Atascadero, California Weather Forecast Discussion

978
FXUS66 KLOX 290609
AFDLOX
Area Forecast Discussion
National Weather Service Los Angeles/Oxnard CA
1109 PM PDT Sun Sep 28 2025
Updated Aviation Section
.SYNOPSIS...28/504 PM.
Cooler than normal conditions will persist through the week, but
temperatures should rise a little starting Wednesday. Night
through morning low clouds with patchy drizzle will be possible
across the coast and valleys through Tuesday.
&&
.SHORT TERM (SUN-WED)...28/658 PM.
***UPDATE***
Today was much quieter in regard to convection as expected. There
was a couple of heavy showers near Lockwood Valley and Reyes Peak
which produced beneficial rainfall with no major impacts. This
concludes the threat for convection through the foreseeable future.
A few stations are reporting wind speeds over 30 mph across the
Antelope Valley and adjacent foothills. These sub-advisory gusty
SW winds are expected to continue through this evening, and are
expected to return in similar magnitude perhaps a touch stronger
tomorrow afternoon.
The rather deep marine layer is still hanging far inland across
SLO and SBA counties - all the way to the La Panza Range and San
Rafael Range. Not expecting clearing for many locations along the
Central Coast due to onshore push & approaching trough. Elsewhere,
expecting a return of the marine layer overnight likely pushing
into the Santa Clarita Valley. Drizzle will be possible and even
likely along the Central Coast. Also, maximum Temperatures will
remain cool especially inland ranging 6-12 degrees below normal.
***From Previous Discussion***
Convection getting a much slower start today but can`t rule out an
isolated shower through the rest of the afternoon. Most likely
locations would be near Mt Pinos in the Ventura mountains and the
eastern San Gabriels. Chances for any thunderstorms have dropped
to 15% or less today and virtually no chance of any flooding.
The 4000 foot marine is having more success clearing today across
LA County but clouds are still pretty solid elsewhere. An
approaching trough will likely maintain the deep marine layer
pattern across the area through at least Tuesday with well below
normal temperatures. A weakening cold front associated with the
trough will create a little lift that could trigger another round
of drizzle each of the next couple mornings, especially along the
Central Coast. At one time models had been indicating as much as a
quarter inch of rain along the Central Coast with this system,
but subsequent models have weakened it quite a bit.
Heights will start rising Wednesday as the trough moves east and
high pressure starts to build around the 4 corners region.
Temperatures will still be below normal but warmer than they have
been with more sunshine and a shallower and earlier clearing
marine layer. Increasing northerly flow aloft following the
trough passage will likely generate some gusty Sundowner winds
southwest SB County Tuesday and Wednesday evenings, and possibly
around the Grapevine as well.
.LONG TERM (THU-SUN)...28/228 PM.
Pretty quiet period of weather later this week and over the
weekend. A majority of the models favor building high pressure
over the eastern Pacific, but with weak troughs dropping out of
Canada and into the Great Basin. This has the appearance of a
early Santa Ana pattern but not likely strong enough yet to
generate any strong winds. The latest GFS gradient actually shows
a light offshore flow developing this weekend but only about 1mb
offshore. Still enough to get some warming with highs climbing
back up to near normal this weekend.
&&
.AVIATION...29/0604Z.
At 06Z at KLAX, the marine layer was 2500 feet deep with a very
weak to no inversion.
High confidence in VFR with typical southwest winds at KPMD KWJF.
Moderate confidence in MVFR/VFR ceilings at KPRB KSMX KSBP, +/- 3
hours on clearing times. 20% chance of -DZ or -RA 10-16Z. Low
confidence at all other airports, with truly a 50/50 chance of
ceilings forming as early as 09Z or as late as 15Z. Moderate
confidence that if any ceilings do form they will be MVFR or VFR.
KLAX...Moderate confidence in VFR through at least 09Z. Low
confidence after that with a 50% chance of MVFR ceilings forming
and a 50% chance of not. High confidence in no significant east
winds.
KBUR...Moderate confidence in VFR conditions through Monday,
except for a 30% chance of MVFR ceilings at anytime 11-16Z.
&&
.MARINE...28/810 PM.
For the Outer Waters, moderate to high confidence in current
forecast. Today through Wednesday, high confidence in winds and
seas remaining below Small Craft Advisory (SCA) levels. However,
there is a moderate chance for SCA level winds south of Point
Conception Wednesday afternoon & evening. For Thursday and
Friday, there is a 50-80% chance of SCA level winds and seas.
For the Inner Waters north of Point Sal, moderate to high
confidence in current forecast. Today through Wednesday, high
confidence in winds and seas remaining below SCA levels. For
Thursday and Friday, there is a 40-50% chance of SCA level winds
in the afternoon and evening hours.
For the Inner Waters south of Point Conception, moderate to high
confidence in current forecast. For a majority of the southern
Inner Waters, high confidence in winds and seas remaining below
SCA levels through Friday. The only exception will be the western
half of the Santa Barbara Channel with a 40-60% chance of SCA
level winds on Wednesday through Friday, during the late afternoon
and evening hours.
Through this Wednesday, a southerly swell of 3 to 6 feet will
impact the coastal waters and may produce issues for exposed south
facing harbors.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
CA...Beach Hazards Statement in effect through Wednesday afternoon
      for zones 87-340-346-354-362-366. (See LAXCFWLOX).
PZ...NONE.
&&
$$
PUBLIC...MW/Black
AVIATION...RK
MARINE...RAT/Black
SYNOPSIS...MW/CC
weather.gov/losangeles
Experimental Graphical Hazardous Weather Outlook at:
https://www.weather.gov/erh/ghwo?wfo=lox

NWS LOX Office Area Forecast Discussion