Area Forecast Discussion
Issued by NWS Los Angeles, CA

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

000
FXUS66 KLOX 250001
AFDLOX

Area Forecast Discussion
National Weather Service Los Angeles/Oxnard CA
401 PM PST Fri Jan 24 2020

.SYNOPSIS...24/1244 PM.

High pressure will keep the area dry through Saturday, with above
normal temperatures expected. A very weak cold front will bring
clouds and a slight chance of rain for northern areas Sunday,
along with some cooler temperatures. Dry and breezy conditions are
expected Monday through Thursday.

&&

.SHORT TERM (TDY-MON)...24/131 PM.

Another fine winter day across southern California with highs 5-10
degrees above normal in many areas under sunny skies except for
some wispy high clouds. Winds are really the only impactful
weather concern over the next few days. A moderate northerly flow
has developed today that has created advisory level winds in parts
of srn SB County and locally breezy north to northeast winds
elsewhere. Some patchy dense fog is possible again tonight across
interior SLO County and also extreme southern LA County and
adjacent coastal waters.

A weak trough passing north of the area Saturday into
early Sunday will briefly turn gradients onshore leading to less
wind in most areas but cooler temps by a few degrees, especially
on Sunday as the marine layer rapidly spins up south of Pt
Conception.

However, by Sunday afternoon and night after the trough passes
northerly winds will be on the increase again, likely stronger
than tonight with advisory level winds in srn SB County and the I5
corridor and at least near advisory level winds in the Antelope
Valley. The trough itself should be dry for most areas but the
northerly flow behind it combined with lingering moisture in the
Central Valley could spawn a few light showers late Sunday.

As the flow turns northeast Monday downslope flow along with a
building ridge aloft will bring warmer temps back to the area once
again with highs bouncing back up 3-6 degrees from Sunday`s
levels.

.LONG TERM (TUE-FRI)...24/150 PM.

The ridge will keep the storm track well to the north and east
through the week and likely into the following week. Between that
and light to moderate offshore gradients temps will remain several
degrees above normal. Gusty north to northeast winds at times,
likely advisory levels in srn SB County and the I5 corridor. Winds
will get another boost Tuesday night into Wednesday following the
passage of an inside slider through the Great Basin and into
northern AZ/NM. During this time there may be some isolated
warning level wind gusts through the I5 corridor and srn SB
County and more widespread northerly winds into the coast/valleys
of LA/Ventura Counties.

The trough passage will result in some cooling for interior areas
due to the cold advection but continued downslope flow will offset
the cold advection aloft for coast/valleys and keep temps pretty
steady.

After the inside slider moves into nrn Mexico Thursday the models
have been in excellent agreement showing an even stronger ridge
developing later next week into next weekend. With offshore
gradients expected to continue through the period it`s looking
more and more likely we`ll see numerous 80+ degree temps by
Saturday and possibly as early as Friday. And models are still in
almost unanimous agreement that this dry pattern will persist
through at least the first full week in Feb.

&&

.AVIATION...25/0000Z.

At 2355Z at KLAX, the marine layer was around 400 ft deep. The
top of the inversion was near 900 ft at 17 degrees C.

High confidence in all 00Z TAFs except for KPRB, KLAX, and KLGB.
For KPRB, good confidence in IFR/LIFR conditions returning late
tonight, lower confidence on timing. For KLGB and surrounding
south bay areas, increasing confidence of IFR/LIFR cigs/vsbys
this evening, potentially becoming VLIFR overnight. There is a 40
percent chance of IFR/LIFR conditions at KLAX between 08z-16z.
There is a chance of moderate wind shear and turbulence through
tonight.

KLAX...High confidence in 00Z TAF through 08Z, then moderate
confidence. There is a 40% chance of LIFR to IFR conditions after
08Z. There is a 30% chance of moderate wind shear and turbulence
between 03Z and 07Z.

KBUR...High confidence in 00Z TAF. There is a 40% chance of
moderate wind shear and turbulence through 08Z.

&&

.MARINE...24/202 PM.

For the Outer Waters, high confidence in the current forecast. In
addition to the Small Craft Advisory (SCA) level northwest winds
currently impacting all the outer waters, hazardous seas will
build to at least 10 feet by this evening. A combination of SCA
level winds and seas are likely to continue through the forecast
period. There is a 50 percent chance of gale force winds Tuesday
and Wednesday.

For the Inner Waters north of Point Sal, moderate-to-high
confidence in the current forecast. There is a 40% chance that
marginal SCA level winds could develop this afternoon and evening,
but SCA level hazardous seas above 10 feet will be very likely by
late this evening. A brief break in SCA level winds and seas
could develop late Saturday night through Sunday morning, but
there is a 70% chance of SCA conditions Sunday afternoon through
Wednesday.

For the Inner Waters south of Point Conception, moderate-to-high
confidence in the current forecast. There is a 60% chance of SCA
level winds across the western portion of the Santa Barbara
Channel this afternoon and evening, and a SCA has been issued. There
is a 70% chance of SCA level west to northwest winds and SCA
level seas Sunday afternoon through Wednesday, mainly across
western portions.

&&

.BEACHES...24/152 PM.

A large, long-period northwest swell is expected to move into the
coastal waters this evening and last through at least Sunday
morning. A HIGH SURF ADVISORY will be in effect for all west-facing
beaches starting this evening for the Central Coast, tonight for
the Ventura and LA County Coast, and Saturday morning for the
Santa Barbara South Coast. There is a period on Sunday where surf
may drop below High Surf criteria, but another larger northwest
swell is expected to move into the waters Sunday evening and last
through early next week. Therefore there is a 40% chance that the
High Surf Advisory may need to be extended through Tuesday.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...High Surf Advisory in effect until 3 AM PST Sunday for zones
      34-35. (See LAXCFWLOX).
     Wind Advisory in effect until 3 AM PST Saturday for zones
      39-52. (See LAXNPWLOX).
     High Surf Advisory in effect from 6 AM Saturday to noon PST
      Sunday for zone 39. (See LAXCFWLOX).
     High Surf Advisory in effect from 10 PM this evening to noon
      PST Sunday for zones 40-41-87. (See LAXCFWLOX).
PZ...Small Craft Advisory in effect until 9 PM PST Saturday for
      zone 645. (See LAXMWWLOX).
     Small Craft Advisory in effect until 3 AM PST Saturday for
      zone 650. (See LAXMWWLOX).
     Small Craft Advisory in effect until 3 AM PST Monday for
      zones 670-673-676. (See LAXMWWLOX).

&&

.HAZARD POTENTIAL OUTLOOK (MON-FRI).

Gusty northerly winds are expected through at least Wednesday,
especially through the Santa Ynez Range and the Interstate 5
Corridor.

&&

$$

PUBLIC...MW
AVIATION...Gomberg
MARINE...Stewart
BEACHES...Stewart
SYNOPSIS...JLL/Phillips

weather.gov/losangeles


USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.