High Wind Warning 20, NWS Los Angeles, CA

Area Forecast Discussion
National Weather Service Los Angeles/Oxnard CA
151 PM PST Mon Nov 14 2022

.SYNOPSIS...14/227 AM.

It will be sunny today with below normal temperatures with light
offshore flow. Moderate to strong Santa Ana winds will bring
threats of wind damage and wildfire Tuesday through Thursday,
peaking Tuesday night through Wednesday. Warming conditions toward
the coast Wednesday and Thursday.

&&

.SHORT TERM (TDY-THU)...14/149 PM.

Overall, 12Z models in very good synoptic agreement through the
short term period. At upper levels, low just west of Monterey this
afternoon will work its way south along the coast, reaching
northern Baja Mexico by Wednesday afternoon. Near the surface,
offshore gradients will on the increase through Wednesday then
will diminish on Thursday.

With this synoptic pattern, high confidence in strong Santa Ana
winds developing across Ventura and Los Angeles counties. Timing
wise, northeast winds will "ramp up" during the day on Tuesday,
then peak late Tuesday night and Wednesday then diminish Wednesday
night and Thursday. Deterministic models indicate LAX-DAG gradient
peaking between -6.5 and -9.0 mb with 35-55 kt winds at 950/850 mb
levels. Various ensemble guidance (HREF, NBM, etc.) all support
the deterministic runs, indicating strong northeast winds across
Ventura/LA counties. Will upgrade HIGH WIND WATCH to a HIGH WIND
WARNING for many areas of Ventura and LA counties from Tuesday
evening through Wednesday evening. From Wednesday evening through
Thursday, the Santa Ana winds will be weaker as upper level
support and pressure gradients weaken, but still a good chance of
advisory-level winds continuing into Thursday afternoon.

For San Luis Obispo and Santa Barbara counties, the northeast
winds will be weaker as pressure gradients and upper level winds
are weaker and advisory-level winds are not anticipated. However,
the foothills and mountains will still see northeasterly winds
gusting 25-40 MPH Tuesday evening through Thursday afternoon
(especially the Santa Lucia Range). Please refer to LAXNPWLOX for
the latest details on the wind products.

As the offshore winds develop, temperatures will be on the
increase. On Tuesday, high temperatures will climb into the mid
60s to mid 70s, but will increase to the 70s by Wednesday, west
of the mountains.

.LONG TERM (FRI-MON)...14/149 PM.

For the extended, 12Z models continue to be in good synoptic
agreement. At upper levels, a couple of inside sliders will drop
across the Great Basin Friday through Monday. Near the surface,
offshore gradients will continue, peaking in strength on Saturday.

Forecast-wise, the main focus through the extended period will
continue to be winds. The inside sliders will continue to maintain
surface high pressure over the Great Basin, resulting in continued
offshore winds. At this time, pressure gradients peak on Saturday
and this should be the period of strongest winds. At this time,
looking at the models and their ensembles, it looks to be either a
sub-advisory (GFS) or low end advisory-level (ECMWF) event for
Saturday with sub-advisory offshore winds all areas Friday and
again Sunday/Monday.

Other than winds, nothing really too exciting expected in the
extended. Skies should remain mostly clear through Sunday, but
will turn partly cloudy on Monday as some high clouds drift across
the area. The persistent offshore flow should prevent any marine
layer stratus/fog from developing through the period. As for
temperatures, there will be some slight cooling Friday/Saturday
then near persistence temperatures Sunday/Monday.

&&

.AVIATION...14/1735Z.

At 1715Z at KLAX, there was no marine inversion nor a sfc based
inversion.

Good confidence in CAVU conds through the period.

KLAX...High confidence in CAVU TAF. There is a 30 percent chc of
a 7 kt east wind component after 10z.

KBUR...High confidence in CAVU TAF.

&&

.MARINE...14/146 PM.

No changes to the marine forecast in the morning update.

For the northern two outer waters zones (PZZ670/673), moderate
confidence in the forecast. Winds and seas are expected to remain
below Small Craft Advisory (SCA) levels thru Wed night, although
there is a 30% chance of SCA level N-NE winds late Tue night and
early Wed near the coast. There is a good chance of SCA level
winds Thu, then SCA winds are likely Fri.

In the southern outer water zone (PZZ676), moderate confidence in
the forecast. Winds are seas are expected to remain below SCA
level thru Tue evening. SCA level NE winds are possible late Tue
night (40% chance), and likely on Wed, along with steep NE wind
waves. There is a 30% chance of Gale force gusts Wed morning south
of Santa Cruz Island. Conds should be below SCA levels Wed night,
but SCA conds are likely again Thu thru Fri.

For the Inner Waters north of Point Sal, moderate confidence in
the forecast. SCA conds are not expected through Fri, except
there is a 30% chance of SCA level NE winds very late Tue night
and Wed morning.

For the Inner Waters south of Point Conception, moderate
confidence in current forecast. SCA conds are not expected
through Tue evening. NE winds will likely reach GALE WARNING
levels late Tue night and continue through Wed afternoon across
eastern portions of the SBA Channel and much of the southern inner
waters zone (PZZ655) including out to Catalina Island. A Gale
Warning has been issued for the inner waters south of Point
Conception.

This has the potential to be a significant and dangerous wind
event, and confidence in this is increasing. SCA conds are not
expected Wed night through Fri, although there could be local SCA
level N-NE wind gusts from Ventura to Malibu late Wed night and
Thu morning.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...High Wind Warning in effect from 7 PM Tuesday to 7 PM PST
      Wednesday for zones 53-54. (See LAXNPWLOX).
     High Wind Warning in effect from 10 PM Tuesday to 7 PM PST
      Wednesday for zones 88-354-355-358-359-362-363-547. (See LAXNPWLOX).
     Red Flag Warning in effect from 7 AM to 7 PM PST Wednesday
      for zones 254-288-354-355-358-359-362-363-547. (See LAXRFWLOX).
PZ...Gale Warning in effect from 10 PM Tuesday to 3 PM PST
      Wednesday for zones 650-655. (See LAXMWWLOX).

&&

PUBLIC...Thompson
AVIATION...Sweet/Rorke
MARINE...Sweet/DB
SYNOPSIS...RK

weather.gov/losangeles

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