Stevenson Ranch, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

223
FXUS66 KLOX 050628
AFDLOX

Area Forecast Discussion...UPDATED
National Weather Service Los Angeles/Oxnard CA
1128 PM PDT Sun May 4 2025

.SYNOPSIS...04/748 PM.

Temperatures will remain several degrees below normal through mid
week with areas of night to morning low clouds and fog. Scattered
showers and isolated thunderstorms will be possible across inland
areas of Los Angeles and Ventura Counties Monday afternoon. A
warming trend is expected to begin Wednesday with above normal
temperatures inland and near normal temperatures near the coast.

&&

.SHORT TERM (SUN-WED)...04/827 PM.

An unseasonably cold upper level low pressure system centered
over southwest Arizona this evening will continue to shift
eastward overnight. This system brought some wrap around moisture
into the region earlier today, with mostly light rainfall
accumulations under a half inch. There was an active area of
thunderstorms near Saddleback Butte (northeast Antelope Valley)
this afternoon, but most of the convective activity remained
to the north and east of our forecast area. Current doppler
radar imagery continues to show some scattered shower activity
rotating into LA county and points eastward as of 830 pm this
evening. For the remainder of tonight, there will be a 20-30
percent chance of showers, mainly across interior LA
county. With the upper low shifting eastward, temperatures
aloft are starting to gradually warm, so atmosphere not
as unstable as earlier today. However, could not rue out
a stray thunderstorm across the Antelope Valley and
San Gabriel mountains, but the probability is now less than
10 percent.

Otherwise, there will be partly to mostly cloudy skies
across much of the remainder of our region. With residual
moisture and some daytime heating, there will be a 20 percent
chance of showers on Monday afternoon across interior LA/
Ventura counties. With parameters tomorrow not as unstable as
earlier this afternoon, the chance of thunderstorms in these
areas will remain less than 10 percent.

*** From previous discussion ***

Otherwise, a stubborn marine layer with tops around 5000 feet has
been slow to clear LA and eastern Ventura County. Northerly flow
around the upper low has managed to clear most areas to the west
but expect low clouds to linger in these same areas and possibly
expand slightly west overnight into Monday morning. A moderate
northwest flow along the Central Coast should keep things fairly
well mixed tonight and Monday with minimal marine layer stratus
expected with mild temperatures.

High pressure will slowly build into the area Tuesday into
Wednesday with a very slight warming trend. Expecting low clouds
and fog to spread back north towards the Central Coast as
northwest flow weakens and the marine inversion returns. Inland
areas will begin a warming trend by Wednesday as the ridge
strengthens.

.LONG TERM (THU-SUN)...04/137 PM.

The latest forecast ensembles suggest a warming and drying trend
continuing through the remainder of the week. Forecast ensemble 500
mb height means all climb through Friday then level off into the
weekend. A warm weather pattern is expected across the valleys,
mountain, and desert by late week with daytime highs reaching
near 90 degrees. The Antelope Valley will likely have its first 90
degree day of the calendar year, about a week later than normal.
Usually, KPMD and KWJF have their first 90 degree day around April
30th or May 1st, followed by their first 100 degree days around
June 13-14th. Closer to the coast, onshore flow and a persistent
marine layer should keep temperatures near seasonal levels. There
is a chance that low clouds and fog could hug the coast into late
week as subsidence aloft could clamp down on the marine layer
depth and tighten the marine inversion. This would likely keep
some marine layer induced low clouds into the beaches into the
afternoon and keep the temperatures near persistence.

&&

.AVIATION...05/0622Z.

At 06Z at KLAX, there was no marine layer nor inversion.

Low to moderate confidence in TAFs. Cigs may bounce frequently
between VFR and MVFR except desert airfields (KPMD, KWJF) thru
fcst pd. There is a 20-30% chance of showers across eastern LA
county tonight, and once again Monday afternoon.

KLAX...Low confidence in TAF. Conds may bounce between MVFR to
VFR cigs with several cloud decks at times expected thru fcst pd.
There is a 10% chance east wind component reaches 8 kts from 09Z
to 16Z Mon.

KBUR...Low confidence in TAF. Conds may bounce between MVFR to
VFR cigs with several cloud decks at times expected thru fcst pd.
There is a 15% chance of showers thru 12Z Mon.

&&

.MARINE...04/751 PM.

Winds are subsiding this evening, and as of 800 PM are below Gale
Force in all of the waters. Large steep seas remain throughout
much of the waters, but they have begun to subside as well. Across
the outer waters, seas are forecast to subside below 10 feet by
late Monday night or early Tuesday.

Conditions will continue improve late tonight into early Monday.
Then, sub-advisory conditions will be common through mid week.

&&

.BEACHES...04/1208 PM.

A large north to northwest swell associated with a low pressure
system will bring high surf to the Central Coast, Ventura, and Los
Angeles County Beaches through Monday morning. High Surf
Advisories have been issued for the aforementioned beaches, with
surf peaking this morning and afternoon then subsiding.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...High Surf Advisory in effect until 9 AM PDT Monday for zones
      340-346-354-366. (See LAXCFWLOX).
PZ...NONE.

&&

$$

PUBLIC...Gomberg/MW
AVIATION...Lund
MARINE...Ciliberti
BEACHES...Lund
SYNOPSIS...MW/Ciliberti

weather.gov/losangeles

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