Santa Cruz Island to San Clemente Island to 60 NM offshore including San Nicolas and Santa Barbara Islands Marine Forecast
|Tonight...Nw Winds 20 To 25 Kt With Local Gusts To 30 Kt, Becoming 15 To 20 Kt With Gusts To 25 Kt After Midnight. Strongest Nw Of San Nicolas Island. Combined Seas 6 To 8 Ft Dominant Period 9 Seconds.|
|Tue...Nw Winds 10 To 15 Kt, Becoming 10 Kt In The Afternoon. Wind Waves 2 Ft Or Less. Nw Swell 4 To 6 Ft At 12 Seconds.|
|Tue Night...Nw Winds 5 To 10 Kt. Wind Waves 2 Ft Or Less. Nw Swell 3 To 5 Ft At 11 Seconds. Patchy Fog.|
|Wed...Nw Winds 5 To 10 Kt, Becoming W 10 To 15 Kt In The Afternoon. Wind Waves 2 Ft Or Less. W Swell 4 To 6 Ft At 12 Seconds. Patchy Fog In The Morning.|
|Wed Night...Nw Winds 10 To 15 Kt. Wind Waves 2 Ft Or Less. W Swell 6 To 8 Ft At 11 Seconds.|
|Thu...Nw Winds 10 To 15 Kt. Wind Waves 1 To 3 Ft. W Swell 5 To 7 Ft At 12 Seconds. Patchy Fog In The Morning.|
|Thu Night...Nw Winds 15 To 20 Kt With Gusts To 25 Kt. Combined Seas 6 To 8 Ft Dominant Period 13 Seconds. Patchy Fog After Midnight.|
|Fri...Nw Winds 15 To 20 Kt With Gusts To 25 Kt. Combined Seas 7 To 10 Ft. Patchy Fog.|
|Sat...Nw Winds 15 To 20 Kt With Gusts To 25 Kt. Combined Seas 8 To 11 Ft. Patchy Fog.|
| 207 PM PDT Mon Oct 18 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 1020 MB high was located 500 NM W of Point Conception. Gusty northwest winds will continue through tonight.
| Area Forecast Discussion|
National Weather Service Los Angeles/Oxnard CA
200pm PDT Monday Oct 18 2021
Expect a cool evening after the cold front moved through the area today. Sunny and warmer conditions are slated for Tuesday through Thursday, with the exception of a slight chance of rain in northwest San Luis Obispo County on Wednesday. A more powerful rain system is expected to arrive over the weekend.
Short Term - Today through Thursday
Synoptically, there is a 548 dam upper low around the CA-NV border that dragged a cold front across our area today. A minor ridge will build in from the south as this system continues its move eastward. A weak trough will just clip the northern part of our area on Wednesday, bringing a slight chance of showers to northwest SLO County. The ridge builds higher on Thursday and should bring the high temperatures of the week, to near normal levels. Ensembles have another trough extending from a closed Gulf of Alaska low impacting the area beginning next Friday or Saturday evening.
Rainfall totals, on today's system were mostly in the hundredths, but as you moved into the foothills or coastal slopes there were several locations with closer to a tenth of an inch. Skies are clear behind the front. Today will be the coldest day of the next 7 with afternoon high temps largely in the mid sixties. Not expecting low clouds and fog tonight because of the recent cold front.
Tuesday morning may have a little frost in interior locations and the Antelope Valley. It will be a sunny day as a weak ridge will move in and heigheights build to 576 dam. Max temps will respond to the higher heigheights and ample sunshine by rising 3 to 6 degrees across the coasts and valleys and 8 to 12 degrees across the mountains and interior. A weak offshore gradient may bump temps even a little higher.
A trough will sweep through the northern half of the state on Tuesday night and into Wednesday, bringing only bring a slight chance of rain to SLO county. The lift ahead of the trough should bring marine layer stratus back to the most of the coastal areas by Wednesday morning. Partly to mostly cloudy skies will follow the morning low clouds as the trough ushers in a slug of mid level moisture. Clouds should counteract and height gain warming and max temps will be similar to Tuesday's readings.
On Thursday the state will still be under the western portion of a growing. Heigheights will be near 585 dam. There will be near neutral flow in the E/W direction and weak offshore flow from the north. It will likely be a mostly cloudy day (perhaps partly cloudy over LA county) as a grip of mid and high level clouds ride up the backside of the ridge. The height rises and lack of onshore flow will more than compensate for the reduced sunshine and max temps will rise 3 to 6 degrees across the area making this the warmest day of the next 7 for most of the forecast area. This warming will bring most max temps to within a degree or two of normal.
Long Term - Friday through Monday
Both the GEFS and EC ensemble show a series of troughs pushing through the state Friday through next Monday possibly bringing a multi day rain event. There is not much consensus on exactly when the axes/fronts move through. Thus the exact timing of rain is still a bit of a question mark. The current model runs keep the bulk of the dynamics and mositure to north of the area on Friday and Saturday. The systems on Sunday and Monday seem a little stronger and further south and right now this seems the best 48 hour window for rain.
GEFS seems a bit faster with the IVT plume forecast from CW3E for around the middle latitude our area being above 250 kg/ms most of the time from the 23rd to the 27th and peaking on Sunday the 24th, while the ECMWF (European Centre for Medium-Range Weather Forecasts) EPS has a higher but more distinct peak on Monday. This is way out in our forecast range, but preliminary analysis shows 1-2" of rain in the Central Coast watershed is a possibility.
Other than the rain chance it looks like it will be a mostly cloudy period with max temps several degrees below normal.
Small Craft Advisory (SCA) level winds continue across the waters from the Central Coast to San Nicolas Island. Moderate to high confidence in SCA (Small Craft Advisory) level winds expanding into the western portion of the Santa Barbara Channel by late this afternoon, and an SCA (Small Craft Advisory) remains in effect for this portion starting at 3pm. SCA (Small Craft Advisory) level winds will likely last through late tonight, then quickly diminish. Winds and seas are then expected to be below SCA (Small Craft Advisory) levels for all coastal waters Tuesday through Thursday. A large NW swell is expected to enter the waters on Friday with moderate confidence in hazardous seas greater than 10 feet across the outer waters through the weekend.
NOAA Los Angeles/Oxnard CA Office: Watches - Warnings - Advisories
CA...NONE. PZ...Small Craft Advisory in effect until 3am PDT Tuesday for zones 645-650-670-673-676.
.HAZARD POTENTIAL OUTLOOK (THU-MON).
A storm system will affect the region this weekend, with over an inch of rain in the forecast for the northern areas.