309
FXUS66 KLOX 030533
AFDLOX

Area Forecast Discussion
National Weather Service Los Angeles/Oxnard CA
1033 PM PDT Wed Apr 2 2025

.SYNOPSIS...02/1033 PM.

Generally dry weather through tonight except for lingering
showers over the interior and some light snow showers at times
near the Grapevine. Unsettled weather will return Thursday
afternoon with showers and thunderstorms possible and periods of
heavy rain near storms. Mostly dry weather on Friday but a 5 to 10
percent chance of showers and thunderstorms across eastern Los
Angeles County. Dry weather is expected over the weekend and all
of next week, with significant warming beginning Friday, and well
above normal temperatures next Tuesday and Wednesday with highs in
the 90s expected across the valleys.

&&

.SHORT TERM (WED-SAT)...02/1027 PM.

***UPDATE***

There`s been little change to the upper level pattern from
yesterday, as the area is still under a significant upper level
trough. Plenty of showers carried on throughout the day over San
Luis Obispo and Santa Barbara Counties, with a few afternoon
showers further south. Rainfall totals were generally light, but a
few areas that saw multiple rounds of showers surpassed 0.25
inches. Northwest winds were again quite gusty (generally around 35-50
mph), especially near the coasts, for the islands, and the Santa
Monica Mountains. Temperatures were a touch warmer than
yesterday, and the coasts and valleys south of Point Conception
saw widespread highs in the 60s to near 70 degrees.

Tonight, winds have decreased most areas, and showers persist over
interior San Luis Obispo County. Wind advisories were allowed to
expire, except for the Santa Ynez Range and western Santa Barbara
south coast where some gusty north winds persist through much of
tonight. This area may need more wind advisories for Thursday
night and Friday night. Other minor changes were made to the
forecast, expanding rain chances, but otherwise things look on
track for another round of convection with showers and possible
thunderstorms. This time, the focus will be over the Ventura and
Los Angeles Counties, extending into portions of Santa Barbara
County. Winds will be much lighter tomorrow, yet there will likely
be a few sub- advisory level breezy areas Thursday afternoon near
Point Conception and in the mountains.

***From Previous Discussion***

A large upper level trough continues to engulf most of the western
US with an upper low moving into AZ. Showers have been less
frequent today and mostly just near the Grapevine region with
moderate northwest flow pushing moisture up the north facing
slopes. Can`t rule out a stray shower through early evening but
best chances for those will remain over the mountains. Also
getting some fast moving showers developing across eastern SLO
County this afternoon and moving towards the Cuyama valley and
the northern Santa Barbara County mountains. Not expecting any
thunderstorms but some brief moderate showers are possible through
the early evening. Otherwise, mainly dry weather with gusty west
to northwest winds through this evening.

The trough will only move slightly east Thursday, and with some
additional upper level energy moving into southern California and
increasing instability, chances for showers and even some
thunderstorms are much higher tomorrow than today. Hi res models
really focus the precip over the Transverse range through the San
Gabriel Mountains, and then spilling down into the valleys and
possibly some of the coastal areas. Morning conditions will
generally be clear across the area but will quickly cloud over in
the afternoon with showers developing. Hourly rain rates in the
heaviest storms could reach a half inch, though in most cases
storms will only last 20-30 minutes over any one location as the
steering flow will be towards the southeast at around 30kt. Snow
levels are expected to stay above 5000 feet so no additional snow
expected on Interstate 5 but possibly an inch or two at higher
elevations.

The trough will finally be exiting the area Friday, but there`s
still some lingering upper level energy coming through during the
afternoon. However, moisture drops off and most of the instability
is farther east and south. Have left rain chances out for now but
will re-evaluate this with the hi res models tomorrow.

Dry and warmer weather expected Saturday with highs 4-8 degrees
warmer than Friday

.LONG TERM (SUN-WED)...02/158 PM.

Next week looks quite warm, especially inland and warmest on
Wednesday. A fast moving ridge moves through the area over the
weekend but gets knocked down Monday as an upper low moves into
the Pac NW. So after a couple days of warming temperatures look
for Monday to a little cooler, but still a few degrees above
normal in most areas.

A stronger high pressure ridge returns Tuesday and especially
Wednesday. With models also showing gradients either near neutral
or slightly offshore, temperatures across the interior coastal
plain and especially the valleys will warm up several more
degrees, likely reaching the at least the mid 90s for the warmest
valleys, with a around a 5-10% chance of Woodland Hills reaching
100.

&&

.AVIATION...03/0526Z.

At 0421Z at KLAX, there was a weak surface inversion to 1100 feet
with a temperature of 13 C.

High confidence in TAFs. There is a 10-20% chance for
thunderstorms to impact the mountains and valleys in eastern VTA
County and LA county after 18Z through 06Z. Any thunderstorms
could produce gusty and erratic winds, +RA, low visibilities, and
lightning.

KLAX...High confidence in TAF. There is less than a 10% chance
for thunderstorms to develop over the terminal from 18Z through
06Z. There is a 40% chance of an east wind component reaching 8 kt
between 12Z and 18Z.

KBUR...High confidence in TAF. There is a 15% chance for
thunderstorms to develop over the terminal from 18Z through 06Z.

&&

.MARINE...02/1018 PM.

Moderate to high confidence in the current forecast. Winds will
likely be at or near GALE force levels through late tonight across
the southern outer waters and the inner waters south of Point
Conception, with local gusts to 35 kt elsewhere. Steep and
hazardous seas will continue across all the waters through
Thursday morning.

Then, there is a 60-80 percent chance Small Craft Advisory (SCA)
conds continue through at least Friday evening across most of the
waters, except for a 30-50 percent chance for eastern Santa
Barbara Channel and the southern inner waters off the LA and OC
coasts Thursday afternoon and evening. A lull in SCA conds may
occur Friday morning, so currently holding off on extending the
current SCA all the way through Friday night, but moderate to
high confidence that SCA level winds will return Friday afternoon
through late night.

Winds will retreat below SCA levels late Friday night through
Saturday, with a 20-30 percent chance of SCA winds returning
Saturday afternoon into the evening, and a 40-50 percent chance
for Sunday afternoon through evening. Higher chances exist for SCA
conds early next week.

Dense fog may develop this upcoming weekend, especially in the
evening to morning hours, in response to a ridge building over
the region.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...Wind Advisory now in effect until 3 AM PDT Thursday for zones
      349-351-352. (See LAXNPWLOX).
     High Surf Advisory in effect from 3 AM to 4 AM PDT Thursday
      for zones 354-362-366. (See LAXCFWLOX).
PZ...Small Craft Advisory in effect until 3 AM PDT Thursday for
      zone 645. (See LAXMWWLOX).
     Gale Warning in effect until 3 AM PDT Thursday for zones
      650-655-676. (See LAXMWWLOX).
     Small Craft Advisory in effect until 3 AM PDT Friday for
      zones 670-673. (See LAXMWWLOX).

&&

$$

PUBLIC...Phillips/MW
AVIATION...Lewis
MARINE...Lewis
SYNOPSIS...Phillips/MW

weather.gov/losangeles

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