Sylmar, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

100
FXUS66 KLOX 221809
AFDLOX

Area Forecast Discussion...UPDATED
National Weather Service Los Angeles/Oxnard CA
1109 AM PDT Sun Jun 22 2025

.SYNOPSIS...22/251 AM.

Gusty northerly winds will continue across southern Santa Barbara
County through early Monday. Otherwise, warmer temperatures are
expected today then turning cooler Monday and Tuesday with
increasing night and morning low clouds and fog.

&&

.SHORT TERM (TDY-TUE)...22/905 AM.

***UPDATE***

The marine inversion this morning ranged from about 400 ft deep at
VBG to near 2500 ft deep at LAX. Very strong offshore pressure
gradient trends to the E (LAX-DAG -6.1 mb in 24-hours as of 15Z)
has helped to keep low clouds away from most areas, with varying
amounts of low clouds confined mainly to the L.A. County coast
into the San Gabriel Vly. These low clouds should dissipate before
noon. Otherwise, sunny skies can be expected across the forecast
area thru this afternoon.

There was some leftover sub-Advisory level NW-N wind gusts over
portions of the L.A. County mtns and SW SBA County this morning.
Breezy to gusty SW-NW winds can expected this afternoon for many
areas as pressure gradients start to trend onshore.

Temps across the region today are forecast to be several degrees
warmer than Sat, but highs should still be about 2-10 deg below
seasonal norms. Afternoon temps should top out from the upper 60s
and 70s along the coast to the upper 70s and 80s over the vlys,
lower mtns and deserts.

***From Previous Discussion***

While winds are expected to drop off quickly across the I5 region
today and remain relatively light the rest of the week, we`re
still looking at one more night of gusty winds in southern Santa
Barbara County tonight with gusts to 35-45 mph.

Aside from the winds, the forecast is fairly dull. Several degrees
of warming are expected today across inland areas as onshore flow
is weakening rapidly. The warmup will be short lived as another
low pressure system will drop south through California and sit
over the Central Valley Monday and Tuesday. This will increase
onshore flow again leading to cooler temperatures and a return to
night and morning low clouds and fog, especially along the Central
Coast.

.LONG TERM (WED-SAT)...22/316 AM.

Weak high pressure is expected to return Wednesday and remain
through the end of the week. As a result, temperatures will
increase back to near (or even slightly above) normals for this
time of year. Not expecting any strong winds during the period
except for the typical Antelope Valley breezes each afternoon.
Overall, very seasonable weather next week that will likely carry
into the following week.

&&

.AVIATION...22/1808Z.

At 1644Z at KLAX, the marine layer was 2000 ft deep. The top of
the inversion was at 4500 ft with a temperature of 17 C.

Overall, moderate to high confidence in 18Z TAF Package.

High confidence in VFR TAFs for desert airfields (KPMD, KWJF).
Moderate confidence in remaining TAFs. For sites with forecasted
CIGs, arrival and departure times may be off by an hour or two,
with minimum flight cats off by one. Also, there is a 20% chance
IFR CIGs arrive at KSBA from 14Z to 18Z Sun.

KLAX...Moderate confidence in 18Z TAF. Arrival and departure of
MVFR CIGs 012-025 should be within +/- 1 hour of forecast. There
is low chance (15%) CIGs initially arrive high-end IFR. There is a
40% chance of east wind component reaching 8 kts from 10Z to 16Z
Mon.

KBUR...Moderate confidence in 18Z TAF. There is a 40% chance
IFR/MVFR cigs arrive from 10Z to 16Z Monday (+/- 1 hour).

&&

.MARINE...22/809 AM.

Winds are weakening quicker than expected, so lowered all the
hazards one category. The waters beyond 20 miles from shore will
remain in Small Craft Advisory (SCA) through at least early Monday
morning. Local Gale force gusts to 35 kt this evening cannot be
ruled out across the Outer Waters. Moderate chances of low-end
SCA winds Tuesday afternoon and evening. Winds will likely
increase by 5-10 knots Wednesday and Thursday.

While low confidence based on the recent poor performance of our
best computer projections, SCA are possible this afternoon and
evening for the nearshore waters of the Central Coast and the
Santa Barbara Channel (western half has highest chances).
Otherwise, fairly seasonal conditions are likely for the rest of
the week.

The currently widespread steep seas will slowly subside through
Tuesday.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...Small Craft Advisory in effect until 11 PM PDT this evening
      for zones 645-650. (See LAXMWWLOX).
     Small Craft Advisory in effect until 9 AM PDT Monday for
      zones 670-673-676. (See LAXMWWLOX).

&&

$$

PUBLIC...MW/Sirard
AVIATION...Black
MARINE...Kittell/Black
SYNOPSIS...MW

weather.gov/losangeles

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