10/112 PM.
Light to moderate rain will overspread the area tonight and continue through Wednesday morning. The rain will be accompanied by gusty southerly winds. Rain will taper off Wednesday but lingering showers are possible along the Central Coast through early Thursday. Otherwise, dry weather is expected Thursday through Saturday with warming temperatures. Rain will return Sunday, then off and on through next week.
(tdy-Fri), 10/208 PM.
A classic looking cyclone is approaching the Central Coast this afternoon. There have been a few light showers well ahead of the storm during the day but as of 1pm the primary cold front is just 30-50 miles west of the Central Coast and poised to move onshore this evening. No significant changes have been made to previously discussed rain amounts and hourly rates as the high res models have more or less held steady. This will be a relatively quick moving system, but there will be some pockets of heavy rain at times, especially tonight into early Wednesday. Both the REFS and HREF models still indicate peak rates at around 0.75"/hr, mostly in the mountains, with rates at or below a half inch per hour across coast/valleys. There could be a couple rumbles of thunder tonight as well (better chance north of Pt Conception) but not expecting that to be a widespread feature across the area. Overall rain totals remain very similar to previous estimates, an inch or less across coast/valleys and 1-2" in the foothills and mountains.
The storm is also generating gusty south winds ahead of the cold front to the tune of 30-50 mph, strongest along the Central Coast and in the mountains. Those will start to drop off overnight into Wednesday morning.
Rain will turn to showers by around 4am or earlier and then just scattered showers Wednesday morning until around noon. After that most of the rain will be over. The one exception will be the San Luis Obispo Central Coast where there will be enough lingering moisture and energy to keep light showers going through at late as Thursday morning.
Aside from that, dry and warmer weather is expected through Friday which will be the warmest day for quite some time with highs in the low to mid 70s across the LA/Ventura valleys and 60s to low 70s elsewhere.
(Sat-Tue), 10/206 PM.
Most of the ensemble models are showing dry weather through Saturday before the first of at least three storms arrives on Sunday. There is still uncertainty on timing of the following storms but the ensemble solutions have been quite steady with the rain amounts which looks to be around 2-4" coast/valleys and 3-6" in the foothills and mountains between Sunday and next Wednesday. Snow levels mostly will be around 6000 feet, except they could drop to as low as 4000 or even slightly lower on Wednesday.
That may not be the end of the storm cycle next week as there are some model solutions keeping the door open for additional precip later next week.
10/1916z.
Around 18Z, the marine layer depth was around 3000 feet deep at KLAX. The top of the inversion up to around 3600 feet with a temperature around 11 degrees Celsius.
Moderate confidence through around 00Z, then low confidence due to rain with low ceilings and visibility. Timing could be off by 2 hours. At least brief IFR or lower cigs/vsbys possible in heavier rain focused between 00-06Z KSBA and 06-12Z to the south including KLAX. There is a 5-10 percent chance of a brief thunderstorm, mostly within those same windows. Weak to moderate LLWS is possible especially along and before the period of moderate to heavy rain. Periods of moderate to occasionally strong turbulence and low-level wind shear are possible after 00Z.
KPMD and KWJF: Peak winds may be off by 5-10 kt due to possible mountain wave activity.
KLAX, Moderate confidence in TAF through 00Z followed by low confidence due to timing of flight category changes and wind shifts which could be off by 2-3 hours. 5-10 kt east wind component likely between 00Z-04Z with a south cross wind gusts of likely at times between 03Z-10Z
KBUR, Moderate confidence in TAF through 00Z followed by low confidence due to timing of flight category changes and wind shifts which could be off by 2-3 hours. Periods of moderate to occasionally strong turbulence and low-level wind shear are possible after 00Z.
10/147 PM.
Moderate confidence in the current forecast. Less confidence exists in the swell forecast. Higher confidence exists in the wind forecast.
For the waters southwest through northwest of the Channel Islands and the nearshore waters along the Central Coast, Small Craft Advisory (SCA) conditions will be imminent (80-100 percent chance) by this evening. Likely (50-70 percent) chance of Gale Force southwesterly winds through late tonight, especially for the waters west through north of Point Conception. Chances for SCA conditions for winds will decrease some on Wednesday and Wednesday night SCA conds will likely (50-60 percent) continue due to a mix of wind and seas. A brief lull in the SCA conditions should develop for the daylight hours on Thursday then SCA level winds and higher seas will develop on Thursday evening and likely persist into the weekend.
Inside the southern California bight, SCA level winds are very likely (60-90 percent) by this evening. Winds will likely fall below SCA levels between Wednesday and the end of the week, but there is a moderate to high (30-50 percent) chance of SCA conditions developing each evening across the western portions.
There is a high chance that marine conditions will be poor for the upcoming weekend with rain, large seas, and gusty winds spreading over the area between Friday and Tuesday. There is a moderate to high (30-50 percent) chance of widespread GALES early next week.
10/244 AM.
Lower confidence in the current forecast. A high surf advisory has been expanded across all beaches this due to higher than modeled west to northwest swells moving across the coastal waters this morning, then a southwest swell will develop tonight as gusty southwest winds develop. Southwest and west facing shores will be particularly vulnerable to developing swell and surf tonight and into Wednesday, especially the Santa Barbara South Coast, Ventura County Line, and Leo Carrillo, and Zuma Beach.
Swell and surf will likely drop below high surf advisory criteria for Thursday, but high surf is likely to develop again from Friday. It is likely that the swell and surf will remain at or above high surf criteria through the upcoming weekend.
The latest swell models continue to highlight a period of very large waves developing for early next week. There is a high to likely (50-60 percent) chance of widespread high surf between Monday night and Wednesday. Sets above 10 feet will be possible at west and northwest shores. There is a 20-40 percent chance of damaging sets developing between Tuesday and Wednesday, highest for northwest-facing shores along the Central Coast.
Ca, Wind Advisory remains in effect until 1 PM PST Wednesday for zones 38-344-345-353-376>383. (See LAXNPWLOX). High Surf Advisory in effect until 9 PM PST Wednesday for zones 87-340-346-349-350-354-362-366. (See LAXCFWLOX). Wind Advisory in effect until 4 AM PST Wednesday for zones 340>343-346>349. (See LAXNPWLOX). PZ, Gale Warning in effect until 3 AM PST Wednesday for zones 645-670-673. (See LAXMWWLOX). Small Craft Advisory in effect until 3 AM PST Wednesday for zones 650-655. (See LAXMWWLOX). Small Craft Advisory in effect until 3 PM PST Wednesday for zone 676. (See LAXMWWLOX).
