Point Mugu to San Mateo Point CA including Santa Catalina and Anacapa Islands Marine Forecast
|Tonight...Western Portion, Nw Winds 15 To 25 Kt Becoming N 5 To 10 Kt After Midnight. Elsewhere, Sw Winds 5 To 10 Kt Becoming E After Midnight. Combined Seas 4 To 6 Ft Dominant Period 7 Seconds. Patchy Fog After Midnight.|
|Sun...Winds Variable 10 Kt Or Less, Becoming Sw 10 Kt In The Afternoon. Wind Waves 2 Ft Or Less. W Swell 3 Ft At 10 Seconds. Patchy Fog In The Morning.|
|Sun Night...Sw Winds 5 To 10 Kt. Wind Waves 2 Ft Or Less. W Swell 2 To 3 Ft At 12 Seconds. Chance Of Rain After Midnight.|
|Mon...S Winds 15 To 20 Kt, Becoming Sw 15 To 25 Kt With Gusts To 30 Kt In The Afternoon. Combined Seas 3 To 5 Ft Dominant Period 11 Seconds, Building To 5 To 6 Ft Dominant Period 18 Seconds In The Afternoon. Rain Likely In The Morning, Then Rain.|
|Mon Night...Nw Winds 15 To 25 Kt With Gusts To 30 Kt. Combined Seas 6 To 8 Ft Dominant Period 17 Seconds. Slight Chance Of Rain In The Evening.|
|Tue...Nw Winds 15 To 20 Kt With Gusts To 25 Kt, Becoming 10 To 15 Kt In The Afternoon. Wind Waves 2 To 4 Ft. W Swell 5 To 7 Ft.|
|Tue Night...Nw Winds 10 To 15 Kt. Wind Waves 2 Ft Or Less. W Swell 4 To 6 Ft.|
|Wed...Nw Winds 5 To 10 Kt. Wind Waves 2 Ft Or Less. W Swell 3 To 5 Ft.|
|Thu...Nw Winds 5 To 10 Kt. Wind Waves 2 Ft Or Less. W Swell 3 To 4 Ft.|
| 209 PM PDT Sat Oct 23 2021 |
Synopsis for the southern California coast and Santa Barbara Channel including the Channel Islands National Marine Sanctuary and National Park - PZZ600
at 21Z, or 2 PM PDT, a 1019 surface high was located 500 NM SW of Point Conception, and a 975 MB surface low was 400 NM west of British Columbia, with a cold front extended southward to California. A strong storm is expected Sunday night into Monday, which will bring gusty south winds, steep, short-period waves, and a large northwest to west swell.
| Area Forecast Discussion|
National Weather Service Los Angeles/Oxnard CA
147pm PDT Sat Oct 23 2021
Very quiet weather is expected through Sunday afternoon, with partly to mostly cloudy skies and seasonable temperatures. A Pacific storm system will bring widespread moderate to heavy rain to the area Sunday night and Monday, along with gusty winds and cooler temperatures. Warming and drying are expected the rest of next week.
Short Term - Today through Tuesday
Plenty of stratocu lingered early this afternoon over the coast, vlys and cstl slopes of VTU/L.A. Counties for partly to mostly cloudy skies. Elsewhere, skies were mostly sunny with just a few hi clouds at times. Overall, little change can be expected for the rest of the afternoon. Gusty NW-N winds can be expected this afternoon for southern SBA County, especially W of Goleta, and also along the I-5 corridor in the mtns. Gusty W-SW winds will also prevail across the Antelope Vly. Temps this afternoon will be about 5-10 deg below normal in all areas, with highs in the upper 60s to lower 70s for the warmest vlys and inland coastal areas.
A mostly a zonal flow aloft is expected to persist over the forecast area thru tonight, with H5 heigheights about 574-579 dam from N to S. The flow aloft will turn more to the SW on Sunday as a large upper level trough over the E Pac approaches the CA coast.
There should be partly to mostly cloudy skies over the forecast area tonight thru Sun, including low clouds along the coast and into some of the vlys overnight into Sunday morning. In addition, a warm front associated with a Pacific storm system will approach the Central Coast on Sun, with increasing chances of rain expected mainly over SLO County thru the afternoon. Gusty NW-N winds can be expected this evening for southern SBA County and in the mtns along the I-5 Corridor, likely to Advisory levels for the Santa Ynez mtns and a Wind Advisory will be issued with the afternoon zone package. For Sunday afternoon, winds are expected to switch so SW and become quite gusty by late in the day, especially over SLO County. High temps on Sunday are expected to remain about 5-10 deg below normal across much of the region.
The large eastern Pac upper level trough is forecast to move E to just off the CA coast Sunday night, then move quickly E thru the state Monday and Monday evening. A strong early season storm system associated with this upper level trough will move into SW CA during the period. The main cold front is forecast to push into SLO County late Sunday night or early Mon, into SBA County early to mid Monday morning, and thru VTU/L.A. Counties Monday afternoon and early evening. It looks like moderate to heavy rain will affect SLO County Sunday night, especially across western areas into the Santa Lucia Range. Moderate to occasionally heavy rain will affect SBA County by early Monday morning as well, followed by mainly moderate rain into VTU/L.A. Counties starting mid to late Monday morning. The rain will taper off from NW to SE across the forecast area thru Monday afternoon, with lingering chances of rain mainly over VTU/L.A. Counties into Monday evening.
