Valley. Night through morning low clouds and fog should start to expand into Saturday night and Sunday as the eddy circulation should allow for better coverage.
Zonal flow should setup for Sunday between troughs as the trough along the southern Oregon coast lifts out and another trough dips in behind it. The marine influence should continue to win out for the coast and lower valley, keeping a cooling trend going. Less confidence for the mountains and desert as these areas could end warming.
.LONG TERM (TUE-FRI)...18/138 PM.
The influence of the trough should linger into Tuesday and keep cooler temperatures in place. The deepest marine layer of the week should be in place between Monday and Tuesday, then ridging aloft should start to build into the region and thin the marine layer. A warming trend will develop for the latter half of the week. By Thursday or Friday, stratus coverage could be minimal as weak offshore flow develops. For the current time, no gusty offshore winds are expected, but this will need to be monitored closely for development.
Across the outer waters... Small Craft Advisory (SCA) level wind will continue through Saturday night and there is a forty percent chance of it continuing through Sunday night. The strongest winds will be in the afternoon and evening hours. Otherwise, conditions will remain below SCA (Small Craft Advisory) level through the forecast period.
Across the nearshore waters of the Central Coast... There is a forty percent chance of SCA (Small Craft Advisory) level wind during the afternoon and evening hours through Saturday night. Otherwise, conditions will remain below SCA (Small Craft Advisory) level through the forecast period.
Across the inner waters south of Point Conception... SCA (Small Craft Advisory) level wind will continue across the western portion of the Santa Barbara Channel through Saturday night. Otherwise and elsewhere, conditions will remain below SCA (Small Craft Advisory) level through the forecast period.
Patchy fog will continue into next week across the coastal waters. The poorest visibility and most widely spread conditions will occur in the overnight and morning hours.
.LOX WATCHES/WARNINGS/ADVISORIES... CA...Wind Advisory in effect until 9am PDT Saturday for zones 39-52. (See LAXNPWLOX). PZ...Small Craft Advisory in effect until 3am PDT Sunday for zones 650-670-673-676. (See LAXMWWLOX).
.HAZARD POTENTIAL OUTLOOK (MON-FRI).
No significant hazards expected.