High Wind in California, January 21 to 22, 2022

Area Forecast Discussion
National Weather Service Los Angeles/Oxnard CA
200 PM PST Fri Jan 21 2022

.SYNOPSIS...21/151 PM.

Mostly clear skies and above average daytime temperatures will
continue through the weekend as offshore flow remains in place.
Strong and potentially damaging Santa Ana winds will develop
tonight and Saturday. Winds and offshore flow will gradually
weaken through Sunday, then a return to onshore flow is expected
early next week. A warming trend is expected for the latter half
of next week.

&&

.SHORT TERM (TDY-MON)...21/151 PM.

Santa Ana winds starting to increase across the area this
afternoon as an upper low continues its trek south to the lower
Colorado River Valley. Everything still looks on track for winds
peaking this evening into Saturday morning. Isolated gusts to
80mph still seem reasonable for parts of the western San Gabriels
and 55-65mph in higher parts of the eastern Ventura and Western
LA County Valleys. Gradients aren't particularly strong with this
event but the upper support is impressive with northeast winds in
the 850-900mb layer near 60kt and good cold advection. Since this
has better upper support the Santa Ana winds will be felt in more
areas than what is typical, including parts of the San Gabriel
Valley, the eastern San Fernando Valley, and even parts of the LA
Basin such as Long Beach and Palos Verdes. And the Edwards radar
is picking up some returns from what is likely blowing dust moving
into the Antelope Valley. As a result, wind advisories and high
wind warnings cover all of Ventura and LA Counties through
Saturday afternoon, at which time winds aloft and gradients
decrease quite a bit. Saturday evening there's a brief uptick in
winds aloft and it's likely that wind advisories will be needed in
more of the traditional Santa Ana prone areas through early
Sunday afternoon.

Temperatures will be a little trickier than usual given the strong
upper support and cold air advection. Downsloping winds will help
boost temps for coast and valleys but with the source air being so
cold it won't be quite as warm as with typical Santa Ana's.
Overnight temps will be quite cold in wind protected areas like
Ojai but moderated in windy areas.

Monday we'll see some cooling for coast/valleys with a light
onshore trend but warming across the interior as the air mass
aloft recovers from the departed upper low.

.LONG TERM (TUE-FRI)...21/158 PM.

Fairly quiet weather expected next week with no precipitation.
Offshore flow will continue to weaken Monday with cooling sea
breezes developing a little earlier than Sunday. But slight
warming still for interior areas. Models now in decent agreement
showing the next trough taking a more easterly track through the
Great Basin with minimal impacts locally. A few ensemble members
still show a slight bump in offshore winds Tue/Wed but most favor
a typical light wind regime with no other impacts. After that
strong high pressure will return over the west coast and bring a
warming trend to all areas. If the light offshore flow pattern on
both the GFS and EC develops as well we could see temperatures
back into the 80s for some areas late next week.

&&

.AVIATION...21/1829Z.

At 1756Z at KLAX, the marine layer was around 800 feet deep. The
top of the inversion was around 1200 ft at a temp of 14 C.

Low clouds may linger at KPRB through 20Z, otherwise high confidence
in VFR conditions for all TAFs through the period.

Moderate confidence in wind forecast, especially for LA and
Ventura County sites. N to NE winds will likely develop by 22Z-00Z
across inland areas then spread to the coast and strengthen
through the night into Saturday morning. Timing of wind changes
may be off by a few hours. There will be areas of LLWS, some
moderate to strong turbulence, and moderate to strong UDDF.

KLAX...High confidence in VFR conditions and moderate confidence
in wind. There is a 20-30% chance that northerly cross winds will
reach 30 kt between 03Z and 10Z Sat. There is a 20-30% chance of
an east wind component of 10-12 kt from 10Z-16Z Sat. There may be
some LLWS near the airport from 00Z-16Z Sat.

KBUR...High confidence in VFR conditions and moderate confidence
in wind. There is a 20-30% chance of N to NE wind gusts reaching
40-45 kt between 01Z and 12Z Sat.

&&

.MARINE...21/1251 PM.

NW winds from Point Conception to San Nicolas Island have been
gusting to 25 kt consistently the past few hours so went ahead and
issued a Small Craft Advisory. The SCA that was to be in effect at
7pm for the outer waters south of Point Conception was just
shifted to begin now instead. An SCA was added for the waters from
Point Conception to the Channel Islands through 9pm. These NW
winds will weaken later this evening as NE flow takes over. For
the inner waters along the Central Coast, there is 40% chance of
SCA level NE winds (from Santa Lucia winds) late tonight through
Saturday morning.

NE winds will be quick to develop late this afternoon or early
evening across the typical Santa Ana wind corridors from Ventura
to Santa Monica and through the San Pedro Channel. Gale Force
winds will be likely nearshore then rapidly extending out to at
least Anacapa and Santa Cruz Islands, as well as to Catalina
Island. Isolated gusts to 45-50 kt are possible especially closest
to shore late tonight through early Saturday. In between these
typical corridors across the waters south of Point Conception
strong SCA level NE to E winds will be likely extending out to San
Nicolas Island. Winds will slowly diminish Saturday afternoon,
but SCA level NE winds are likely again Saturday night through
Sunday morning from Ventura to Santa Monica and out to Anacapa and
Santa Cruz Islands.

Tonight and Saturday, strong northeast winds will likely affect
east-facing harbors including Avalon Harbor, Two Harbors, and
Smugglers Cove. These winds will generate short-period, wind-driven
seas and create significant hazards to mariners and property.
Please see the (LAXMWSLOX) for additional details.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...Wind Advisory in effect until 9 AM PST Saturday for zone 34. (See LAXNPWLOX).
     Wind Advisory in effect until 3 PM PST Saturday for zones
      40-41. (See LAXNPWLOX).
     High Wind Warning in effect until 3 PM PST Saturday for zones
      44>46-53-54-88-547. (See LAXNPWLOX).
     Wind Advisory in effect until midnight PST tonight for zone
      59. (See LAXNPWLOX).
PZ...Gale Warning in effect from 5 PM this afternoon to 3 PM PST
      Saturday for zones 650-655. (See LAXMWWLOX).
     Small Craft Advisory in effect until 9 PM PST this evening
      for zone 673. (See LAXMWWLOX).
     Small Craft Advisory in effect until 3 PM PST Saturday for
      zone 676. (See LAXMWWLOX).

&&

.HAZARD POTENTIAL OUTLOOK (MON-FRI).

No significant hazards expected.

&&

PUBLIC...MW
AVIATION...Stewart
MARINE...Stewart
SYNOPSIS...MW

weather.gov/losangeles

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