Point Piedras Blancas to Point Sal from 10 to 60 NM Marine Forecast
|Tonight...Nw Winds 10 To 15 Kt, Becoming 5 To 10 Kt After Midnight. Wind Waves 2 Ft Or Less. Nw Swell 5 To 6 Ft At 10 Seconds.|
|Thu...Nw Winds 5 To 10 Kt, Becoming 10 To 15 Kt In The Afternoon. Wind Waves 2 Ft Or Less. Nw Swell 4 To 5 Ft At 10 Seconds.|
|Thu Night...Nw Winds 10 To 20 Kt. Wind Waves 2 To 3 Ft. Nw Swell 3 To 4 Ft At 9 Seconds. Patchy Fog After Midnight.|
|Fri...Nw Winds 10 To 15 Kt With Gusts To 20 Kt, Becoming 15 To 20 Kt With Gusts To 25 Kt In The Afternoon. Wind Waves 2 To 4 Ft. Nw Swell 3 To 4 Ft At 7 Seconds. Patchy Fog In The Morning.|
|Fri Night...Nw Winds 15 To 25 Kt. Combined Seas 5 To 6 Ft Dominant Period 7 Seconds. Patchy Fog After Midnight.|
|Sat...Nw Winds 15 To 20 Kt With Gusts To 25 Kt. Combined Seas 4 To 5 Ft Dominant Period 7 Seconds. Patchy Fog In The Morning.|
|Sat Night...Nw Winds 15 To 25 Kt With Gusts To 30 Kt. Combined Seas 5 To 6 Ft Dominant Period 7 Seconds.|
|Sun...Nw Winds 10 To 20 Kt With Gusts To 25 Kt. Wind Waves 2 To 4 Ft. Nw Swell 3 To 4 Ft.|
|Mon...Nw Winds 15 To 25 Kt With Gusts To 35 Kt. Combined Seas 6 To 8 Ft. Patchy Fog.|
| Area Forecast Discussion|
National Weather Service Los Angeles/Oxnard CA
201pm PDT Wednesday April 14 2021
A deep marine layer will keep cloudy skies over most areas except the interior today with partial afternoon clearing. Temperatures will be cool today with a warming trend Thursday through the weekend with reduced marine layer cloud coverage.
.SHORT TERM (TDY-SAT)...14/159 PM.
Overall, 12Z models in good synoptic agreement through the short term period. At upper levels, low drops across the Great Basin tonight then moves eastward with cyclonic flow remaining over our area through Saturday. Near the surface, onshore flow will decrease through the period with some weak northerly offshore gradients in the evening/overnight hours.
Based on 12Z model guidance, the overall forecast thinking has not changed. Currently, sounding data indicates a deep moist layer near 5000 feet with some stratocu observed on satellite across the Central Coast as well as Ventura/LA counties. For tonight and Thursday, expect inversion to settle in at a lower elevation and stratus should be more organized tonight/Thursday morning with a good dissipation Thursday afternoon. For Thursday night through Saturday, the weakening onshore gradients will result in less extensive stratus coverage each night with continued good dissipation each afternoon. Other than any potential stratus, skies should remain mostly clear through Saturday.
As for winds, moderate onshore gradients are generating gusty winds across the Antelope Valley and LA mountains. Other than the wind tunnel known as Lake Palmdale, gusts are expected to remain below advisory levels through this evening. With the onshore gradients diminishing through Saturday, onshore winds will continue be weaker day-to-day. Other wind concern is the northerly offshore gradients forecast the next few evenings. High resolution models indicate slightly stronger northerly gradients each evening. So, will expect some locally gusty north wind across the Santa Ynez Range and I-5 Corridor through Friday night, but any advisory-level winds are expected to be localized.
As for temperatures, will expect a gradual warming trend each day with most coastal/valley areas a few degrees above seasonal normals by Saturday.
.LONG TERM (SUN-WED)...14/159 PM.
For the extended period, main concern continues to be the warm and dry conditions anticipated on Sunday and Monday. At upper levels, both the GFS and ECMWF (European Centre for Medium-Range Weather Forecasts) pinch off a low over Arizona on Sunday and move the feature eastward on Monday, generating some northeasterly flow over the area. Near the surface, weak offshore gradients will develop on Sunday with some weak onshore gradients developing on Monday. Based on surface gradients and upper level winds, do not anticipate any widespread advisory-level Santa Ana winds on Sunday. However, the offshore flow and a warmer boundary layer will bring well above normal temperatures to the area Sunday and Monday. Looking at local TEMP STUDY database with various combinations of surface gradients and low-level temperatures, widespread 80s are expected across most areas on Sunday and Monday. Based on gradient trends, coastal areas will have warmest temperatures on Sunday with interior sections the warmest on Monday. As the temperatures increase Sunday and Monday, conditions will be very dry. So, elevated fire weather conditions can be expected for the area.
For Tuesday and Wednesday, forecast confidence drops dramatically as ECMWF swings a couple of upper level lows over the area while the GFS has an upper level ridge along the West Coast. Either solution would bring cooler conditions to the area although the ECWMF solutions would be noticeably cooler than the GFS. So, will continue with previous forecast thinking of cooler temperatures Tuesday/Wednesday with some return of coastal stratus to hedge our bets between the two solutions. Hopefully, the models will come into better consensus in the coming days.
Overall, moderate to high confidence in forecast. Other than some lingering Small Craft Advisory (SCA) level gusts around the Channel Islands and southward through the early morning, winds and seas will remain below SCA (Small Craft Advisory) level through tonight. There is a 30% chance of some local and brief SCA (Small Craft Advisory) level gusts this afternoon and early evening from the Channel Islands to San Nicolas Island. By Thursday afternoon, the same area will see about a 50% chance of SCA (Small Craft Advisory) level gusts. Much better confidence in widespread SCA (Small Craft Advisory) level winds extending from the Central Coast to San Nicolas Island (and potentially the western portion of the Santa Barbara Channel) by late Friday afternoon or early evening. Very good confidence that these gusty winds will last through the weekend and into early next week.
.LOX WATCHES/WARNINGS/ADVISORIES... CA...NONE. PZ...NONE.
.HAZARD POTENTIAL OUTLOOK (SAT-WED).
No significant hazards expected.