Point Piedras Blancas to Point Sal from 10 to 60 NM Marine Forecast
|Tonight...Nw Winds 20 To 30 Kt. Combined Seas 7 To 8 Ft Dominant Period 7 Seconds. Patchy Fog After Midnight.|
|Thu...Nw Winds 20 To 25 Kt With Local Gusts To 30 Kt. Strongest Western Portion. Combined Seas 7 To 8 Ft Dominant Period 8 Seconds. Patchy Fog In The Morning.|
|Thu Night...Nw Winds 20 To 30 Kt With Local Gusts To 35 Kt, Becoming 15 To 25 Kt After Midnight. Combined Seas 9 To 10 Ft Dominant Period 8 Seconds. Patchy Fog After Midnight.|
|Fri...Nw Winds 15 To 25 Kt. Combined Seas 8 To 10 Ft Dominant Period 8 Seconds. Patchy Fog.|
|Fri Night...Nw Winds 15 To 20 Kt With Gusts To 25 Kt. Combined Seas 8 To 9 Ft Dominant Period 8 Seconds. Patchy Fog.|
|Sat...Nw Winds 10 To 15 Kt. Wind Waves 2 Ft Or Less. Nw Swell 5 To 7 Ft. Patchy Fog.|
|Sun...Nw Winds 10 To 15 Kt. Wind Waves 2 Ft Or Less. Nw Swell 3 To 4 Ft. Patchy Fog.|
| 216 PM PDT Wed Aug 4 2021 |
Synopsis for the southern California coast and Santa Barbara Channel including the Channel Islands National Marine Sanctuary and National Park - PZZ600
at 20Z, or 1 PM PDT, a 1028 MB surface high was 1000 NM WSW of Eureka CA, while a 1003 MB thermal low was in Arizona. Gusty winds with short period waves will create hazardous conditions for the outer waters today and tomorrow.
| Area Forecast Discussion|
National Weather Service Los Angeles/Oxnard CA
750pm PDT Wednesday August 4 2021
A gradual cooling trend will begin Thursday and continue into the weekend. Night through morning low clouds and patchy dense fog should return to many coastal and valley sections. Gusty afternoon and evening winds and low humidities will elevate the fire risk, mainly across the mountains, Antelope Valley and the Santa Barbara South Coast and adjacent foothills through Thursday.
.SHORT TERM (WED-SAT)...04/748 PM.
Another very warm day in the books, with the far interior areas seeing the highest temperatures of the heatwave. Peak highs in the Antelope Valley ranged from 108 to 111 degrees, with 100 to 103 degrees over interior San Luis County and in the Cuyama Valley. Meanwhile, areas west of the mountains were slightly cooler than yesterday, but with plenty of locations showing triple digit readings. The suite of Excessive Heat Warnings and Heat Advisories for the interior will be allowed to expire at 8 PM this evening. However, overnight lows in the foothills and mountains will remain warm, in the upper 60s to upper 70s. Along the coast, a shallow marine layer has been keeping daytime temperatures in the 70s.
Surface pressure gradients are onshore over Ventura and Los Angeles County, where gusts of 35 to 45 mph are affecting interior passes and canyons into the Antelope Valley. Northerly gradients over Santa Barbara County have so far produced gusts between 45 to 50 mph this evening. With the SBA-SMX gradient increasing to -4.9 mb, expect gusts to increase to between 50-55 mph late this evening, mainly limited to areas west of San Marcos Pass. A Wind Advisory is in effect for this area through 3 AM Thursday, and may need to be extended an additional 2-3 hours.
The marine layer cloud forecast calls for low clouds moving onshore along the Central Coast after midnight into the early morning hours. Further south, the Santa Barbara South Coast is expected to remain clear due to the northerly winds in that area, with possible patchy low cloud coverage on the Oxnard Plain, and coastal L.A. County.
***From Previous Discussion***
Onshore pressure gradients are expected to strengthen in the short term, bringing a stronger sea breeze each day. In regards to fire weather concerns, gusty afternoon winds pushing into interior valleys like the Santa Clarita valley or through Acton and into the high deserts while hot and dry conditions persist will keep an elevated to briefly critical fire risk going into at least Thursday.
For tonight, Gaviota and surrounding environs can expect another round of northwest wind gusts of 50 mph or more. The slightly more widespread and longer duration winds tonight will maintain elevated to brief critical fire weather concerns for the Santa Barbara county mountains and south coast. The south coast of Santa Barbara will see gusty winds Thursday evening as well, but not as strong or widespread as tonight.
Finally, the temperatures will be affected by a combination of lower heigheights and better onshore flow, so Thursday highs will be about 5 to 8 degrees above normal. Further cooling is anticipated for Friday and into the weekend.
Long Term - Sunday through Wednesday
The cooling trend continues into Sunday when temperatures will be near to slightly below normal. It appears there will be little change in temperatures on Monday before the upper level flow turns a bit more southerly and heigheights rise slightly Tuesday into the middle of next week. Tuesday and Wednesday may be a little warmer, especially for the inland sections including the mountains and deserts. The switch in upper level winds to the south may bring the monsoon moisture closer, but not into the district as yet.
High confidence in Small Craft Advisory (SCA) level NW winds continuing through this afternoon from the outer waters along the Central Coast to San Nicolas Island. Good confidence in the current Gale Warning for the outer waters south of Point Sal. It appears that winds will briefly fall below gale force levels Thursday morning, before ramping back up during the afternoon. Guidance still supports gales spreading north of Point Sal on Thursday, therefore a Gale Watch has been issued for the outer waters north of Point Sal for Thursday afternoon/night.
Winds look to quickly diminish on Friday, so moderate confidence in continued SCA (Small Craft Advisory) level winds through Friday night. For the nearshore waters along the Central Coast, high confidence in SCA (Small Craft Advisory) level winds during the afternoon and evening hours through Thursday, with a 30-40% chance of Gales. For the Santa Barbara Channel, moderate to high confidence in SCA (Small Craft Advisory) level winds across the western portion during the afternoon and evening hours through Thursday. There is a 40% chance of SCA (Small Craft Advisory) gusts from Anacapa Island to the Santa Monica Bay as well.
High confidence in very short period and choppy seas continuing over much of the coastal waters through late in the week, with seas building to near 10 ft in portions of the outer waters. A noticeable long period but small (2-3 ft) south swell will continue to build in through Thursday.
NOAA Los Angeles/Oxnard CA Office: Watches - Warnings - Advisories
CA...Heat Advisory in effect until 8pm PDT this evening for zones 38-46-52>54-88-547.
Wind Advisory in effect until 3am PDT Thursday for zones 39-52.
Excessive Heat Warning in effect until 8pm PDT this evening for zone 59.
PZ...Small Craft Advisory in effect until 3am PDT Thursday for zones 645-650. (See LAXMWWLOX). Small Craft Advisory in effect until 2pm PDT Thursday for zone 670. (See LAXMWWLOX). Gale Watch in effect from Thursday afternoon through late Thursday night for zone 670. (See LAXMWWLOX). Gale Warning in effect until 3am PDT Friday for zones 673-676. (See LAXMWWLOX).
.HAZARD POTENTIAL OUTLOOK (SAT-WED).
No significant hazards expected.