858
FXUS66 KLOX 091750
AFDLOX

Area Forecast Discussion...UPDATED
National Weather Service Los Angeles/Oxnard CA
1050 AM PDT Mon Mar 9 2026

.SYNOPSIS...09/235 AM.

Much cooler conditions are expected today as a coastal eddy
brings southeast flow to the area. The cooling trend will
continue into Tuesday, with another warm up expected to start on
Wednesday, lasting through at least Friday and possibly into next
week.

&&

.SHORT TERM (TDY-WED)...09/921 AM.

***UPDATE***

No significant changes in forecast thoughts.

Temperature trends were 10 to 20 degrees cooler than this time
yesterday for many coasts and coastal valleys this morning, on
track with the advertised major cool down today. The strong
southerly surge associated with this will probably lead to a slow
to no clearing of low clouds and fog across the Central Coast with
pockets of low clouds potentially developing across south facing
foothills further south at times through the day.

The cool down will be brief as heat is still expected to build
Wednesday and peak for coastal and coastal valley areas Thursday
and Friday when we may need a Heat Advisory. We may be talking
about heat for some time well into next week as a stubborn ridge
will likely become anchored over the region.

***From Previous Discussion***

Today will be much less windy and much cooler than Sunday. A large
554 dam upper low is spinning well south of San Diego and is
bringing some showers and isolated TSTMs to southern San Diego
County. Further north it is bringing some easterly winds to
southern LA county. There is a large mass of low clouds to the
west of the Central Coast and some beaches there may have low
clouds this morning. An eddy may bring some clouds to the LA south
coast as well. The gradients will actually be onshore this
morning and will turn moderately onshore in the afternoon. This
will bring an earlier and stronger sea breeze to the area. Hgts
will only be around 570 dam and this along with sea breeze will
contribute to a 10 to 15 degree cooling trend across the csts and
vlys. The lack of cool air advection from the San Joaquin Vly will
allow for a couple degrees of warming across the far interior.

The onshore flow peaks on Tuesday along with a decent eddy. This
should create a deep marine layer cloud deck that will cover the
coasts and many of the vlys. Its likely that low clouds will also
move over the interior of SLO county. Tuesday will be the coolest
day of the next 7. Look for 3 to 5 degrees of additional cooling.
This will bring max temps down to 60s and lower 70s across the
csts and vlys. These max temps are a few degrees blo normal. The
interior, however, will end up mostly in the lower 70s, which is 4
to 8 degrees over normal.

Just as fast as it cooled down it will warm up again on Wednesday.
A large E pac high will set up and a ridge will extend into Srn
CA. More importantly sfc high pressure will move back into the
Great Basin and will set up another round of offshore flow (this
time it will be more northerly). The offshore push should limit
the marine layer clouds to only the LA south coast. It will also
bring some northerly winds to the I-5 corridor and Santa Ynez
range. Hgts will increase to about 582 dam and this increase
along with the switch to offshore flow will bring 8 to 12 degrees
of warming to the area (4 to 8 degrees for the far interior). Look
for max temps in the 70s across the csts and lower to mid 80s in
the vlys.

.LONG TERM (THU-SUN)...09/235 AM.

The warm up really kicks into gear on Thursday. Offshore flow
peaks (about 2 mb from the east and 6 mb from the north). Hgts
jump to 588 dam as the ridge strengthens. These two items under
sunny skies will create 4 to 12 degrees of warming. Max temps
will be in the mid and upper 70s at the beaches, the 80s across
the rest of the csts, and upper 80s to lower 90s for the vlys.
These max temps are 15 to 25 degrees over normal. There is a
slight risk that the temps will be a tad warmer and will reach
heat advisory levels. The strong north flow will bring gusty near
advisory level winds to the I-5 corridor as well as the Santa
Ynez Range and SBA south coast.

The offshore flow weakens some on Friday - enough to lower the
morning offshore winds some, but not enough to affect temps, which
will end up very close to Thrusday`s very warm values.

Over the weekend the ridge will break down while the offshore
flow from the north will weaken and the onshore push to the east
will increase. Look for a couple of degrees of cooling each day with
max temps remaining well above normal with moderate heat impacts
potentially continuing through the weekend and even into next week
away from the coast.

Both AI-EC and AI-GFS are dry through the 22nd of the month. The
AI-GFS is dry on the 23rd but the AI-EC does bring rain to the
area on the 23rd.

&&

.AVIATION...09/1747Z.

At 1710Z, the marine layer depth was around 2800 feet deep at
KLAX. The top of the marine inversion was near 4900 feet with a
temperature around 10 degrees Celsius.

High to moderate confidence in VFR TAFs through this afternoon.
Low confidence in min flight cats and timing of marine layer
return. There is a 30% chance for VLIFR to LIFR conds at KPRB,
KSBP, and KSMX once cigs arrive tonight. Otherwise, min flight
cats may be off at one at any site. Arrival of cigs may be off +/-
4 hours.

Moderate confidence in winds, although there is a chance winds
are 5-10 kt stronger at times as winds will rapidly shift to
onshore later today.

KLAX...High confidence in VFR TAF through at least 00Z. Then high
confidence in cigs returning tonight, but low confidence when (+/-
4 hours from TAF). There is a 50% chance for IFR conds when cigs
are present. Any east wind component is expected to remain below
6-8 kt.

KBUR...High confidence in VFR TAF through at least 06Z. 30% chance
for no cigs tonight. Timing of arrival may be off +/- 4 hours,
and 40% chance for LIFR conds, 10% chance for VLIFR.

&&

.MARINE...09/822 AM.

Inside the southern California bight, marginal SCA southeast to
east winds will occur, especially from the San Pedro Channel into
the Anacapa Passage and the Santa Barbara Channel through this
afternoon. Then, winds and seas should remain below SCA level
through the period, except for a moderate (30-40 percent) chance
of SCA level west to northwest winds developing across the Santa
Monica Bay and into the San Pedro Channel on Wednesday afternoon
and evening.

For the waters southwest through northwest of the Channel Islands
and the nearshore waters along the Central Coast, marginal SCA
level winds will occur beyond 30 NM offshore of the Central Coast
to around Point Conception and south to San Nicolas Island
through early Thursday morning. More widespread SCA conditions
will develop from each afternoon and evening with a moderate to
high (30-50 percent) chance of affecting the nearshore waters
along the Central Coast, highest Tuesday afternoon and evening.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...Small Craft Advisory in effect until 3 PM PDT this afternoon
      for zones 650-655. (See LAXMWWLOX).
     Small Craft Advisory in effect until 3 AM PDT Thursday for
      zones 670-673. (See LAXMWWLOX).
     Small Craft Advisory in effect until 3 AM PDT Tuesday for
      zone 676. (See LAXMWWLOX).

&&

$$

PUBLIC...RM/Rorke
AVIATION...BL
MARINE...Hall/BL
SYNOPSIS...RM/Gomberg/CC

weather.gov/losangeles

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

NWS Los Angeles (LOX) Office