textproduct: Los Angeles

SYNOPSIS

09/1138 PM.

Today will be mostly cloudy and cooler. Light to moderate rain will overspread the area tonight and continue through Wednesday morning. The rain will be accompanied by gusty southerly winds. The rest of Wednesday and Thursday will be partly cloudy with max temps a few degrees under normal. Look for clearing skies on Friday with warmer temperatures on Friday. Most of Saturday will be dry but a series of cold storms is likely starting Saturday night and lasting deep into next week.

LONG TERM (FRI-MON)

10/255 AM.

A fast moving ridge will move into and over the area on Friday. Offshore flow will develop as well and there will be some sub advisory morning NW winds across the coasts and vlys of VTA/LA counties and portions of the Central Coast. Take advantage of the day if you can as the sunny skies will not last for long. Max temps will rise 4 to 6 degrees and max temps will end up in the upper 60s and lower 70s across the csts and vlys.

On Saturday the ridge will move to the east and will be replaced by SW flow ahead of an upper low. There will be enough mid level clouds in the upper flow to make it a partly cloudy day. The lack of offshore flow will result in several degrees of cooling across the csts/vlys.

There are enough ensemble members showing some rain Saturday night but the overall mdl trend has been slower and feel that the chc of rain here is overdone. This trend continues into Sunday where the latest ensemble based solutions show rain overspreading the entire area during the day. Almost all current mdls (esp the AI mdls) show a much later arrival time and would not be surprised if this wet Sunday fcst is dialed back over the next few days.

AI and Ensembles both agree that three storms will affect the area during the week of the 16th to the 21st. Timing and intensity are still somewhat uncertain although early indications say that the biggest system will affect the area mid week. It looks fairly certain that these will be the coldest systems of the year with plenty of snow at lower than normal levels. Stay tuned to this product for daily updates on the evolutions of these systems.

AVIATION

10/1119Z.

Around 0730Z, the marine layer depth was around 700 feet deep at KLAX. The top of the inversion up to around 1500 feet with a temperature around 16 degrees Celsius.

For coastal and valley terminals, moderate confidence in the current forecast through 03Z Wednesday, then low to moderate confidence thereafter due to rain with low ceilings and visibility. Timing could be off by as much as 2 hours. IFR to MVFR conditions will be prevalent this morning, then MVFR to VFR conditions with ceilings at or below 6000 feet will be prevalent through 03Z Wednesday. MVFR conditions with local IFR conditions will likely develop in rain after 03Z.

KLAX...IFR to MVFR conditions will be prevalent through 18Z at the latest, then MVFR to VFR conditions with ceilings at or below 6000 feet will be prevalent through 23Z. MVFR conditions could develop in rain as early as 04Z Wednesday but more likely after 07Z Wednesday. Easterly winds between 6 and 10 knots will occur through 17Z, then shift to south this afternoon. Easterly winds greater than 10 knots are likely to develop between 23Z and 02Z Wednesday, then there is a high chance of southerly cross winds with gusts between 15 and 25 knots after 05Z Wednesday. Periods of moderate to occasionally strong turbulence and low-level wind shear are possible after 04Z.

KBUR...IFR to MVFR conditions could spread into KBUR as soon as 13Z, or as late as 16Z. There is a 30 percent chance of no IFR conditions developing. MVFR to VFR conditions with ceilings at or below 6000 feet will be prevalent after 18Z, then MVFR conditions in rain could develop as early as 04Z Wednesday but more likely after 07Z Wednesday. There is a 30 percent chance of IFR conditions in heavy rain after 07Z. Southeasterly winds between 15 and 25 knots could develop as soon as 23Z but are more likely after 05Z Wednesday. Periods of moderate to occasionally strong turbulence and low-level wind shear are possible after 02Z.

MARINE

10/320 AM.

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. SCA conditions due to marginally high seas will linger through midday, then there is a high to likely (50-70 percent) chance of Gale Force southwesterly winds between from this afternoon 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, but there is a high to likely (50-60 percent) chance that SCA conditions due to a mix of wind and seas will linger into Wednesday night. 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, there is a moderate (30-40 percent) chance of SCA level winds this morning, increasing to a likely to imminent (60-90 percent) chance 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.

BEACHES

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.

LOX WATCHES/WARNINGS/ADVISORIES

CA...Wind Advisory remains in effect from 1 PM this afternoon to 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 87-340-346-354-362-366. (See LAXCFWLOX). Wind Advisory in effect from 3 PM this afternoon to 4 AM PST Wednesday for zones 340>343-346>349. (See LAXNPWLOX). High Surf Advisory in effect from midnight tonight to 9 PM PST Wednesday for zones 349-350. (See LAXCFWLOX). PZ...Small Craft Advisory in effect until noon PST today for zones 645-670-673. (See LAXMWWLOX). Gale Warning in effect from noon today to 3 AM PST Wednesday for zones 645-670-673. (See LAXMWWLOX). Small Craft Advisory in effect from noon today to 3 AM PST Wednesday for zone 650. (See LAXMWWLOX). Small Craft Advisory in effect from 3 PM this afternoon to 3 AM PST Wednesday for zone 655. (See LAXMWWLOX). Small Craft Advisory in effect from 9 AM this morning to 3 PM PST Wednesday for zone 676. (See LAXMWWLOX).