textproduct: Los Angeles

SYNOPSIS

13/1257 PM.

An offshore flow pattern beneath an upper-level ridge of high pressure will continue very warm and dry conditions across the region through the weekend. Gusty Santa Ana winds will continue through at least Thursday, strongest through and below passes and canyon during the late night and morning hours. The warmest day is likely to be Wednesday, then a slow and gradual cooling trend is expected through early next week.

LONG TERM (FRI-MON)

13/205 PM.

Another shot of cold air will push into the Mojave Desert between Thursday night and Friday. This shot of cold air will reinforce surface pressure gradients and offer up cooling of overnight low temperatures across the interior valleys and wind-sheltered locations. As the cold air mass arrives between Thursday night and Friday, a cooling trend will begin across most of the region for Friday. Due to downsloping taking place, it is possible that portions of the coast could see slight warming across the region.

An expanded set of wind advisory headlines should be needed between Thursday night and Friday as winds should tick up again. The cold shot of air will tighten offshore pressure gradients. EPS ensemble members suggest a tick up in the winds at KOXR and KCMA, but the wind support aloft does not change much.

A dry weather pattern is likely to persist through at least next Wednesday when the ensemble members advertise the first chance of rain across the region. A cooling trend beginning over the weekend should continue into early next week. A return of low clouds and fog seems likely Sunday or Monday.

AVIATION

13/1729Z.

At 1656Z at KLAX, there was no marine layer. There was a surfaced based inversion with a top at 1300 ft and a temperature of 20 C.

High confidence in CAVU TAFs. Moderate confidence in winds for KOXR, KCMA, KVNY, and KBUR (+/- 10 kt). High confidence elsewhere.

Gusty NE winds with LLWS and light to moderate turbulence is likely over and near mountainous terrain, focused across Los Angeles and Ventura counties.

KLAX...High confidence in CAVU TAF. No significant east wind component expected.

KBUR...High confidence in CAVU TAF. 10% chance for NE wind gusts up to 15 kts to surface through 22Z today, and again after 14/06Z. Light to moderate turbulence and LLWS likely through the period.

MARINE

13/130 PM.

Northeast winds will continue across nearshore portions of the Ventura, Los Angeles, and Orange, and San Luis Obispo county coasts and out to Santa Cruz Island through Saturday morning. These winds will create locally choppy seas, especially at their peak speeds in the early morning to early afternoon hours. Periods of 15-25 knot winds will occur across the aforementioned areas, with highest likelihood from Channel Islands Harbor through Malibu and out to Santa Cruz Island during the early morning through early afternoon hours from Wed night through Sat morning.

There is a very low chance (10%) for northeast wind gusts of 15-25 knots to impact Avalon and Two Harbors over the next few days, but chances increase slightly (25%) late Wed through Sat morning.

Elsewhere and otherwise conditions will remain unseasonably mild into next week. Seas across the Outer Waters will continue to lower through tonight.

LOX WATCHES/WARNINGS/ADVISORIES

CA...Wind Advisory remains in effect until 2 PM PST Wednesday for zones 88-355-358-362-369-371-374>376-378>380. (See LAXNPWLOX). Wind Advisory in effect until 2 PM PST Wednesday for zones 355-362. (See LAXNPWLOX). PZ...NONE.