531
FXUS66 KLOX 081802
AFDLOX

Area Forecast Discussion...UPDATED
National Weather Service Los Angeles/Oxnard CA
1002 AM PST Wed Jan 8 2025

.SYNOPSIS...08/112 AM.

Widespread damaging north to northeast winds and extreme fire
weather conditions will continue through mid afternoon. Downed
trees and power lines, power outages, hazardous driving conditions,
increased traffic, and airport delays should be expected across
the Southland. Any wildfires that start will likely spread
rapidly with extreme fire behavior. Otherwise, dry conditions are
expected with warmer conditions to develop for late week.

&&

.SHORT TERM (TDY-FRI)...08/259 AM.

The high speed river of air remains over LA County this morning
and is fueling a widespread major wind event. The core of this low
level jet will slowly move southward during the day and this will
cause the winds over LA to slowly decrease. Since the wind speeds
are so high now (mtn gusts 70 to 90 mph) the slow decrease will
not bring the winds down to below warning levels until early
evening. There will, however, be a fairly notable drop off in
wind speeds late this morning.

Please the the produce LAXNPWLOX for all of the information about
the current slate of wind warnings and advisories. Please see the
fire weather discussion below for information on all of the fire
weather danger.

The offshore push from the north is decreasing, while the offshore
push from the east is increasing. These two things along with a
slight tilt to the NE in the upper level winds will turn the winds
a little more to the northeast. This will shut off the winds in a
few places, but turn them on in areas that have been fairly calm.
Its likely that many areas in western VTA county will see stronger
winds this morning. It is unlikely, however, that this switch
will affect the winds at the Eaton or Palisades fires.

After ydy`s huge surge of cold air from the interior, which
cooled the entire area despite the offshore, max temps today will
warm esp in the inland areas.

The offshore push on Thursday is about half of what it is today.
Additionally the upper support will also be much weaker. As a
result the winds will be weaker. At this time it looks like the
only advisory level winds will be in the LA and eastern VTA mtns.
Slightly higher hgts and much less cold air advection will bring 2
to 5 degrees of warming to most areas.

Unfortunately it looks like another Santa Ana is on tap for
Friday. The offshore push from the east will increase to 6 or 7
mbs and the NE upper support will increase. This will be a more
typical Santa Ana with predominantly NE winds focused along the
typical Santa Ana wind corridor from the Santa Clarita Vly to
Point Mugu. Wind advisories are likely in this area from early
morning to early afternoon. The downsloping winds will also reduce
the humidities and increase the fire danger.

One last detail...Overnight lows will likely be very chilly in the
wind-sheltered areas the next couple of nights.

Residents across Southern California are urged to remain vigilant
and monitor the latest forecasts. There is high confidence in
strong offshore winds with the potential to be the strongest wind
event of the season, especially for the Southland valleys. Trees,
large tree branches, and power lines may be downed by the wind
next week. Residents living the near the foothills and mountains
are advised to review the Ready,Set,Go! fire plan. Most residents
should be in the Set stage and being prepared to go in the event
of the fire evacuation.

.LONG TERM (SAT-TUE)...08/112 AM.

Both the GFS and EC deterministic mdls as well as the ensemble
means are in good agreement through Sunday evening. From Monday
and on the mdls and ensembles diverge leading to less confidence
for the Mon/Tue forecast.

Onshore flow finally returns on Saturday and while there will be
some weak northerly winds across the interior the csts/vlys will
see a welcome return of the seabreeze. Dry NW flow aloft will
prevail. Hgts will drop to 569 dam. Max temps will drop 4 to 8
degrees (xcp across the Antelope Vly where there will be little
change) under sunny skies. Max temps will end up mostly in the
60s.

On Sunday the NW upper flow begins to kink a little as a small
impulse ripples into NV. Unfortunately sfc high pressure building
into the Great Basin will bring another round of Santa Ana winds.
Right now without any upper support it is likely that the wind
gusts will be just under advisory levels. Max temps will change
little everywhere except in the Antelope Vly where there will be
about 4 degrees of cooling.

The trof will continue down the CA/NV border and will elongate
into Srn CA on Monday morning. From then on the exact upper
pattern is a tough call with GFS keeping a weak trof over Srn CA.
The EC on the other hand develops a full blown cut off low and
moves it over eastern Pacific. Looking at all of the ensemble
members there is a chance of a moderate offshore event on either
one (but likely not both days).

&&

.AVIATION...08/1800Z.

At 18Z at KLAX, there was no marine layer nor an inversion.

Good confidence in VFR conds, except for local MVFR/IFR conds due
to smoke near any fires. Moderate confidence in wind forecast due
to rapid and frequent changes in wind speed.

***Aviators need to be aware that most of Los Angeles and Ventura
Counties will be affected by an unusually strong and dangerous
north to northeast wind event into this afternoon***

Winds will be gusty and erratic, with lulls between gusts, so
wind shift timing could be off by +/- 3 hours and off by +/- 30
degrees and wind speeds and as much as 20 kt at any one time.

