17/800 PM.
High pressure and offshore flow will bring very warm and dry conditions to the region through the weekend along with gusty northeast winds at times across Los Angeles and Ventura Counties. Well above normal temperatures are expected at least into early next week. A significant cooling trend is expected to begin the middle of next week.
(Sat-Tue), 17/800 PM.
***UPDATE***
The offshore winds will continue to prevail, but also continue to weaken through at least Monday (much to the annoyance of everyone will allergies). Isolated advisory level gusts (up to 45 mph) will continue to be possible across the typical Santa Ana wind- favored mountains in Los Angeles and Ventura counties through Sunday morning. High temperatures will lower a few degrees on Sunday compared to the readings today, thanks to the weakening offshore flow. While there is a slight chance of low clouds and fog sneaking into coastal areas, higher clouds will continue to stream through the skies through tomorrow morning. All in all, pretty benign weather will continue, with the main story of temperatures continuing above normal for this time of year.
The forecast looks in shape, and no updates were needed.
***From Previous Discussion***
Santa Ana conditions continue, now going into its tenth day. Offshore gradients pulsed up slightly today but upper level wind support has been lacking and advisory level winds have been very isolated. Models continue to indicate offshore flow in place through next Wednesday, weakening Sunday and Monday, but then pulsing up again Tuesday. Areas near the beaches will be the most susceptible to bigger day to day temperature changes and possible stratus/fog development based on the strength of the offshore flow that day. Elsewhere, very little change is expected with sunny skies, highs in the upper 70s to mid 80s (10-15 degrees above normal), and some local northeast winds in the usual favored areas of LA/Ventura Counties.
(Wed-Sat), 17/117 PM.
A significant cooling trend across coast and valleys will begin in earnest next Wednesday as this persistent offshore flow finally turns onshore and cool maritime air can move inland. High pressure aloft will still be in place and longer term the upper level pattern still favors a ridge over the eastern Pacific Ocean, but a return to normal temperatures is expected the remainder of next week with more typical light to moderate onshore flow.
As far as rain chances go, they are still very low through next week as the West coast ridge remains dominant at least through early the following week (Jan 26). There have been a handful of ensemble solutions, roughly 5-10 percent, showing some energy undercutting the ridge and possibly bringing some very light rain later next week (Fri/Sat ish), but most of the models are holding off until even later in the month, around the 29th, before there are any appreciable chances for rain locally.
18/0527z.
At 0415Z at KLAX, there was no marine layer. There was a surface inversion to 1300 feet with a temperature of 23 degrees C.
High confidence in VFR valley and desert TAFs. Moderate to high confidence in coastal site TAFs, where there is a 10% chance of LIFR/VLIFR conditions 08Z-17Z. Timing of transition to onshore flow at KOXR and KCMA may be off +/- 3 hours, and there is a 30% chance for no W winds at KCMA.
Gusty northeast winds into the evening will generate light to locally moderate LLWS and turbulence across the foothills and mountains.
KLAX, High confidence in TAF. There is a less than 10% chance of BKN002-004 1/4-1/2SM FG conditions 10Z-17Z. No significant east wind component is expected.
KBUR, High confidence in TAF.
17/802 PM.
For the Outer Waters, and Inner Waters north of Point Sal, high confidence in current forecast. Winds and seas will remain below Small Craft Advisory (SCA) levels through Thursday.
For the Inner Waters south of Point Conception, moderate to high confidence in current forecast. For most of the waters, high confidence in winds and seas remaining below SCA levels through Thursday. The only exception will be a 40-50% chance of SCA level northeast winds from Ventura south to Santa Monica on Tuesday.
Patchy dense fog with low visibilities will continue to impact the coastal waters through the weekend, most significantly along the Outer Waters.
Ca, NONE. PZ, NONE.
