17/821 PM.
Dry and warmer weather is expected into the weekend, though a cooling trend will begin Sunday as a low pressure system approaches. Rain chances will begin as early as Monday night along the Central Coast and Tuesday in Los Angeles.
(tdy-Mon), 18/355 AM.
Another warm day is expected today, with temperatures increasing by a few degrees compared to yesterday, though high clouds in the area may somewhat moderate daytime heating. Highs will be about 6 to 12 degrees above normal, with widespread highs in the upper 70s to mid 80s. Below advisory level east winds (25 to 35 mph gusts) are expected to redevelop across the typical Santa Ana Wind Prone areas of LA and Ventura Counties through this morning. These winds and a generally warmer airmass aloft will yield the modest warming trend for today.
Sunday and Monday, temperatures will cool a couple degrees each day, as a cutoff low approaches the region. 500 mb heights are expected to fall and onshore flow will increase to moderate strength during the afternoon. Marine layer stratus is likely to increase at this time as well. As the center of the low travels farther south along the California Coast, light rain will become possible for northwestern San Luis Obispo County Monday evening, with chances spreading south to Santa Barbara County Monday night.
(Tue-Fri), 18/418 AM.
Monday night through Wednesday, a cutoff low is expected to scoop across the state, with the center of the low remaining north of the Bay Area. Rain is near certain for San Luis Obispo and Santa Barbara Counties between Monday night and Wednesay. Timing continues to be uncertain, but Tuesday is the most likely day for rain overall. For Ventura and Los Angeles Counties, there is around a 50-70% chance of some rain, though totals are likely to be much lighter compared to up north. Exact rain amounts are difficult to narrow down at this point especially for the northern counties. Across San Luis Obispo and Santa Barbara Counties, between 0.25 to 1.0 inches are likely, and for Ventura and Los Angeles Counties between 0.1 to 0.5 inches are likely. There are some ensemble members that show 2+ inches for the Central Coast, which may occur if the trajectory of the center of the low drops farther to the south. There is also a small chance for thunderstorms and heavier rain showers/rates for San Luis Obispo County and northern Santa Barbara County on Tuesday.
Gusty winds are expected with the storm, especially across the coasts, mountains, and deserts. Winds will be greatest on Tuesday evening along the Central Coast (southerly), and Wednesday evening for Ventura and Los Angeles Counties (westerly).
18/1207z.
At 07Z at KLAX, the marine layer was 500 ft deep, with an inversion up to 1100 feet with a maximum temperature of 19 C.
High confidence for TAFs, except moderate confidence for KLAX and KLGB that may (10-20% chance) see brief MVFR conditions from 14-17Z.
KLAX, Moderate to high confidence in TAF. There is a slight (10%) chance of MVFR conditions from 15Z-17Z. The east wind component is not expected to exceed 6 kt.
KBUR, High confidence in TAF.
18/356 AM.
For the Outer Waters, moderate to high confidence in current forecast. There is a 30-40% chance of SCA level winds today, followed by lighter winds through Sunday. An approaching cold front has a small chance of producing SCA-level southerly winds, along with a chance of showers between Monday evening and Tuesday morning. Wednesday into Wednesday night, increasing NW flow is forecast, with a good chance of SCA level winds.
For the Inner Waters north of Point Sal, moderate to high confidence in current forecast. Today through Tuesday, fairly high confidence in winds and seas remaining below SCA levels, however an approaching cold front will bring increasing southerly winds, along with a chance for showers between Monday evening and Tuesday morning. Increasing NW winds expected Wednesday and Wednesday night, with SCA winds possible by the evening.
For the Inner Waters south of Point Conception, moderate to high confidence in current forecast. From Point Mugu to Malibu there is a a low chance (10%) of SCA gusts nearshore below any canyons/passes this morning. This afternoon through Tuesday, moderate to high confidence in winds and seas remaining below SCA criteria for all southern Inner Waters. Winds will begin to increase of Tuesday from the NW, with SCA speeds possible by Wednesday afternoon or evening
Ca, NONE. PZ, NONE.
