17/456 PM.
A stormy pattern will continue for most of the week, with periods of heavy rain moving north to south across the area tonight. There will be lulls in the shower activity much of the day Wednesday, followed by additional rain Thursday. Afternoon high temperatures will mostly be in the 50s through Thursday. Friday and Saturday are expected to be dry but another storm is possible for Sunday and the middle of next week.
(Tue-Fri), 17/822 PM.
***UPDATE***
***RESIDENTS ARE URGED TO TAKE DOWN ANY AWNINGS OR UMBRELLAS AND AVOID PARKING CARS NEAR TREES.***
Rain, thunderstorms and strong winds will affect Southwest California tonight as a line of convection moves south over the area. Currently the line is oriented from southwest to northeast across San Luis Obispo County and pushing into the northwest portion of Santa Barbara County. Frequent lightning is occurring with rain up to 0.5 inch per hour and wind gusts up to 60 mph. Brief, weak tornadoes may develop within the stronger storms in this band. The damaging wind gusts have a high likelihood of blowing down trees, tree limbs and powerlines, with potential for destruction of other objects.
While the overall rainfall totals won't be as high as the previous storm, there is a possibility of very heavy bursts of rain along with the strong wind gusts. The models indicate a chance of gusts over 70 mph in the mountains and Antelope Valley overnight. Additional rainfall totals will be up to 1.50 inches for most areas, except for 2-4 inches in the mountains and foothills.
Finally, with much colder air moving into the area, snow levels will drop rapidly tonight. Recent reports indicate snowfall at around 5100 feet, but the snow levels will lower further to near 3000 feet or lower overnight. Mountain passes in the area are likely to see accumulating snow, with 1 to 3 inches of snow tonight into early Wednesday on the Grapevine. Local snowfall up to 4 inches will be possible there, potentially causing delays or closures.
Storm activity should wind down fairly quickly Wednesday morning, with lingering isolated showers across the area, most numerous along the Central Coast. Otherwise, it will a cool day and evening with breezy west to northwest winds.
***From Previous Discussion***
The next system is still on track for Thursday and exiting late in the afternoon and evening with again some cool and breezy west to northwest winds to follow. Several inches of additional snow are expected in the mountains, especially above 5000 feet. Snow levels are likely to reach 4000 feet Thursday morning and again Thursday night into Friday morning when snow could accumulate over Interstate 5. Rain amounts expected to be around a quarter to half inch for coast/valleys and up to an inch in the mountains. Slightly higher amounts possible north of Pt Conception due to the favorable northwest wind maintaining showers there longer. Lingering north slope snow showers near the Grapevine are possible into Friday morning potentially impacting the road there.
Dry but very cool Friday. Possibly some morning frost or freeze conditions in the valleys depending on how quickly the storm clears out and how much wind lingers overnight.
(Sat-Tue), 17/108 PM.
Saturday will be the nicest day of the next 7 as a weak ridge passes overhead. It will be a mostly sunny and dry day. 3 to 6 degrees of warming will bring max temps up into the 60s.
Another large Gulf of Alaska system moves down and into the PACNW Sunday and bring moist cyclonic flow to Srn CA once again. The ensembles are all over the place and the forecast broad brushes 30-40 percent chances of rain across the entire area Sunday through Tuesday. This reflects mdl confusion and not a three day rain event. This system does not look like it has that much moisture to work with and rainfall amounts at this time do not look that impactful.
There is another storm that models are targeting for later next Tuesday into Wednesday but this one appears to be a weaker system with snow levels at or above 10,000 feet.
18/0050z.
At 2348Z at KLAX, there was no marine layer or marine inversion.
Overall, low confidence in the 00Z TAF package. Shower activity through the period will result in conditions bouncing between VFR and MVFR CIGs with IFR VSBY at times. Low confidence in timing of these flight category changes. There will also be a 15-30% chance of TSTMs in the 00Z-15Z time frame with the highest chances north of Point Conception.
