086
FXUS66 KLOX 051315
AFDLOX

Area Forecast Discussion
National Weather Service Los Angeles/Oxnard CA
615 AM PDT Sun May 5 2024

.SYNOPSIS...05/511 AM.

A cold storm system will continue to exit the region today,
leaving cooler temperatures across the region, isolated to
scattered showers in the mountains, and gusty west to northwest
across portions of the area. Zonal flow aloft will establish
Monday and persist over the region into late week as an upper-
level ridge builds into the eastern Pacific Ocean and an upper-
level trough aloft digs into the Intermountain West and Great
Basin. A warming trend will develop into late week.

&&

.SHORT TERM (TDY-TUE)...05/511 AM.

The latest radar mosaic shows light precipitation continuing to
fall over Los Angeles County early this morning as a cold front
moves over the region. Steady precipitation will exit the area
towards dawn, and only isolated to scattered showers will become
confined to the mountains late this morning. Skies should clear
through the day, but a cold day for May is shaping up. There is a
low to moderate chance of record cool high temperatures being set
today, highest at a 40 percent chance for KPMD. The record daily
cold maximum temperatures for KPMD is 61 degrees set on this
calendar day in 1998. While coastal areas will be only about 3-8
degrees below normal for this time of year due to the typically
persistent marine influence in May, the valleys, mountains, and
desert are forecast to be 10-20 degrees below normal for
today. The exception to this will be across southern Santa
Barbara County where KSBA and the Santa Barbara area could be the
warmest spot in the area due to compressional heating taking place
with the northerly winds.

A northwest surface pressure gradient will develop through today
and gusty winds will increase across the area. The gradient
will tighten through this afternoon and evening and increase the
winds across the area. An ample west to northwest push will bring
advisory levels winds to the coastal sections, portions of the
coastal valleys, across the mountains, and down into the Antelope
Valley. Wind advisories remain in effect for much of the
Transverse Range and down into the southern Santa Barbara County
through late tonight. A wind advisory for the remaining coastal
sections and into the Santa Ynez Valley will go into effect at 10
am this morning. The wind advisory for the San Gabriel Mountains
and eastern Antelope Valley foothills was just allowed to expire,
but the advisory for the Antelope Valley and the adjacent western
foothills was extended into this evening. If traveling across the
area, be prepared for gusty cross winds, especially if driving
along Highway 1 and 101, through the San Marcos Pass on Highway
154 and Tejon Pass on Interstate 5, and out across the high desert
on Highway 14. Blowing dust may be a particular hazard at times
west of Highway 14.

Winds will start to diminish on Monday as the gradient relaxes.
Generally, clearing skies are expected tonight through Monday,
but there is a moderate chance of low clouds and fog returning to
the Los Angeles County coastal area and southern Salinas Valley
early Monday morning.

A zonal flow pattern will develop aloft between Monday and
Tuesday as ridging aloft will build into the eastern Pacific Ocean
and an upper-level trough digs into Intermountain West.

.LONG TERM (WED-SAT)...05/502 AM.

A warming trend continues into at least Wednesday and possibly
into late week. Forecast ensemble temperature means climbs
throughout the week, but there is quite a bit of spread across the
solutions with some uncertainties later in the week and next
weekend. The spread becomes much more significant as forecast gets
into Friday through next Sunday. The model solutions are
struggling with how to handle the ridge to the west and the trough
over the West, which could retrograde back as a cutoff low. The
spread gets as large as 20-30 degrees for all locations across the
region. For now, the forecast goes with NBM values.

Gusty northerly winds are likely to persist through the Interstate
5 Corridor and across southern Santa Barbara County during the
week.

&&

.AVIATION...05/1312Z.

At 12Z at KLAX, there was no marine layer nor inversion.

Lingering moisture will keep skies partly to mostly cloudy this
morning, especially away from the coast. Cigs will be mostly MVFR
in coastal areas, and IFR or lower in the foothills/mtns. Expect
skies to clear by afternoon, though some IFR-VLIFR cigs may linger
in the foothills. Skies should be mostly clear tonight, except for
possible stratus in the Salinas Vly and on the Central Coast with
IFR-VLIFR conds, and possible MVFR cigs in coastal L.A. County.
Gusty W to NW winds will affect much of the region thru this
evening with areas of LLWS, turbulence and mdt UDDF.

KLAX...Moderate confidence in TAF. There is a 20-30% chance of
MVFR cigs thru 17Z and again 10Z-16Z Mon. Gusty west winds are
expected later this morning thru this evening. There is a 20%
chance of northerly cross winds to 12-18 kt from 02Z-07Z, and
a a 20% chance of an E wind component of 7-8 kt 10Z-17Z Mon.

KBUR...Moderate confidence in TAF. There is a 20-30% chance of
MVFR cigs thru 17Z and again 10Z-16Z Mon. There is a 30% chance
of NW wind gusts to 25 kt from 16Z-02Z Mon.

&&

.MARINE...05/600 AM.

In the Outer Waters, moderate to high confidence in the forecast.
In the southern two zones (PZZ673/676), expect winds to increase
to gales (80% chance) this afternoon, then continue thru late
tonight. Otherwise and elsewhere, SCA level winds (and seas at
times) are expected thru Wed night, with a 40% chance of SCA conds
Thu. There is a 50% chance of gales Tue afternoon into Tue night.

For the Inner Waters N of Pt. Sal, moderate to high confidence in
the forecast. Thru Wed night, winds are expected to reach SCA
levels during the afternoon/eve hours. Seas may remain at or above
SCA levels Mon night thru Wed morning, even when the winds decrease.

In the Inner Waters S of Pt. Conception, moderate confidence in the
forecast. Expect SCA level winds to increase to gales this afternoon
into tonight across the SBA Channel, (70-80% chance), and from
Anacapa Island to Malibu (60% chance). Elsewhere, SCA conds are
expected thru late tonight. SCA conds are likely (70% chance) during
the late afternoon thru late night hours Mon and Tue, with a 30-40%
chance of SCA conds during these times in the eastern portion of
the SBA Channel and western portions of the southern inner waters.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...Wind Advisory remains in effect from 10 AM this morning to 9
      PM PDT this evening for zones
      87-340-341-346>348-354-355-362-366. (See LAXNPWLOX).
     Wind Advisory remains in effect until 3 AM PDT Monday for
      zones 349>353-376>378. (See LAXNPWLOX).
     Wind Advisory remains in effect until 9 PM PDT this evening
      for zones 381-383. (See LAXNPWLOX).
PZ...Small Craft Advisory in effect from 3 PM this afternoon to 9
      PM PDT this evening for zone 645. (See LAXMWWLOX).
     Small Craft Advisory in effect until 3 PM PDT this afternoon
      for zones 650-655-673-676. (See LAXMWWLOX).
     Gale Warning in effect from 3 PM this afternoon to 3 AM PDT
      Monday for zones 650-655-673-676. (See LAXMWWLOX).
     Small Craft Advisory in effect until 3 AM PDT Monday for zone
      670. (See LAXMWWLOX).

&&

$$

PUBLIC...Hall
AVIATION...DB
MARINE...DB
SYNOPSIS...Hall

weather.gov/losangeles

Experimental Graphical Hazardous Weather Outlook at:
https://www.weather.gov/erh/ghwo?wfo=lox