Monrovia, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

798
FXUS66 KLOX 170610
AFDLOX

Area Forecast Discussion...UPDATED
National Weather Service Los Angeles/Oxnard CA
1110 PM PDT Mon Jun 16 2025

.SYNOPSIS...16/113 PM.

High pressure over the region will maintain very warm temperatures
through much of the coming week, especially away from the coast
and across the interior portions of the area. Gusty northerly
winds will develop once again tonight across southern Santa
Barbara County and through the Interstate 5 Corridor. A gradual
cooling trend will develop late in the week.

&&

.SHORT TERM (MON-THU)...16/953 PM.

The latest water vapor imagery shows an upper-level ridge
remaining in place along the Baja California coast this evening,
while a weak disturbance that flattened the ridge some continues
to exit the region. A warm and dry weather pattern will continue
away from the coast as ridging aloft will continue to dominate
weather pattern through much of this week. Any low clouds and fog
will likely remain confined to the Central Coast and into South
Bay and Harbor portions of Los Angeles County through Tuesday
morning.

As the disturbance aloft vacates the region, a tight northerly
pressure gradient remains in place creating gusty northerly winds
across southern Santa Barbara County and through the Interstate 5
Corridor. A wind advisory was added for the Interstate 5 Corridor
this evening, in addition to the wind advisories remaining in
effect for the southwestern Santa Barbara and the Santa Ynez
mountain range. Wind gusts are already reaching advisory criteria
across southwestern Santa Barbara County this evening, but the
winds will increase overnight into the eastern portions of the
Santa Ynez range and through the Interstate 5 Corridor.

No additional updates are planned to the forecast.

***From Previous Discussion***

Overall, a warm stretch of weather will continue through at least
mid week as a ridge of high pressure sits over the West Coast.
Temperatures trended a little cooler today in most areas as
onshore flow to the east increased which created an earlier sea
breeze. The main exception to that is southern Santa Barbara
County where onshore flow to the north has decreased and has
actually turned offshore. Thus, temperatures there are trending
slightly warmer. And more importantly, the stage is being set for
a moderate Sundowner event tonight and again tomorrow night with
winds gusting to 50 mph through the canyons and passes from late
afternoon through early morning creating some fire weather
concerns. Similar concerns also for the I5 corridor, the Antelope
Valley, and interior SLO County.

Across the region, highs Tue/Wed are expected to be within 3 or
so degrees of today in most areas, except trending more on the
higher side of that across the interior portions of SLO County and
the Antelope Valley as well as southern SB County due to sundowner
winds. For the LA/Ventura County valleys looking for highs in the
90s to around 102. And Downtown LA around 90.

A trough will begin to replace the ridge Thursday that will start
a cooling trend that will carry into the weekend.

.LONG TERM (FRI-MON)...16/110 PM.

A trough of low pressure will continue across the West Coast
Friday and through the weekend and even into early next week
which means much cooler temperatures and increasing marine layer
stratus. High temperatures will drop to 3-6 degrees below normal
area-wide through early next week with a steady dose of night and
morning marine layer that may not fully clear some coastal areas.
Gusty onshore winds will continue across the Antelope Valley each
afternoon and evening.

&&

.AVIATION...17/0609Z.

At 0505Z at KLAX, the marine layer was 800 feet deep. The top of
the inversion was around 5000 feet with a temperature of 26 C.

High confidence in all TAFs xcp for KSBP (20 percent chc of LIFR
cigs 11Z-16Z), KLAX and KSMO (40 percent chc of LIFR cigs 12Z-16Z)
and KLGB (30 percent chc of no cigs).

KLAX...Low confidence in TAF from 12Z to 16Z with a 40 percent chc
of OVC004 conds, otherwise high confidence. Any east wind
component will be less than 6 knots.

KBUR...High confidence in CAVU TAF.

&&

.MARINE...16/142 PM.

High confidence in gusty Small Craft Advisory (SCA) level
northwest winds across the Outer Waters and Inner Waters along the
Central coast through the week. A Gale Warning is in effect for
the Outer Waters through Tuesday night, and for the northern
Inner Waters through this evening. For Tuesday afternoon through
evening, there is a 40% chance of Gale force winds again in the
northern Inner Waters. Seas will hover around 10 feet through the
week, increasing to 10 feet this weekend. Gale force winds will
be possible again by the end of the week.

Gusty SCA winds for western and southern portions of the Santa
Barbara Channel in the afternoon and evening hours are likely
through Tuesday, with lower confidence thereafter. A Gale Watch is
in place for Tuesday afternoon through evening, with Gale force
winds focused across the western portions and away from Santa
Barbara, Ventura, and Channel Islands Harbors. Confidence in the
Gale force winds being widespread enough to warrant a Gale Warning
has trended lower since this morning.

Moderate confidence in conditions remaining below advisory levels
in the Inner Waters off the Los Angeles and Orange County coasts
through the week. However, localized W to NW SCA level wind gusts
may occur in the afternoon and evening hours near Malibu and
through portions of the San Pedro Channel through Tuesday.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...Wind Advisory remains in effect until 9 AM PDT Tuesday for
      zones 349-351-352. (See LAXNPWLOX).
     Wind Advisory in effect until 9 AM PDT Tuesday for zone 378. (See LAXNPWLOX).
PZ...Small Craft Advisory in effect until 3 AM PDT Wednesday for
      zone 645. (See LAXMWWLOX).
     Small Craft Advisory in effect until noon PDT Tuesday for
      zone 650. (See LAXMWWLOX).
     Gale Watch in effect from Tuesday afternoon through late
      Tuesday night for zone 650. (See LAXMWWLOX).
     Gale Warning in effect until 3 AM PDT Wednesday for zones
      670-673-676. (See LAXMWWLOX).

&&

$$

PUBLIC...Hall/MW
AVIATION...Rorke
MARINE...Lewis
SYNOPSIS...Ciliberti

weather.gov/losangeles

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