Point Sal to Santa Cruz Island CA including San Miguel and Santa Rosa Islands Marine Forecast
15 - 25
10 - 15
15 - 25
10 - 20
20 - 30
10 - 15
|Tonight...Sw Winds 15 To 25 Kt In The Evening, Becoming W 10 To 20 Kt. Combined Seas 6 To 8 Ft Dominant Period 11 Seconds. Rain.|
|Wed...W Winds 10 To 15 Kt, Becoming Sw 10 To 20 Kt With Local Gusts To 25 Kt In The Afternoon. Wind Waves 2 To 4 Ft. Nw Swell 6 To 8 Ft At 12 Seconds, Building To 8 To 10 Ft At 13 Seconds In The Afternoon. A Slight Chance Of Rain In The Morning, Then A Chance Of Showers And A Slight Chance Of Tstms.|
|Wed Night...W Winds 15 To 25 Kt With Gusts To 30 Kt In The Evening, Becoming Sw 10 To 20 Kt. Combined Seas 10 To 12 Ft Dominant Period 13 Seconds. Showers And A Slight Chance Of Tstms.|
|Thu...Nw Winds 10 To 20 Kt With Gusts To 25 Kt. Wind Waves 2 To 4 Ft. Nw Swell 9 To 10 Ft At 11 Seconds. A Chance Of Rain And A Slight Chance Of Tstms In The Morning.|
|Thu Night...Nw Winds 20 To 30 Kt In The Evening, Becoming 10 To 20 Kt With Gusts To 25 Kt. Combined Seas 10 To 11 Ft Dominant Period 11 Seconds, Subsiding To 5 To 7 Ft Dominant Period 11 Seconds After Midnight.|
|Fri...Nw Winds 10 To 15 Kt. Wind Waves 2 Ft Or Less. Nw Swell 4 To 6 Ft At 11 Seconds.|
|Fri Night...Nw Winds 10 To 20 Kt With Gusts To 25 Kt. Wind Waves 2 To 4 Ft. Nw Swell 3 To 4 Ft At 11 Seconds.|
|Sat...Nw Winds 15 To 25 Kt. Combined Seas 4 To 5 Ft.|
|Sun...Nw Winds 15 To 25 Kt. Combined Seas 4 To 6 Ft. Winds And Seas Higher In And Near Tstms.|
| Area Forecast Discussion|
National Weather Service Los Angeles/Oxnard CA
853pm PDT Tuesday Mar 28 2023
Rain and mountain snow will spread into the region through tonight as a storm system originating from the Gulf of Alaska digs into the region. A showery and unsettled weather pattern will linger for Wednesday and Thursday. Dry but cool conditions are expected for Friday through the weekend.
Short Term - Tuesday through Friday
Latest satellite continues to spin off the northern CA coast this evening with a cold front, moving across the low, entering the forecast area this evening. Current radar and surface observations indicate light to locally moderate rain moving across San Luis Obispo and Santa Barbara counties. Rainfall totals, so far, through early this evening are generally between 0.10 and 0.50 inches with local amounts up to 0.75 inches across the foothills of San Luis Obispo county. Rain rates have been less than 0.25 inches per hour.
Forecast-wise for the immediate short term, the main story will be the cold front. This front will continue to sweep south and east across the area overnight, bringing light to moderate rainfall to the area as well as some mountain snow. Rain and snow amount thinking from previous shift still looks on track (check out discussion below). Southerly winds are increasing ahead of the cold front with gusts 35-50 MPH currently reported across San Luis Obispo and Santa Barbara counties. Expect this winds to continue through tonight and current slate of WIND ADVISORIES will remain in effect.
Overall, current forecast has good handle on the immediate short term with regard to the front and the associated precipitation and wind. So, no significant updates are expected at this time.
***From Previous Discussion***
An upper low continues to spin just west of the coast near the CA/OR border. Racing out ahead of it is a fast moving cold front that will sweep through the area tonight into early Wednesday. Forecast for this storm remains largely unchanged. There will be a 6-8 hour period of light to perhaps briefly moderate rain, mostly overnight tonight but lasting into the morning hours in LA County. Hi res ensembles continue to advertise rain rates mostly around a tenth of an inch per hour, but locally up to a quarter inch in the foothills and mountains. The mean wind speeds in the lower levels aren't particularly strong, topping out around 25-30kt from the southwest so the upslope enhancement won't be as strong as earlier storms this winter and likely favoring the Santa Lucias the most. Rain amounts during this part of the storm are expected to be around a half inch at lower elevations and up to an inch or so in the foothills and mountains. Snow levels will be around 6000', possibly lowering to 5000' at the very back edge early Wednesday.
