25/118 PM.
Hotter than normal conditions will continue for the foreseeable future, generally hottest through Sunday. Slight cooling is expected Monday through Wednesday, with heat increasing again Thursday into the weekend. The hot daytime and warm night conditions will bring elevated risks of heat-related illness. Gusty NW winds will affect SW Santa Barbara County at times, with gusty onshore winds over the interior.
(tdy-Tue), 25/118 PM.
The heat continues to be the main story weather-wise for the next week. The upper level high pressure that has been sitting over the four corners region of the states will change very little in the short term. 500 mb heights will stay around the same over Southwest California, ranging between 592-594 dam.
Temperatures will be similar each day in the short term with highs in the 80s to 90s away from the coast, high 90s to 105 across the coastal/interior valleys, and 100 to 108 degrees across the Antelope Valley. Additionally, warm overnight lows are expected to continue with lows in the 60s and 70s. Widespread Heat Advisories and the Extreme Heat Warning are still in effect through Monday, though advisories may need to be extended into at least Tuesday. Additionally, Precipitable Water (PWATs) are still ranging from 1.0 to 1.5 inches across the region, causing the muggy/humid feeling and adding to the discomfort from the heat.
Clouds will be fairly similar each night through morning. One exception is low clouds may be a little bit less expansive Sunday night due to onshore flow weakening between 3 to 4 mb from both the north and south. However on Monday and Tuesday, onshore flow will once again restrengthen.
As for winds, Southwest Santa Barbara will see gusty sundowners each evening along with NW winds strengthening through the I-5 corridor around the same time period. The Antelope Valley foothills will also see some gusty SW winds each afternoon. However, winds will likely remain below advisory levels each day, and there is a 30 percent chance that an advisory will be needed for the Sundowners.
Lastly, several of the models show ample moisture at 700 mb rotation around the upper level ridge and into Southern California on Sunday. This moisture is from afternoon convection over Mexico, which includes a couple of weak disturbances. Fat drop light showers are possible anywhere in Los Angeles and maybe Ventura Counties during this period. The mountains and deserts have the highest chances and decided to add some slight chances for Sunday afternoon and evening. This impulse also carries a 5 to 10% chance for thunderstorms, which could be a fire ignition source.
(Wed-Sat), 25/117 PM.
The large area of high pressure will continue to impact the region through the long term. The center of the high pressure will move slightly east Tuesday through Wednesday, bringing some relief from the heat, but only by a few degrees. Coastal areas will see the most noticeable drop in temperatures as onshore gradients strengthen, allowing low clouds and fog to expand some. Additionally, PWATs will finally drop below 1 inch by Tuesday afternoon, meaning it will be/feel less humid than it has been these past few weeks.
The majority of the ensemble solutions show the ridge of high pressure pushing back to the west around Friday or Saturday of next week. This will likely push temperatures back up a few degrees, but the warming may be mainly focused over the mountains and interior valleys as the onshore flow changes little. Thankfully, PWATs are not forecast to increase drastically like they have over the last week or two of warm ups the region has had, which means the air will feel drier than it has.
25/1800z.
At 1654Z over KLAX, the marine layer was 1400 ft deep. The top of the inversion was 3500 ft with a max temperature of 28 Celsius.
High confidence in VFR conditions through Sunday at KPRB, KSBP, KSBA, KBUR, KVNY, KPMD AND KWJF. Chances for MVFR cigs at KOXR until early this afternoon is high. Chances for cigs tonight into Sunday morning, LIFR/IFR conds at KSMX (70%), IFR/MVFR conds at KOXR (60%) KCMA (60%) KSMO (60%) KLAX (70%) KLGB (80%). Timing of onset of low clouds tonight may be off +/- an hour or two. Winds will be similar to last 24 hours.
KLAX, 60% chance of BKN010-012 11-17Z Sunday. High confidence in any east winds staying under 6 knots.
KBUR, High confidence in VFR through Sunday with typical winds.
25/118 PM.
For the outer waters, generally high confidence in the current forecast. Gale force winds will affect the waters north and west of the Channel Islands tonight, otherwise Small Craft Advisory (SCA) level winds can be expected most of the time through Thursday night. SCA level seas will be prevalent much of the time thru the period. Steep choppy seas can be expected much of the time as well.
For the inner waters north of Point Sal, generally high confidence in the current forecast. SCA level wind gusts should be prevalent much of the time through Wednesday evening followed by conds dropping below SCA levels for Thursday and Thursday night. Steep choppy seas can be expected much of the time as well.
For the southern inner waters, generally high confidence in the current forecast. The western Santa Barbara Channel will likely see SCA level wind gusts at times mainly afternoon and evening hours through Tuesday. Otherwise, conds will remain below SCA levels through Thursday night.
25/126 PM.
A long period, southern hemisphere swell will add to the continuing swell from Hurricane Fausto. This swell will result in an increased risk of dangerous rip currents across the coastal beaches, as well as elevated surf of 3-6 ft across the Los Angeles and Ventura County Beaches.
Therefore, a Beach Hazard Statement is in effect at least through the weekend for Los Angeles and Ventura County beaches and the Central Coast beaches. Rip currents and elevated surf will be strongest across south to southwest facing beaches and harbors such as Avila Beach.
The Eastern Pacific looks to remain active with Hurricane Genevieve forecast to track well south and southwest of the southern tip of Baja California over the next 5 days. This will result result in additional southerly swells to impact the coastline through the middle of next week. As a result, the Beach Hazards Statement has been extended through Wednesday for south and southwest facing beaches.
Ca, Heat Advisory remains in effect until 8 PM PDT Monday for zones 38-88-342>345-348>358-362-366>382-548. (See LAXNPWLOX). Beach Hazards Statement in effect through Wednesday afternoon for zones 340-346. (See LAXCFWLOX). Beach Hazards Statement in effect through Sunday evening for zones 354-362-366. (See LAXCFWLOX). Extreme Heat Warning in effect until 8 PM PDT Monday for zone 383. (See LAXNPWLOX). PZ, Small Craft Advisory in effect until 6 PM PDT Monday for zones 645-676. (See LAXMWWLOX). Small Craft Advisory in effect from 6 PM this evening to 6 PM PDT Sunday for zone 650. (See LAXMWWLOX). Gale Warning in effect until 3 AM PDT Sunday for zones 670-673. (See LAXMWWLOX).
