Del Sur, California Weather Forecast Discussion

275
FXUS66 KLOX 301733
AFDLOX
Area Forecast Discussion...UPDATED
National Weather Service Los Angeles/Oxnard CA
1033 AM PDT Tue Sep 30 2025
UPDATED AVIATION DISCUSSION
.SYNOPSIS...30/1200 AM.
A series of weak disturbances will keep a persistent night through
morning low clouds pattern going across the coasts and lower vlys
through the week. Skies, otherwise, will be mostly clear. Afternoon
high temperatures will continue to run below normal.
&&
.SHORT TERM (TDY-THU)...30/912 AM.
***UPDATE***
There was unorganized marine layer cloud cover this morning, with
several coast and vly areas under mostly sunny skies this morning
while other areas are cloud-covered. The clouds are expected to
thin out and dissipate for many areas as the day progresses.
Otherwise, a rather quiet day weatherwise across SW CA today.
Breezy to locally gusty S to W onshore winds will prevail across
the region thru the afternoon. Temps are forecast to be about 3-8
deg below normal across the region today. Highs will range from
the 60s at the beaches to lower to mid 70s over the inland coast,
and from the mid 70s to around 80 for the vlys to lower mtns and
deserts.
***From Previous Discussion***
A weak trof is just exiting the area. It did not bring any rain to
the area but it did lift the marine layer to 4000 plus feet. A
large strata-cu layer covers a large portion of the forecast area
including the interior and lower mtn elevations. Some cool air and
mixing coming in behind the front will allow for decent clearing
this afternoon. Max temps will rise 3 to 6 degrees across SLO and
most of SBA county today as that area will see much more sunshine
that it did ydy. LA/VTA counties as well as the SBA south coast
will cool due to the deeper marine layer and lingering strata-cu
layer. Max temps everywhere will end up 4 to 8 degrees blo normal.
NW winds behind the trof will generate some gusty sundowner winds
this evening while there will be some isolated advisory level
gusts they will not be widespread enough for an advisory.
Fairly flat flow with an embedded dying trof will move over the
area on Wednesday. It will not bring too much weather. Look for
the marine layer will not be as deep as today but many vlys will
still see some morning low clouds. Slightly higher hgts and more
sunshine will bring 2 to 4 degrees of warming to most areas. Max
temps will remain blo normal.
A little less morning low clouds on tap for Thursday as the marine
layer continues to shrink and offshore flow across srn SBA county
combine to limit low clouds to the VTA/LA csts as well as the
Central Coast/Santa Ynez Vly. Less marine layer, more sunshine and
weaker onshore flow will all contribute to a 2 to 4 degree warming
trend. This will bring max temps up to within 1 to 3 degrees of
normal but still below.
.LONG TERM (FRI-MON)...30/1210 AM.
There is good agreement within the mdls and the ensembles about
the general pattern for the long term. It is a rather unusual one
for this time of the year. On Friday an upper low will swing
through the nrn portion of the state. In its wake, a long wave pos
tilt trof will drape over the state. Then on Monday a new upper
low will pinch off at the base of the trof and swing through the
center of the state.
The forecast remains dry as the preponderance of mdl solutions do
not have enough moisture to produce rain. Still the chc of rain is
not zero on Friday and Monday and is currently at 10 percent. If
either of the upper lows slows down over the waters or takes a
more westward track the chc of rain would be greater. The Central
Coast would likely be the area that would have a higher chc of
rain in these situations.
Much more confident in the night through morning coastal low cloud
pattern which will be enhanced by all of the cyclonic turning
aloft.
The onshore flow, lower than normal hgts and fairly deep marine
layer will all team up to continue below normal max temps on Fri
and Sat. The real cooling starts Sunday as hgts fall faster and by
Monday most max temps will end up 10 to 15 degrees blo normal.
Highs across the csts, vlys and even the Antelope Vly will be in
the 70s.
&&
.AVIATION...30/1731Z.
At 1648Z at KLAX, the marine layer was 5700 feet deep with an
inversion up to 5500 feet with a maximum temperature of 14 C.
High confidence in TAFs for KPMD and KWJF.
Moderate confidence in remaining TAFs. Mostly MVFR to VFR cigs
are expected tonight, although there is a 30% chance for IFR cigs
at KPRB, KSBP, and KSMX and a 15% chance at KBUR and KVNY.
Flight cat changes may be off +/- 3 hours, with lowest certainty
south of Point Conception.
KLAX...Moderate confidence in TAF. MVFR to VFR cigs may bounce
between SCT and BKN through this afternoon, then more uniform MVFR
cigs may arrive as early as 05Z or as late as 11Z. Minimum cig
height may be as low as OVC012, but high confidence in MVFR being
minimum flight cat. No significant east wind component expected.
KBUR...Moderate confidence in TAF. Flight cat changes may be off
+/- 3 hours. 15% chance for OVC007-010 cigs 10Z-16Z.
&&
.MARINE...30/818 AM.
This evening, moderate confidence in Small Craft Advisory level
winds occuring across the Santa Barbara Channel. Followed by a 60%
chance of SCA winds across the channel Wednesday and Thursday
afternoon/evening with a 40-50% chance of SCA level winds Tuesday
through Friday, mainly in the late afternoon and evening hours.
For the Outer Waters, moderate to high confidence in current
forecast. On Wednesday, there is a 30% chance of SCA level winds
across PZZ670 and a 60-70% chance across PZZ673/676. For Thursday
and Friday, there is a 60-80% chance of SCA level winds and seas
across all the Outer Waters. On Saturday, the chances of SCA level
winds continuing drops to 30-50%. For the Inner Waters north of
Point Conception, there is a 20-30% chance of SCA level winds
Wednesday afternoon and evening. For Thursday and Friday, there
is a 50-60% chance of SCA level winds, followed by a 30% chance of
Saturday.
Through Wednesday, a southerly swell of 3 to 4 feet will impact
the coastal waters and may produce issues for exposed south facing
harbors. Wednesday night through Saturday, a northwest swell will
build coastal waters, with seas peaking around 10 feet for the
outer waters and 6-8 feet across the inner waters.
&&
.BEACHES...30/208 AM.
A moderately-long period southerly swell will last into
Wednesday, generated by Hurricane Narda. Hazardous rip currents
and elevated surf are expected to continue for south- facing
beaches, especially across Los Angeles and Ventura Counties, as
well as Avila Beach and Port San Luis for the Central Coast.
Additionally, particularly vulnerable south-facing beaches may
see shallow coastal flooding over normally dry beach areas.
A HIGH SURF ADVISORY remains in effect for the Malibu Coast, with
surf of 4 to 7 feet again expected. A BEACH HAZARDS STATEMENT
remains in effect through Wednesday for all other south- facing
beaches along the Central Coast (4-7 feet, local sets to 8 feet),
Ventura and Los Angeles Counties (3-6 feet).
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
CA...Beach Hazards Statement in effect through Wednesday afternoon
      for zones 87-340-346-354-366. (See LAXCFWLOX).
     High Surf Advisory in effect until 6 PM PDT Wednesday for
      zone 362. (See LAXCFWLOX).
PZ...Small Craft Advisory in effect from 5 PM this afternoon to
      midnight PDT tonight for zone 650. (See LAXMWWLOX).
&&
$$
PUBLIC...Rorke/Sirard
AVIATION...Lewis
MARINE...Schoenfeld/Lewis
BEACHES...RAT/Schoenfeld
SYNOPSIS...30
weather.gov/losangeles
Experimental Graphical Hazardous Weather Outlook at:
https://www.weather.gov/erh/ghwo?wfo=lox

NWS LOX Office Area Forecast Discussion