Widespread mdt to strong turbc is likely much of the time through
early this afternoon, with occasional svr turbc and stg UDDF.
Turbulence will be most prevalent near the mountains, including
the Santa Monica Range, but is possible in coastal areas as well.

There is currently smoke being observed at KSMO, Malibu and the
west side of Los Angeles from the Palisades fire, and in the San
Gabriel Valley from a fire near Altadena. Smoke is also being
produced by the Hurst Fire in the San Fernando Valley along I-5.
Any new fires today will produce smoke plumes, which may affect
airfields.

There could be blowing dust with MVFR vsbys at times for desert
airfields especially in the first half of the fcst pd (KPMD,
KWJF).

KLAX...High confidence in VFR conds through the period. Lower
confidence in wind fcst. Timing of winds changes could be off
by +/- 3 hours. Winds will be gusty and erratic and wind direction
will likely vary from 340 to 060 degrees thru 15Z. Wind speeds
may be off by 10-15 kt at any time. Moderate to strong LLWS and
turbulence will likely affect the airport at any time thru this
afternoon, but especially thru 21Z Wed. **SVR turbulence is
possible this morning.** There is a 20% chance of chc of a 25 kt
east wind component through at least 21Z, but the wind component
is likely to be more north or northeast than due east. There is a
30% chance winds do not shift from N-NE to west after 20Z
Thursday.

KBUR...High confidence in VFR conds through the period. Lower
confidence in wind fcst. Timing of wind changes could be off
by +/- 3 hours. Winds will be strong, gusty and erratic and
wind direction will likely vary from 330 to 070 degrees. Wind
speeds may be off by 10-20 kt at any time through 06Z. Moderate
to strong LLWS and turbulence will likely affect the airport at
any time thru this afternoon, but especially thru 00Z. SVR
turbulence is possible this morning. There is a 20% chance of
wind gusts to 45 kt at the airport thru 19Z.

&&

.MARINE...08/818 AM.

An exceptionally strong north-northeasterly wind event will
continue to impact portions of our coastal waters through
Wednesday. The strongest wind gusts and the worst sea conditions
are expected tonight through early Wednesday morning inside the
Southern California Bight. Mariners should expect DANGEROUS wind
and sea conditions across all of waters from off the coast of
Ventura County to Los Angeles and Orange Counties. This expansive
area includes all of PZZ655, much of PZZ676, and the
eastern/nearshore portions of the Santa Barbara Channel (Ventura
Harbor and Port Hueneme through Point Mugu), including the waters
around the Channel Islands and Catalina Island.

***Details***

For inner waters from Point Mugu to San Mateo Pt. CA including
Santa Catalina and Anacapa Islands (PZZ655), expect GALE Force N
to NE winds increasing to STORM Force winds early this morning
through this afternoon/eve with gusts up to 55 kt. Combined seas
will peak around 6 to 9 feet.

For inner waters along Ventura County Coast (PZZ650) and the outer
waters from Santa Cruz Island to San Clemente Island to 60 NM
offshore including San Nicolas and Santa Barbara Islands (PZZ676),
expect GALE force N to NE winds - 20 to 30 kts with gusts 35 to
45 kt through this afternoon/eve. Combined seas will peak around
7 to 10 feet for PZZ676 and 4 to 7 feet for PZZ650.

Please take this situation seriously, mariners should remain in
port, alter course, and/or secure the vessels as these
exceptionally dangerous sea conditions could capsize or damage
vessels of ALL sizes.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...High Wind Warning remains in effect until 6 PM PST this
      evening for zones 87-88-358-362-366>380-548. (See LAXNPWLOX).
     Wind Advisory remains in effect until 6 PM PST this evening
      for zones 350-352>357-381-382. (See LAXNPWLOX).
     Wind Advisory remains in effect until 2 PM PST this afternoon
      for zone 383. (See LAXNPWLOX).
     Red Flag Warning in effect until 6 PM PST Thursday for zones
      288-354-355-358-362-369>380-548. (See LAXRFWLOX).
     Fire Weather Watch in effect from Thursday evening through
      Friday afternoon for zones 288-358-362-369>376-378>380-548. (See LAXRFWLOX).
     Red Flag Warning in effect until 6 PM PST this evening for
      zones 352-353-367-381>383. (See LAXRFWLOX).
     Red Flag Warning in effect until 4 PM PST this afternoon for
      zones 366-368. (See LAXRFWLOX).
PZ...Gale Warning in effect until 3 PM PST this afternoon for zone
      650. (See LAXMWWLOX).
     Gale Warning in effect until 6 PM PST this evening for zone
      676. (See LAXMWWLOX).

&&

$$

PUBLIC...Rorke
AVIATION...Black
MARINE...Black/Smith
SYNOPSIS...Hall

weather.gov/losangeles

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