08/930 AM.
It will be a little warmer today. Cooler conditions arrive Thursday followed by a chance of rain and thunderstorms Friday and over the weekend.
(tdy-Fri), 08/944 AM.
***UPDATE***
Today will be the warmest day for likely the next several days as onshore flow has weakened and there is high pressure aloft. Highs will be in the 70s and 80s area-wide with coastal valleys being the warmest. Still dealing with some morning stratus in coastal LA County but that will be clearing shortly.
A cooling trend will begin tomorrow and continue through Sunday as two upper lows will move through over the weekend. Rain will be off and on over the weekend with periods of heavy rain and periods of sunny skies. Truly a mixed bag of weather this weekend, even some snow above 5000-6000 feet at times. For most areas rain will be light to moderate with minimal impacts. However, there is the potential for thunderstorms and brief heavy rain, hail, and gusty winds at times that could produce more significant issues, especially if storms are slow moving. Will have a better feel for those possibilities over the next couple days as we move into the range of some of the higher res models.
***From Previous Discussion***
Onshore flow and an eddy will bring low clouds and fog to the csts and many of the vlys including the Paso Robles area Thursday morning. Increasing onshore flow in the afternoon will produce slower than normal clearing. The ridge will push to the east as cool upper low approaches the northern third of the state. The deeper marine layer and stronger onshore flow will cool max temps by 3 to 5 degrees. Despite this cooling most areas will end up 3 to 6 locally 8 degrees warmer than normal.
The 555 dam upper low will not make much progress on Friday and will remain to the west of Humboldt County. Still Srn CA will be under its cool moist cyclonic flow and the clouds and chance of rain will increase through the day from the NW to the SE. The best chc of rain will occur north of Point Conception where rain and a slight chc of TSTMs will occur in the afternoon. LA county may well have to wait until the evening before seeing some rain. Since the storm is so far away the amount of rainfall that will likely fall during the day will only be around a tenth of an inch north of Pt Conception (Higher amounts, as usual, over the far NW tip of SLO county) and a trace to less than a tenth south of Pt Conception. Max temps will plummet 2 to 4 locally 4 to 8 degrees due to the combination of onshore flow, clouds, falling hgts and strong onshore flow. Most max temps will end up 2 to 3 degrees blo normal.
A decent lobe of PVA moves through the area Friday evening and overnight. Rain will be likely across the entire area and there will be a slight chc of TSTMs as well. Most areas will see between a quarter and a third of an inch of rain. But there could be localized areas of higher rainfall amounts in places that experience TSTMs.
(Sat-Tue), 08/227 AM.
The weekend will be cloudy, cool and showery. Friday night's trof will exit the area Saturday morning. Hot on its heels, however, will be an even colder (534 dam) upper low that will sweep into the area and transverse the state by late Sunday. This cold, dynamic and unstable system will bring showers and a chc of TSTMs to the area. On average this system will produce about a half inch of rain over the 2 day period. Rainfall amounts, however, will likely not be too homogeneous due to the convective nature of the system. Some area may only see a quarter inch of rain, while others could see an inch or more. Most rainfall rates will be between 0.25 to 0.75 in/hr but higher rates will be possible under any TSTM that develops. Snow levels will fall to about 6000 ft and several inches of snow is possible above that elevation. Max temps both days will only be in the 60s or 4 to 8 locally 10 degrees blo normal.
There is some chc of lingering showers Sunday night, but by Monday dry NW flow will set up over the area. Both Monday and Tuesday will have mostly clear skies with rebounding temperatures (2 to 4 degrees Mon and 3 to 6 degrees Tuesday).
08/1736z.
At 1655Z at KLAX, the marine layer was 1100 ft deep. The top of the inversion was at 2100 ft with a temperature of 19 C.
Overall, moderate confidence in 18Z TAF Package. Timing of CIG/VSBY restrictions may be off +/- 2 hours and flight minimums by one category.
KLAX, Moderate confidence in TAF. Arrival and clearing times of IFR to low-end MVFR CIGs (007-012) should be accurate within +/- 2 hours from current forecast. There is a 30% chance east wind component reaches 7-8 kts between 09/08Z-16Z.
KBUR, High confidence in VFR TAF.
08/815 AM.
GALE Watch for Santa Barbara Channel (PZZ650) has been cancelled. However, localized GALE force wind gusts are still possible near Santa Cruz Island late this afternoon through this evening.
GALE Watch for the waters between Santa Cruz/Rosa and San Nicolas has been upgraded to a GALE Warning which is in effect this evening through the overnight hours.
All other small craft advisories appear to be on track. Refer to MWWLOX for details.
A storm system with showers and the potential for thunderstorms is expected to move across the coastal waters starting Thursday night lasting through the weekend.
Ca, NONE. PZ, Small Craft Advisory in effect from 2 PM this afternoon to 10 PM PDT this evening for zone 645. (See LAXMWWLOX). Small Craft Advisory in effect from 2 PM this afternoon to 11 PM PDT Thursday for zone 650. (See LAXMWWLOX). Small Craft Advisory in effect from 6 PM this evening to 3 AM PDT Thursday for zone 655. (See LAXMWWLOX). Small Craft Advisory in effect until 11 PM PDT this evening for zone 670. (See LAXMWWLOX). Small Craft Advisory in effect until 11 AM PDT Thursday for zone 673. (See LAXMWWLOX). Small Craft Advisory in effect until 3 PM PDT this afternoon for zone 676. (See LAXMWWLOX). Gale Warning in effect from 3 PM this afternoon to 3 AM PDT Thursday for zone 676. (See LAXMWWLOX).
