| Day | Date | High/Low | Forecast |
| Thu | 5th | 73/55 | Sunny day; Breezy at times, mainly morning. Clear evening and possibly breezy at times. |
| Fri | 6th | 74/58 | Mostly sunny day with some high clouds; Possibly breezy at times early. Mostly clear evening. |
| Sat | 7th | 77/60 | Mostly sunny day with some high clouds; Possibly breezy at times. Some evening high clouds and possibly breezy at times. |
| Sun | 8th | 79/59 | Mostly sunny day with some high clouds; Possibly breezy at times early. Some evening high clouds possible. |
| Mon | 9th | 75/57 | Sunny day. Chance of late evening low clouds. |
Synopsis
Yesterday’s unexpected (by me), persistent marine layer brought slightly cooler than normal weather to areas near the coast (UCLA included). The passage of an “inside slider” type trough this morning, however, has brought back warmer than normal weather (a common theme for a good chunk of winter this season). Since high pressure aloft is forecast to dominate state weather for most of the next two weeks, expect mostly warmer than normal weather for some time (very little chance for widespread, wet weather in California during the period).
Wind speeds in most Santa Ana wind prone areas have lowered this afternoon, Peak wind gusts exceeded 60 mph in some spots (late last night through early this morning). In the Santa Monica mountains above Malibu, a gust to 64 mph was recorded (around 8 AM). A peak wind speed at UCLA was 31 mph (8:50 AM). A relative lull is expected for most of Friday, but again, some brisk wind (particularly higher elevations) should continue. \
By Saturday, another increase in Santa Ana winds are forecast by the numerical models. This happens as a “cut-off”, upper low pressure forms somewhere in Arizona (center circulation winds up over or just west of central Baja California by Sunday). Deep layered wind support will come from the northern half circulation of the low pressure. Since the wind direction aloft should from the northeast to east, wind prone areas around east-west oriented canyons/passes should experience windier weather more than areas around north-south canyons/passes (peak windy areas won’t necessarily repeat over the weekend). UCLA typically doesn’t experience significant winds from the more easterly winds. So, it may not get anywhere as windy over the weekend as it has been today.
One thing that areas west of the mountains should have in common will be the subsidence warming caused by the off-shore flow (reason for today’s noticeable, daytime warming most areas). An influx of polar air into the Mohave desert has limited the warming so far, but the influx should decrease with time. I don’t show it in today’s forecast, but there is a chance for widespread, 80 degree weather in the coastal plain tomorrow/Saturday (shouldn’t get warmer than mid-80s though). If the forecast, “cut-off” low pressure ends up farther south than expected, or it winds up weaker than expected, Sunday could also see widespread 80 degree weather.
The “cut-off” low pressure should start moving east on Monday. At one time, there were some model solutions that favored instability showers over parts of southern California (mainly southern mountains/eastern desert). This scenario now appears very remote (won’t rule out light showers near the eastern state border yet). Weakening off-shore flow, however, should eventually lead to a return of marine layer clouds over the coastal water (as early as Monday evening). A modest cooling trend (west of the mountains) is predicted early next week, but another warming cycle is possible by the middle of next week (high pressure aloft may strengthen back over the Southwest). How warm it gets remains to be seen, but widespread 80 degree weather would be possible (even the chance for isolated 90 degree readings).
There is some uncertainty toward mid-month as some model forecasts show a trough capable of wet weather in California (just a modest sized storm). The usually reliable ECMWF model is currently against this wet scenario.
Next issued forecast/synopsis should be on Monday, 9 March.