Walnut, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

293
FXUS66 KLOX 190039
AFDLOX

Area Forecast Discussion...UPDATED
National Weather Service Los Angeles/Oxnard CA
539 PM PDT Fri Apr 18 2025

.SYNOPSIS...18/126 PM.

Skies will slowly clear today and a warming trend will develop
over the weekend bringing temperatures to within a few degrees of
normal Sunday and Monday. After that a slow cooling trend will
develop through the remainder of next week with increasing night
and morning low clouds and fog.

&&

.SHORT TERM (TDY-MON)...18/148 PM.

Clouds are very slowly clearing across the region today as the air
mass recovers from few days of deep marine layer and strong
onshore flow. Warmer air aloft is moving into the area today but
clouds are proving stubborn south of Pt Conception as weak
cyclonic flow is trapping moisture in the boundary layer below the
lee side of the Transverse range. As the marine inversion
continues to shrink and drier air aloft descends and punches
through the inversion this afternoon and evening clouds will
dissipate rapidly leading to mostly clear skies tonight into
Saturday.

Chamber of commerce weather is expected over the weekend into
Monday with plenty of sunshine and temperatures rising to within
a few degrees of normal. Low confidence on when or if low clouds
and fog will reform but clouds should just be morning feature at
most. Gradients are already trending weaker today and expect that
to really kick in tonight into early Saturday with a 4-5mb
offshore trend, leading to some areas of breezy northeast winds
across the LA Mountains and some of the higher valley areas
Saturday morning.

.LONG TERM (TUE-FRI)...18/158 PM.

Onshore flow begins its return as early as Sunday but especially
Monday as the next trough deepens along the West Coast. No
precipitation expected locally but temperatures will begin a slow
cooling trend that will continue through the week. Low clouds and
fog will return to coastal areas by Monday if not before and
eventually the valleys as cooling aloft deepens the marine
inversion. The increasing onshore flow will create increasing
west to southwest winds especially in the Antelope Valley. But
otherwise a fairly low impact period of weather with another long
stretch of below normal temperatures. Longer range models indicate
a continued cool pattern through next week and even into the last
week of April.

&&

.AVIATION...19/0035Z.

At 2353Z at KLAX, there was a weak inversion with a base near 3700
feet. The top of the inversion was near 4500 feet with a
temperature of 7 deg C.

High confidence in TAFs for KPMD and KWJF.

Moderate confidence in the Central Coast sites where MVFR conds
are expected overnight, but the onset time of CIGs may occur +/-
3 hours from TAF times. Otherwise, low confidence in the
remaining TAF sites where stratus CIGs may be periodic or short
lived, or may not occur at all. CIGs will most likely be MVFR
where they occur, but with a 20% chance of IFR CIGs. Timing of
CIGs is low confidence for all of these locations.

KLAX...Low to moderate confidence in the 00Z TAF. CIGs are
currently VFR, however there is a 30-40% chance of MVFR CIGs
developing overnight, with low confidence in timing if this should
occur. No significant east wind component expected.

KBUR...Low confidence in the 00Z TAF. Conds may bounce between
MVFR to VFR through 08Z. There is a 30% chance that MVFR conds
persist beyond 08Z, and a 20% chance of IFR to MVFR conds between
08Z and 15Z.

&&

.MARINE...18/141 PM.

For the Outer Waters, moderate to high confidence in current
forecast. There is a 30% chance for localized Small Craft
Advisory (SCA) level northwest wind gusts around Point Conception
down to the Northern Channel Islands and in the northern Outer
Waters this afternoon through early evening hours. Saturday
through Monday morning, there is a 20-30% chance for such winds
around Point Conception and the Channel Islands in the afternoon
and evening. Elsewhere, winds and seas are expected to remain sub
advisory through Monday morning. Then, Monday afternoon into at
least Tuesday, there is a 60-80% chance of SCA level winds.

For the Inner Waters north of Point Sal, moderate to high
confidence in current forecast. There is a 30% chance for
localized SCA level wind gusts this afternoon into the evening
near Pismo Beach. Saturday through Monday morning, high confidence
in winds and seas remaining below SCA levels. From Monday
afternoon through at least Tuesday, there is a 30-40% 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. Today through Tuesday, high
confidence in winds and seas remaining below SCA levels across
most areas. The only exception will be the western half of the
Santa Barbara Channel where there is a 30-50% of SCA level wind
gusts in the afternoon through evening hours.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...NONE.

&&

$$

PUBLIC...MW
AVIATION...Smith
MARINE...Lewis
SYNOPSIS...MW

weather.gov/losangeles

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