Snow is not going to be a factor with this weather system as snow levels should remain well above 8000 feet until the tail end of the event Monday evening. In addition, the coldest air and most unstable airmass with this storm will remain over northern and central CA thru Monday and no thunderstorms are expected for the forecast area.
Strong and gusty S to SW winds ahead of the main front can be expected across the region Sunday night and Mon. Winds may even reach High-end Advisory levels for much of SLO/SBA Counties later Sunday night into Monday morning, and Wind Advisories will likely be needed.
Preliminary rainfall amounts for this storm system from Sunday night into Monday evening continue to be about 1.00-3.00 inches across SLO/SBA Counties, and 0.50-1.50 inches for VTU/L.A. Counties with local higher amounts over 1.75 inches. The highest rainfall totals will be along south and southwest facing slopes, such as the Santa Lucia Range and Santa Ynez Mtns. Recent burn areas will be susceptible to minor mid and debris flows, especially in and around the Alisal burn area in southern Santa Barbara County. Projected rainfall intensities of 0.25 to 0.50 inch per hour with local intensities up to 0.75 inch per hour are below USGS thresholds for more impactful mid and debris flows. However, this situation will be closely monitored for any changes as we draw closer to the event.
As far as temperatures, it will turn even cooler on Monday with the clouds and rain over the region. Highs will be about 7-14 deg below seasonal norms, and only reach into the upper 50s and 60s for the coast and vlys.
The upper level trough will move further to the E later Monday night thru Tue, allowing H5 heigheights to increase to near 583 dam. There will also be rather sharp offshore pressure gradient trends thru the day. Skies will become mostly clear for most areas Monday night with sunny skies on Tue. Temps on Tuesday will be a few degrees warmer than Mon, but highs will still be about 5-10 deg below normal for many areas.
Long Term - Wednesday through Saturday
Upper level ridging will continue.nue to build into southern CA Wednesday and Thu, with H5 heigheights up to around 586 dam. A weak upper level trough should move into the area on Fri, then some upper level ridging should move back in on Sat. Offshore gradients to the N and E are expected Wednesday and Thu, then offshore gradients mainly to the N are forecast for Fri into Sat. Breezy to gusty N to NE winds will be possible mainly night and morning hours in the usual wind-prone areas thru mid week. Mostly clear skies can be expected across the region thru Fri, then some marine layer clouds may develop along coastal areas Fri night into Sat morning with clearing by afternoon. A warming trend is expected during the extended period, with temps increasing to several degrees above normal in most areas by Thu or Fri.
Moderate to high confidence in Small Craft Advisory (SCA) winds 20 to 30 knots continuing for the outer waters through tonight. SCA (Small Craft Advisory) is also in effect for the western portions of the southern inner waters. The winds will generate choppy seas over all waters through at least tonight, with 3 to 5 foot 6 second period waves common. High confidence in a long period swell leading to greater than 10 foot (SCA (Small Craft Advisory) threshold) seas off the Central Coast through Saturday.
A storm system is still on track to impact the area Sunday and Monday. This storm will bring a period of gusty SW winds everywhere, including a 70 percent chance of 6 or so hours of Gale Force Winds north of Point Arguello Sunday Night. This storm will also bring a large swell impacting all areas by Monday and last through Wednesday, peaking Monday afternoon through early Tuesday. During this peak, large breaking waves will pose dangers to boats and divers nearshore, with breaking waves possible over the Morro Bay and Ventura Harbor entrances. The chance of thunderstorms is minimal.
High Surf Advisories are in effect for the Central Coast and Ventura County, with a Beach Hazards Statement for Los Angeles County (which is likely to be borderline High Surf). This is to cover the increasing surf through 10 pm tonight, but also to message the larger more impactful swell and surf for Monday and Tuesday.
Moderate to high confidence in a very large west-northwest swell peaking at 15 to 20 feet with a 17 second period over the Central Coast, with about half those heigheights for the inner waters from Santa Barbara to Orange County. The peak of the swell will be Monday afternoon through early Tuesday morning. A swell this size will result in High Surf Advisories and dangerous currents over nearly all coasts. There is a chance that surf heigheights reach around 20 feet on the Central Coast, which could result in damage to coastal structures like piers. A High Surf Warning will be considered in the coming days.
NOAA Los Angeles/Oxnard CA Office: Watches - Warnings - Advisories
CA...High Surf Advisory in effect until 10pm PDT this evening for zones 34-35-40. (See LAXCFWLOX). Wind Advisory in effect from 8pm this evening to 3am PDT Sunday for zones 39-52.
Beach Hazards Statement in effect until 10pm PDT this evening for zones 41-87. (See LAXCFWLOX). PZ...Small Craft Advisory in effect until 9pm PDT this evening for zones 645-650-655.
Gale Watch in effect from Sunday evening through late Sunday night for zones 645-670-673.
Small Craft Advisory in effect until 3am PDT Sunday for zones 670-673-676.
Hazard Potential Outlook (Tuesday - Saturday)
High surf and dangerous rip currents will affect area beaches Tuesday through Wednesday, largest into Tuesday with potential harbor closures.