26/223 AM.
A low pressure system will bring cool temperatures, morning drizzle, and gusty winds to the beaches, mountains, and deserts today through Thursday. Winds will be the strongest this afternoon and evening. Friday into early next week a warming trend is likely, with temperatures reaching above normal by Sunday.
(tdy-Thu), 26/223 AM.
An unusual for this time of year upper low will plunge into Nrn CA today and will be centered over Red Bluff later this afternoon. It will spin up a deep marine layer and some local drizzle (esp near foothills). It will keep partly to mostly cloudy skies over most areas through the day. Max temps will cool noticeably (3 to 6 degrees across the csts and 5 to 8 degrees across the vlys). Max temps will only end up in the 60s today across the csts/vlys or 4 to 8 locally 10 degrees blo normal. Winds will be a major issue today as the upper low will bring strong W to NW upper level flow to the area esp the areas north of Pt Conception. Cold air advection with the upper low will help drive these stronger winds down to the sfc. Advisory level gusts will develop across most of SBA and SLO counties as well as the Antelope Vly and the VTA cst.
Wednesday will be similar to today except for the winds. The upper low with a central hgt of 555 dam will be over Bakersfield. This location will shift the strongest upper level winds to the south of LA county and this will reduces the wind speeds over SLO to LA county forecast area. There be another round of morning clouds with partly to mostly cloudy conditions lingering into the afternoon. The upper low is quite dry, but there is enough instability and lift to bring a slight chc of rain to the mtns as well as SLO county and northern SBA county. There is also a slight chc of a TSTM over the mtns if skies stay partly cloudy and allow for some ground heating. Max temps across the csts/vlys will will cool an additional 1 to 2 degrees while the mtns and far interior will see 4 to 8 degrees of cooling. Cst and Vly max temps will only reach the lower to mid 60s. Vly temps will end up 10 to 15 degrees blo normal while the mtns and far interior will be 15 to 20 degrees blo normal.
The low moves northward up to the Sacramento area on Thursday. This will bring better upper level wind support back into the area and the west to northwest winds will pick up again. It is likely that the marine layer will be mixed out at this point so skies will be partly to occasionally mostly cloudy. Still cannot rule out rain across mtns and SLO county. The chc of a TSTM is less than Thursday but still not zero as the area of best instability will be further to the north. Max temps will warm a degree or two as there will be a touch more sunshine but max temps will remain well below normals.
(Fri-Mon), 26/223 AM.
The upper low will pull out of the area Friday and fairly zonal flow will set up over the area. Hgts will rise from 566 dam Friday morning to 575 dam Friday afternoon. Further hgt rises will bring 578 dam hgts Saturday afternoon; up to 582 dam Sunday and then reaching 586 dam on Monday. Pressure gradients will revert back to typical late May with weak onshore flow to the east in the morning turning moderately onshore in the afternoon. In the N/S direction the flow will oscillate between weak offshore in the morning and weak onshore in the afternoon. There will likely be some morning low clouds across the csts and locally into the vlys, but the clouds should be gone by late morning. The sunnier skies and rising hgts will combine to bring a big warm up. Friday should see 3 to 6 degrees of warming across the csts/vlys with 10 to 12 degrees across the far interior. Most areas will warm 4 to 8 degrees on Saturday and 2 to 4 additional degrees on Sunday. This weekend warming should bring near normal temps on Saturday and above normal temps on Sunday. Monday will round out the warm up with 2 to 3 degrees of extra warming. On Monday max temps will be in the mid 70s to lower 80s across the csts and 80s and lower 90s in the vlys.
26/1003z.
At 0832Z at KLAX, the marine layer was 1800 ft deep. The top of the weak inversion was at 5700 ft with a temperature of 15 C.
High confidence in VFR TAFs for desert airfields (KPMD & KWJF).
Low to moderate confidence in remaining sites. Timing of flight cat changes may be off +/- 2 hours. There is a 30 percent chc of SCT conds in the afternoon.
KLAX, Moderate confidence in TAF. Cigs could arrive as late as 14Z. VFR conds could arrive as early as 18Z. There is a 30 percent chc of SCT conds in the afternoon. No significant easterly wind component is expected.
KBUR, Moderate confidence in TAF. Cigs could arrive as early 09Z. Cigs could range from 015 to 025. There is a 30 percent chc of SCT conds in the afternoon.
26/228 AM.
For the Outer Waters, moderate to high confidence in current forecast. Small Craft Advisory (SCA) levels are expected through most of this afternoon. Then, a GALE WARNING goes in effect from mid to late afternoon through late tonight. SCA conditions will then follow through Wednesday night, or Wednesday afternoon for PZZ676. Thereafter, conditions are likely to fall below SCA levels for a short-time, before returning Friday night into the weekend. For the Inner Waters north of Point Sal, moderate confidence in current forecast. Today through early Wednesday, high confidence in a combination of at least SCA level winds (strongest in the afternoon and evening hours) along with SCA seas. A GALE WARNING goes into effect this afternoon through late tonight. Conds should drop below SCA levels by Wednesday afternoon.
For the Inner Waters south of Point Conception, moderate confidence in current forecast. SCA level W to NW winds are expected across the Santa Barbara Channel today, around the Channel Islands, and into Santa Monica Bay during the evening hours. A GALE WARNING goes in effect for the Santa Barbara Channel this afternoon through late tonight, and local Gale Force winds could occur nearshore Anacapa island during this timeframe. SCA level winds could linger into Wednesday especially across the channel. Otherwise, expecting conditions to fall below SCA levels thereafter.
Ca, Wind Advisory remains in effect from 2 PM this afternoon to 10 PM PDT this evening for zones 340-341-346>348-354. (See LAXNPWLOX). High Surf Advisory in effect from 5 PM this afternoon to 11 PM PDT Wednesday for zones 340-346. (See LAXCFWLOX). Wind Advisory remains in effect from 6 PM this evening to 6 AM PDT Wednesday for zones 349-351. (See LAXNPWLOX). Wind Advisory remains in effect from 11 AM this morning to midnight PDT tonight for zones 381>383. (See LAXNPWLOX). PZ, Small Craft Advisory in effect from 8 AM this morning to 3 PM PDT this afternoon for zone 645. (See LAXMWWLOX). Gale Warning in effect from 3 PM this afternoon to 3 AM PDT Wednesday for zones 645-650-670-673-676. (See LAXMWWLOX). Small Craft Advisory in effect until 3 PM PDT this afternoon for zones 650-670-673-676. (See LAXMWWLOX). Small Craft Advisory in effect from 3 PM this afternoon to 3 AM PDT Wednesday for zone 655. (See LAXMWWLOX).
