356
FXUS66 KLOX 280644
AFDLOX
Area Forecast Discussion...UPDATED
National Weather Service Los Angeles/Oxnard CA
1144 PM PDT Mon Oct 27 2025
.SYNOPSIS...27/909 AM.
The first Santa Ana Wind event of the season is expected Tuesday
and Wednesday, bringing very warm temperatures to the coasts and
valleys and gusty winds to the typically wind prone corridor of
Los Angeles and Ventura Counties as well as most mountains. Late
this week through the weekend, temperatures will remain above
normal with no rain chances in the foreseeable future.
&&
.SHORT TERM (MON-THU)...27/816 PM.
***UPDATE***
Big switch in the weather underway. Currently there is a 6mb
offshore push from the north and about a 1 mb offshore push from
the east. The trends are impressive as well, with both in the 4 to
5 mb range. This offshore push from the north is generating wind
gusts 35 to 45 mph through the passes and canyons of the Santa
Ynez range. Later tonight advisory level winds will develop
through the i-5 corridor and spill into the Santa Clarita Vly. By
dawn the offshore push from the east will have increased to about
5 mb and this will switch the winds to the NE and the first Santa
Ana wind event of the season will begin. Look for 40 to 50 mph
gusts through the Santa Ana corridor (Santa Clarita Vly to Pt
Mugu).
The Santa Ana winds will also produce a marked warm up. Look for
10 to 15 degrees of warming across all of the csts and vlys. This
will raise max temps for the csts/vlys into the mid 80s to mid 90s
or about 12 degrees above normal. A heat advisory is in effect for
the csts/vlys.
As with all Santa Anas the humidities will be in the single digits
and teens. The combination of low humidities, high temperatures
and gusty winds will produce red flag conditions through the Santa
Ana Wind Corridor.
The current forecast is well on track and no updates are planned.
***From Previous Discussion***
The first Santa Ana Wind event of the season will start Tuesday
(tomorrow) and last through Wednesday, driven by offshore surface
pressure gradients that will set up across the region. A
relatively colder airmass has surged into the Central Valley,
resulting in a surface high to contrast the surface low pressure
along the SoCal Coast (the LAX-DAG and LAX- BFL gradients are
likely to peak around 5 mb offshore). This imbalance will drive
the offshore winds out the northeast over the next couple days.
Expect northeast winds to pick up tonight along the San Luis
Obispo County Santa Lucia Mountains and coastal areas (including
Morro Bay and Cayucos), then developing early Tuesday morning
across the Santa Ana wind prone corridor of Los Angeles and
Ventura Counties. Winds Advisories are in effect the windiest
areas tonight through Tuesday, with additional advisories
possible for late Tuesday night into Wednesday morning (see NPWLOX
for more details).
The warm downsloping winds will lead to temperatures well above
normal temperatures across the region, including the coastal
plains and beaches. Heat Advisories are currently in effect
across much of Ventura and Los Angeles Counties Tuesday through
Wednesday, where daytime highs will be in the upper 80s to low
90s, which is 10 to 15 degrees above normal (see NPWLOX for more
details). Temperatures will approach daily records, especially
near the beaches.
Additionally, the influx of dry air from the interior will yield
very low relative humidities. Gusty winds and these dry
conditions will result in elevated to Critical Fire Weather
conditions, and Red Flag Warnings have been issued for the
Western San Gabriel Mountains, Santa Susana Mountains, and the
Southeastern Ventura County Valleys (see RFWLOX for more details).
Residents in or near theses areas are advised to check for
multiple ways to recieve weather and emergency alerts and make
preparations to evacuate in an emergency wildfire situation.
The Santa Ana winds will keep marine layer clouds at bay for the
next few days, with some low clouds and fog likely to return
Thursday morning. Heat will also let up somewhat on Thursday,
through temperatures will remain above normal with highs in the
80s common.
.LONG TERM (FRI-MON)...27/148 PM.
An extended period of broad ridging is favored to prevail over
the region Friday into early next week, with little variation
between forecast models. This will keep temperatures generally
above normal, though offshore surface pressure gradients are
expected to decrease, which will will allow for a cooling trend
for Friday. The ridge is likely to strengthening over the weekend,
resulting a minor bump in temperatures. At this point, heat
products are not likely to be needed. Additionally, there is
little indication of a pattern change in the foreseeable future,
with the next chance for rain well beyond the forecast period
(late next week in early November).
&&
.AVIATION...28/0641Z.
At 0537Z at KLAX, the marine layer was 600 ft deep. The top of
the inversion was 3700 ft with a temperature of 21 C.
High confidence in KWJF and KPMD TAFs.
Moderate confidence in remainder of TAFs. Low confidence in low
cloud evolution tonight into early Tuesday morning. NE winds
and/or weak to mdt LLWS will be a concern after 12Z Tuesday at
KCMA KOXR KVNY and KSBP, as well as weak to mdt LLWS and UDDF
near higher terrain. Winds may not shift west at KCMA through the
period.
