18/945 AM.
High pressure and offshore flow will bring warm and dry conditions through midweek along with gusty northeast winds at times across Los Angeles and Ventura Counties. A significant cooling trend is expected to begin Wednesday.
(tdy-Tue), 18/952 AM.
***UPDATE***
As expected offshore gradients are slightly weaker today and Santa Ana winds are lighter and more spotty. Still expecting another very warm day with highs in the upper 70s to mid 80s across most coast and valley areas, but areas within a few miles of the beach may be 5-10 degrees cooler than the last few days. Otherwise, more of the same through Tuesday.
***From Previous Discussion***
Warm dry and generally benign weather will continue through Tuesday (and a few days beyond).
Today will feel much like Saturday with an upper over northern Baja and 583 dam hgts over LA county. 3 to 4 mb of offshore flow from both the N and E will keep any low clouds away. Skies, however, will be partly to mostly cloudy as a grip of high clouds drifts overhead. The offshore flow will generate gusty winds in the usual Santa Ana locations, but aside from some isolated advisory level gusts across the ridgetops these gusts will be under advisory levels. Max temps will not change much except along the coasts where there will be 2 to 4 degrees of cooling. Still, most max temps will end up 10 to 12 degrees above normal.
On Monday a weak inside slider will move down the NV/CA state line. Hgts will fall to about 576 dam. Offshore will weak a little bit. Some low clouds are possible across western SBA county and the Long Beach area. Still would not be surprised if these clouds did not develop. The coastal sections will see a few degrees of additional cooling.
The inside slider will usher in a stronger Santa Ana event with 6 to 7 mb of offshore flow from the east along with some cold air advection. This will set up low end advisory level wind event in the morning. The cool air will bring max temps down across the interior and some vlys while the coasts and the rest of the vlys warm a few degrees from the downsloping warming.
(Wed-Sat), 18/1214 AM.
Four days of cooling is on tap for the xtnd period. The ridge that has been parked over the state will shift to put west to the east pac as dry fast moving NW flow moves in from the north. There is some disagreement on Saturday as the EC keeps the NW flow in place while the GFS tries top bring a little ridge back into Srn CA. Hgts should fall from 578 dam Wednesday to to about 570 dam Fri possibly falling to 568 dam Saturday. At the SFC the gradients will weaken considerably and will mostly be within 1.5 mb either side of neutral.
Marine layer stratus will likely redevelop and will affect portions of the coast through the period. Aside from the low clouds, skies will be mostly clear to partly cloudy.
The lowering hgts and lack of significant offshore flow will lead to at least a 3 day cooling trend with cst/vly max temps falling from the lower to mid 70s Wed to the mid to upper 60s on Friday.
The ensembles that were showing a small chc of rain Fri/Sat are now showing only a 10 percent or less chance of rain. Both the AI-GFS and AI-EC keep the area dry through the 27th and then show some chc of rain on the 28th and 29th.
18/1810z.
At 18Z at KLAX, there was no marine layer or inversion.
High confidence in VFR TAFs. There is a 10-20% chance of LIFR/VLIFR conds 06-16Z for coastal sites and KPRB, highest chances for KLGB and KLAX.
KLAX, High confidence in TAF. There is a 20% chance of LIFR/VLIFR 10-16Z. Any east wind component is expected to remain below 8 kt through the period.
KBUR, High confidence in VFR TAF.
18/955 AM.
High confidence in conditions remaining below Small Craft Advisory (SCA) levels through Wednesday, with moderate confidence through Thursday. Peak gusts of 15-20 knots are likely this evening through mid Monday morning for the western Channel Islands to Point Conception with just a 10 percent chance of reach SCA levels.
Localized northeast Santa Ana wind gusts 20-25 knots may occur at times Monday afternoon through Tuesday afternoon between Ventura and Santa Monica (and potentially out to Santa Cruz and Anacapa Islands). Highest chances (50-60% chance) exist Tuesday morning to early afternoon.
Patchy dense fog with low visibilities may continue to impact the coastal waters into next week, with highest confidence across the Outer Waters.
Ca, NONE. PZ, NONE.