Strong and gusty southwesterly winds will develop later this afternoon and evening, before shifting to the northwest by Wednesday morning. Confidence in wind speeds is low as values could be up to 10 knots lower than forecast.
KLAX, Low confidence in the 00Z TAF. Increasing shower threat through the period will result in conditions bouncing between VFR and MVFR levels, but confidence in timing remains low. There is a 15% chance of TSTMs in the 02Z-15Z time frame. Lower confidence in the magnitude of gusty SW winds this evening and tonight, with a shift to W winds expected by around 11Z.
KBUR, Low confidence in the 00Z TAF. Increasing shower threat through the period will result in conditions bouncing between VFR and MVFR levels, but confidence in timing remains low. There is a 15% chance of TSTMs in the 02Z-15Z time frame. Gusty winds forecast tonight could be up to 10 knots weaker than currently forecast.
17/823 PM.
A line of strong thunderstorms is moving over the waters from north to south tonight with frequent lightning and wind gusts at strong Gale Force (40 to 45 knots). The line is south of PZZ670 and PZZ645 and approaching Point Conception as of 0800 PM PST. Wind gusts of 40 to 45 knots with possible isolated Storm Force gusts will be possible ahead of and along with this line of storms. In addition, seas are building rapidly as a large westerly swell combines with large southerly wind-driven seas.
For the Outer Waters, moderate to high confidence in current forecast. Through Wednesday morning, high confidence in GALE FORCE winds and Small Craft Advisory (SCA) level seas. From Wednesday afternoon through Friday, high confidence in a combination of SCA level winds and seas. For Saturday, high confidence in winds and seas remaining below SCA levels. On Sunday, there is a 40-50% chance of a combination of SCA level winds and seas.
For the Inner Waters north of Point Sal, moderate to high confidence in current forecast. Through Wednesday morning, high confidence in GALE FORCE winds and SCA level seas. From Wednesday afternoon through Friday, high confidence in a combination of SCA level winds and seas. For Saturday, high confidence in winds and seas remaining below SCA levels. On Sunday, there is a 40-50% chance of a combination of SCA level winds and seas.
For the Inner Waters south of Point Conception, high confidence in current forecast. GALE FORCE winds will develop late this afternoon and evening, and continue through Wednesday morning. From Wednesday afternoon through Friday, SCA level winds are expected while seas remain below SCA levels. For Saturday and Sunday, winds and seas will remain below SCA levels.
17/803 PM.
A period of very large waves will move across the coastal waters through Friday, with surf generally peaking tonight and Wednesday across west facing beaches. High Surf Advisories and Beach Hazard Statements are in effect for all coasts, please see the CFWLOX and SRFLOX products for more details.
Elevated high tides as the new moon cycle approaches will coincide with the arrival of the higher surf and swell. This will bring an elevated chance of coastal flooding or minor tidal overflows during the time of the high tides this evening and especially Wednesday morning.
Ca, Flood Watch in effect until 3 AM PST Wednesday for zones 38-340>353. (See LAXFFALOX). Wind Advisory in effect until 3 AM PST Wednesday for zones 38-340>349-351. (See LAXNPWLOX). Wind Advisory remains in effect until 6 AM PST Wednesday for zones 88-350-352-354>358-362-366>375-548. (See LAXNPWLOX). Flood Watch in effect until 6 AM PST Wednesday for zones 88-354>358-362-366>383-548. (See LAXFFALOX). High Surf Advisory in effect until 10 PM PST Friday for zones 340-346-354-362-366. (See LAXCFWLOX). Beach Hazards Statement in effect through Wednesday morning for zones 349-350. (See LAXCFWLOX). Winter Storm Warning now in effect until 7 AM PST Friday for zones 353-376>382. (See LAXWSWLOX). Wind Advisory remains in effect until 10 PM PST this evening for zone 383. (See LAXNPWLOX). High Wind Warning remains in effect until 6 AM PST Wednesday for zone 383. (See LAXNPWLOX). PZ, Gale Warning in effect until 9 AM PST Wednesday for zones 645-650-655-670-673-676. (See LAXMWWLOX).