KLAX...Moderate to high confidence in VFR conditions through 08Z.
Thereafter, low confidence with a 40% chance for IFR CIGs 005-008
to develop from 09Z to 16Z Tue, with moderate confidence in MVFR
VSBYs 4 to 5SM. No significant east wind component expected.
KBUR...Moderate confidence in TAF. VFR conditions expected
through fcst pd. NE winds will form over the region on Tuesday,
with mdt confidence that they will not surface at airport, but
some weak to moderate LLWS may form.
&&
.MARINE...27/606 PM.
The current NW winds will shift to N-NE through Tuesday. High
confidence in Small Craft Advisory (SCA) winds and seas through
tonight from the Central Coast (including nearshore) to San
Nicolas Island. Localized GALE force wind gusts possible across
an area from Point Conception down to buoy 46069 and about 30 NM
to the west through this evening.
NE winds will impact the nearshore waters Tuesday and Wednesday
morning from Ventura to Santa Monica, & along the Central Coast.
High confidence winds will peak at least in the 15-20 knot range.
There is a 30% chance that winds cross over into SCA criteria in
terms of speed and duration.
NW winds will likely return to SCA levels from the Central Coast
to San Nicolas Island by Thursday.
Patches of dense fog will likely form Thursday into Friday.
&&
.FIRE WEATHER...27/357 PM.
Gusty north winds combined with a drying trend will bring elevated fire weather
conditions through this evening across portions of the mountains, southern
Santa Barbara county, and Antelope Valley. Late tonight into Wednesday a weak
to moderate Santa Ana wind event will develop across southern California.
Northeast winds gusting 30 to 40 mph will be common on Tuesday across the
typical Santa Ana wind prone corridors of LA/Ventura counties, with isolated
gusts up to 45 mph across favored mountain/foothills areas. The offshore
winds are expected to diminish some in most areas Tuesday night into Wednesday
(with gusts mostly in the 20 to 35 mph range). However, high resolution models
indicating a secondary burst of wind gusts 35 to 45 mph late Tuesday night into
Wednesday morning across the western San Gabriels, Santa Susanas, and the
Highway 118 corridor of the eastern Ventura county Valleys (near Moorpark, Simi
Valley). This Santa Ana wind event will be associated with very warm and
dry conditions, especially across coastal/valley areas where downslope warming
will occur. Minimum humidities of 8 to 15 percent will be common across much
of LA/Ventura counties, falling to 5 to 10 percent on Wednesday. In addition,
there will be very poor humidity recoveries on Tuesday night with many wind
prone areas/foothills remaining in the 10 to 20 percent range.
The combination of gusty Santa Ana winds, very warm temperatures, and very
low humidities will bring widespread elevated to brief critical fire weather
conditions across the region Tuesday into Wednesday, especially wind corridors
of LA/Ventura counties where 2 to 5 hours of Red Flag conditions could occur
each day. The most enhanced wind areas on Tuesday and Wednesday (western San
Gabriel mountains, Santa Susanas, and southeast Ventura valleys mainly near
Simi Valley/Moorpark) will likely see 6+ hours of Red Flag durations,
resulting in the issuance of the Red Flag Warning for the longer duration
threat. Despite recent rains, local fire agencies indicating fuels are still supportive
of rapid fire spread and extreme fire behavior across portions of the forecast
area. Live Fuel Moisture values are still in the 65 to 75 percent range across
much of the area, with only a shallow grass crop forming in many areas
after recent rains. Residents in or near the Red Flag Warnings ares are
advised to check for multiple ways to recieve weather and emergency alerts
and make preparations to evacuate in an emergency wildfire situation.
Winds will continue to weaken on Thursday, but a light offshore wind influence
will continue to maintain very warm and dry conditions through the weekend
away from the coast.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
CA...Wind Advisory in effect from 6 AM to 4 PM PDT Tuesday for
zones 88-355-358-374-375-378-379. (See LAXNPWLOX).
Wind Advisory now in effect until 11 AM PDT Tuesday for zones
340>342-345. (See LAXNPWLOX).
High Surf Advisory in effect until 9 AM PDT Tuesday for zones
340-346. (See LAXCFWLOX).
Heat Advisory remains in effect from 10 AM Tuesday to 7 PM
PDT Wednesday for zones 354-355-358-362-366>375-548. (See LAXNPWLOX).
PZ...Small Craft Advisory in effect until noon PDT Tuesday for
zone 645. (See LAXMWWLOX).
Small Craft Advisory in effect until 3 AM PDT Tuesday for
zones 670-673-676. (See LAXMWWLOX).
&&
$$
PUBLIC...Schoenfeld/Rorke
AVIATION...Black/Lund
MARINE...RK/Black
FIRE...Gomberg
SYNOPSIS...RS
weather.gov/losangeles
Experimental Graphical Hazardous Weather Outlook at:
https://www.weather.gov/erh/ghwo?wfo=lox NWS LOX Office Area Forecast Discussion