Winds are starting to pick up ahead of the front, especially across interior SLO County and wind advisories are in effect there through tonight.
Following the frontal passage tonight into early Wednesday there will be at least a few hours of little to no rain and likely even some sunshine (especially south of Pt Conception) before the colder and more unstable part of the system arrives later Wednesday into Thursday. Models show a favorably positioned 130kt jet across southern LA County along with rapidly cooling temperatures aloft that will increase lapse rates. CAPE values aren't particularly impressive but the other factors are strong enough to warrant at least a slight chance of thunderstorms through early Thursday. Precip will be much more showery during this phase of the storm so amounts will be highly variable but overall another half inch or so is expected on average with locally higher amounts in thunderstorms, where rain rates could briefly reach a half inch per hour. Also can't rule out waterspouts over the ocean and small tornadoes over land given the favorable position of the jet and upper low
Showers and storms expected to taper off Thursday with dry but cool weather Friday. Deterministic models show a secondary trough coming through the area, though model clusters suggest it will be weaker than what the GFS/ECMWF (European Centre for Medium-Range Weather Forecasts) are indicating. And in any case none of the ensembles show any rain with it so mainly just continued below normal temperatures.
Long Term - Saturday through Tuesday
Air mass warms Sat/Sunday as heigheights rise. In addition, weakening onshore flow, even going slightly offshore to the north will generate additional warming at the surface that should bring highs to the lower 70s in some areas both days.
A weak trough and increasing onshore flow return Monday/Tuesday which at the very least will result in some cooling area-wide. There are a few ensemble solutions that show some light precip later Monday into Tuesday, justifying the small rain chances across parts of the area, however, it's more likely that rain will stay north of the area. The remainder of next week looks dry at this point.
Ahead of a cold front, a period of Small Craft Advisory (SCA) level S-SW winds is expected to move from NW to S across the waters through tonight into tomorrow morning. There is a 40-50% chance of SCA (Small Craft Advisory) level SW-W winds in the SBA Channel tonight, and sub- advisory S-SE winds up to 20 kts into early Wednesday morning for the waters adjacent to L.A. County.
SCA (Small Craft Advisory) level SW-W winds are likely in the southern two outer waters zones Wednesday night, with a 30-40% chance of SCA (Small Craft Advisory) level winds elsewhere. However, seas may reach SCA (Small Craft Advisory) levels in the northern outer waters and northern inner waters zones Wednesday night into early Thu anyway.
A period of SCA (Small Craft Advisory) level W-NW winds is likely across the entire waters Thu night, except just a 40% chance in the southern inner waters. At this time, SCA (Small Craft Advisory) conds are not expected across the waters Fri thru Sat.
There is a slight chance of thunderstorms across the waters Wed thru Thu morning. Some storms could produce small hail, gusty winds, dangerous lightning, and possibly waterspouts.
Large swell in the coastal waters may bring marginal high surf 8 to 12 feet on Central Coast beaches on Wednesday and Thursday and 4 to 7 feet on Ventura beaches on Thursday. This is a fairly low confidence forecast with only a 50 percent chance of reaching criteria. However, there will be a high risk of rip currents on many beaches Wednesday and Thursday.
NOAA Los Angeles/Oxnard CA Office: Watches - Warnings - Advisories
CA...Wind Advisory in effect until 5am PDT Wednesday for zones 38-342-344-345.
High Surf Advisory in effect from 11am Wednesday to 8am PDT Thursday for zones 340-346. (See LAXCFWLOX). Winter Weather Advisory in effect from 2am Wednesday to 10 am PDT Thursday for zones 353-376-377. (See LAXWSWLOX). High Surf Advisory in effect from 8pm Wednesday to 8pm PDT Thursday for zone 354. (See LAXCFWLOX). Winter Weather Advisory in effect from 5am Wednesday to 2 PM PDT Thursday for zone 378. (See LAXWSWLOX). Winter Weather Advisory in effect from 4am Wednesday to 2 PM PDT Thursday for zone 379. (See LAXWSWLOX). Winter Storm Warning in effect from 4am Wednesday to 2 PM PDT Thursday for zone 380. (See LAXWSWLOX). Wind Advisory in effect from noon Wednesday to 6am PDT Thursday for zones 381>383.
PZ...Small Craft Advisory in effect until 3am PDT Wednesday for zones 645-670-673-676.