-- Discussion containing changed information from previous version are highlighted. --
997
FXUS66 KLOX 061611
AFDLOX

Area Forecast Discussion
National Weather Service Los Angeles/Oxnard CA
911 AM PDT Mon May 6 2024

.SYNOPSIS...06/426 AM.

A warming trend will establish through Wednesday as area sits
between high pressure to the west and a trough to the east. Gusty
northerly winds are expected at times, especially in the
mountains and in southern Santa Barbara County. A return of low
clouds and fog is expected through the week, possibly extending
into the valleys over the weekend.

&&

.SHORT TERM (TDY-WED)...06/858 AM.

***UPDATE***

The Frost Advisory has expired for the Cuyama Valley, Southern
Salinas Valley, and San Luis Obispo County Interior Valleys --
where diurnal heating is lowering the risk for frost. The forecast
has been updated to account for the expiration of the Frost
Advisory.

Otherwise, the forecast is well on-track, and no other changes
have been made to the ongoing forecast.

***From Previous Discussion***

The satellite imagery shows the region sitting in zonal flow
between an upper-level ridge of high pressure building into the
eastern Pacific Ocean and an upper-level trough over the northern
Intermountain Region. Clearer skies and less wind across the area
is setting up for a cool start to a May morning. Some wind
sheltered areas are dipping down to the mid 30s to lower 40s to
start today. With several hours until daybreak, a frost advisory
was added for the coldest areas in the northern interior valleys
through 8 am PDT this morning.

A northerly surface pressure gradient remains across the area in
the wake of yesterday`s cold front. The gradient has relaxed some
this morning, and some the wind advisories have been allowed to
expire. Winds are still remaining just strong enough through the
Interstate 5 Corridor this morning to keep the wind advisory in
place. Some weakening of the winds will continue through this
morning, then the gradient will tighten again this afternoon into
this evening. A wind advisory was extended for the Interstate 5
Corridor through 3 am PDT Tuesday, and reissued for southwestern
Santa Barbara County from 4 pm PDT this afternoon through 3 am PDT
Tuesday morning. There is a chance that the southeastern portion
of Santa Barbara County could see some another round of gusty
winds late tonight, but the chances looks less at this time.
Surface pressure gradients, local 3-km WRF, and EPS ensemble
members all indicate gusty northerly winds lingering across
southern Santa Barbara County and into the Interstate 5 Corridor
again Tuesday night and into Wednesday morning, so there will
likely be another round of wind advisories across the same areas.

With the ridge aloft to the west of the area, a warming trend will
take shape over the coming days with mostly sunny skies continuing.
Temperatures will warm to near to slightly above normal for most
areas on Tuesday and above normal on Wednesday. Marine layer
induced stratus clouds will likely be kept a bay (and very patchy
at best) today due to a weaker marine inversion, but low clouds
and fog could make a patchy appearance on Tuesday morning across
the South Coast of Los Angeles County. The chances for low clouds
and fog will increase through the week with the best chance for
any low clouds and fog in the short term on Tuesday night and into
Wednesday morning across the Los Angeles County coast and
possibly extending into the Ventura County beaches.

.LONG TERM (THU-SUN)...06/435 AM.

There is still a good amount of uncertainty in the long term
period. Models are struggling to handle a retrograding upper-
level trough of low pressure late in the week. The forecast
ensembles are still trending higher with temperatures away from
the coast while leveling off the warming trend along the coastal
sections toward the weekend. There are still about a fifth of the
solution going warmer for late week at the coast, but most trend
cooler with increasing cloud cover means. Interior portions of the
area have a good chance of seeing a steady warming trend through
the week. For the current time, temperatures go with NBM values
and moderate the warming trend toward at the coast into the
weekend, while the forecast reintroduces a mention of low clouds
and fog over the weekend.

&&

.AVIATION...06/1209Z.

At 12Z at KLAX, there was no marine layer or marine inversion.

Except for patchy low clouds across southern/eastern L.A. County
thru mid morning with local IFR conds, VFR conds are expected thru
early tonight, with some high clouds. Some low clouds with low
MVFR or IFR cigs may form in southern L.A. County and southern
portions of the Central Coast/Santa Ynez Valley late tonight.

Gusty NW winds will affect the I-5 Corridor and southwestern SBA
County thru late tonight, with some LLWS and turbulence likely.

KLAX...Moderate confidence in TAF. While VFR conditions are most
likely to continue thru the period, there is a 20-30% chance of
low MVFR to IFR cigs from 11Z-17Z Tue. There is a 30% chance of
an E wind component of 7-8 kt thru 16Z today, and 09Z-15Z Mon.

KBUR...High confidence in TAF with VFR conds expected thru the pd.

&&

.MARINE...
-- Changed Discussion --
06/908 AM.

Forecast on track this morning with no significant changes.

In the Outer Waters, moderate to high confidence in the forecast.
In the southern two zones (PZZ673/676), winds will increase to
gale force by afternoon, then will continue thru late tonight.
Gale force winds are likely again Tue afternoon into Tue night
(70% chance). Otherwise, Small Craft Advisory (SCA) level winds
and seas are expected thru late Wed night. In the northern zone
(PZZ670), SCA conditions are likely thru Wed night. There is a
50-60% chance of gale force winds Tue afternoon into Tue night.
SCA conds are not expected in the outer waters Thu thru Fri.

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 tonight thru Wed morning even after the winds decrease.
SCA cond are not expected Thu thru Fri.

In the Inner Waters S of Pt. Conception, moderate confidence in the
forecast. Expect SCA level winds across much of the SBA Channel
during the late afternoon thru late night hours today and Tue
(60-70% chance), with slightly stronger winds Tue. There is a 30%
chance of gales across western portions of the channel late Tue
afternoon into Tue night. In the southern inner waters, there is a
40% chance of SCA level winds across NW portions from Anacapa
Island to Malibu in the late afternoon/eve hours today and Tue.
-- End Changed Discussion --

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...Wind Advisory remains in effect from 4 PM this afternoon to 3
      AM PDT Tuesday for zones 349-351. (See LAXNPWLOX).
     Wind Advisory remains in effect until 3 AM PDT Tuesday for
      zones 377-378. (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 from 3 PM this afternoon to 3
      AM PDT Tuesday for zone 650. (See LAXMWWLOX).
     Small Craft Advisory in effect until 3 PM PDT Tuesday for
      zone 670. (See LAXMWWLOX).
     Gale Watch in effect from Tuesday afternoon through late
      Tuesday night for zone 670. (See LAXMWWLOX).
     Gale Warning in effect until 3 AM PDT Tuesday for zones
      673-676. (See LAXMWWLOX).

&&

$$

PUBLIC...Hall/Cohen
AVIATION...DB
MARINE...RM/DB
SYNOPSIS...Hall

weather.gov/losangeles

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