textproduct: Los Angeles

SYNOPSIS

03/856 AM.

Near to slightly above normal are temperatures expected through at least Saturday, except significant cooling in the mountains and interior areas starting Thursday. Strong and gusty winds expected across much of the area Wednesday night into Thursday morning. Strong Santa Ana winds possible over weekend with warming temperatures.

LONG TERM (FRI-MON)

03/150 AM.

There is finally better agreement amongst the Euro, GFS, and their AI versions. The upper level trough will dig to the southwest through Southern California on Friday. A low then cuts off from the main jet stream sometime Friday night into early Saturday, then the low will spin around, almost stationary off the coast of Baja California through Monday before ejecting to the east on Tuesday. Despite the better agreement amongst models, these cutoff lows are still difficult to forecast, thus there still exists a bit of uncertainty in the forecast.

Friday will kick off the first day of a moderate to strong Santa Ana wind event. Winds in the 35-50 mph range will be common across traditional Santa Ana Wind corridors beginning Friday morning. Upper level support will line up the best across the region on Saturday, which will help to elevate wind speeds and coverage, likely bringing solid advisory level winds down to the Ventura County and Malibu coasts. There is a 40% chance for damaging wind gusts (60-70 mph) across the Western San Gabriel Mountains, Santa Susana Mountains, I-5 Corridor, and Antelope Valley foothills, and a 20% chance for valleys and coasts. Some impacts may include downed trees and power outages and hazardous travel conditions due to crosswinds, especially for higher profile vehicles. After peaking in strength on Saturday, Santa Anas on Sunday will likely be similar in magnitude and coverage to Fridays event. Even weaker Santa Anas will occur Monday morning.

While this system is moisture starved as it cuts off and moves across SoCal initially, it will pull in some moisture while it meanders off the coast. As a result, there is a chance for this moisture to wrap around and create some very light rain across eastern LA County early next week.

Temperatures will be heavily influenced by the downsloping effects of the offshore flow. Warming will occur Friday through Sunday, with this weekend featuring highs in the 70s and 80s fairly widespread. Monday will feature a cool down, but that wont last long as riding will look to move in on the backside of the low.

AVIATION

03/1132Z.

At 0711Z over KLAX, the marine layer depth was 800 feet deep at KLAX. The top of the inversion was near 2100 feet with a temperature around 16 degrees Celsius.

Moderate to high confidence in TAFs. Chance for IFR cigs at KOXR (40%), KCMA (30%), KSBA (20%), and KSMX (20%) through 18Z. LLWS 5-10 knots possible at KSBP through 18Z. Lower confidence in arrival of cigs tomorrow night (+/- 4 hours), but all coastal sites are in play for LIFR-MVFR conds, highest cigs across coastal LA County.

KLAX...High confidence in TAF. 30% chance cigs BKN007-009 when cigs are present. Clearing time may be off by +/- 90 minutes. East winds 6-8 kt are likely through around 16Z, then are not expected to be significant thereafter.

KBUR...Moderate confidence in TAF. 20% chance for VFR conds to prevail. If cigs arrive, 30% chance for BKN002-004.

MARINE

03/902 AM.

Moderate to high confidence in the current forecast; seas could be up to 1-3 feet higher than forecast, especially between Wednesday and Friday.

Widespread SCA level winds are expected to rapidly increase again this afternoon. SCA level winds will affect the outer waters and the nearshore waters along the Central Coast through this afternoon. Then, widespread strong SCA and GALE conditions (winds and seas) will develop tonight through Friday.

An offshore flow pattern will set up Friday through Sunday, with a moderate (30 to 50 percent) chance of SCA levels winds inside the southern California bight and the nearshore waters along the Central Coast, with winds likely peaking on Saturday.

LOX WATCHES/WARNINGS/ADVISORIES

CA...NONE. PZ...Small Craft Advisory in effect until 3 PM PST Wednesday for zones 645-650. (See LAXMWWLOX). Gale Warning in effect from 3 PM Wednesday to 9 AM PST Thursday for zones 645-650. (See LAXMWWLOX). Small Craft Advisory in effect until 3 AM PST Wednesday for zones 670-673-676. (See LAXMWWLOX). Gale Warning in effect from 3 PM Wednesday to 3 AM PST Friday for zone 670. (See LAXMWWLOX). Gale Warning in effect from 3 AM Wednesday to 3 AM PST Friday for zones 673-676. (See LAXMWWLOX).