865
FXUS66 KLOX 020300
AFDLOX

Area Forecast Discussion...UPDATED
National Weather Service Los Angeles/Oxnard CA
800 PM PDT Mon Jul 1 2024

.SYNOPSIS...01/759 PM.

A significant heatwave will impact the region this week through
early next week, with dangerously hot temperatures across much of
the area. High temperatures by mid to late week are expected to
reach 95 to 105 degrees in many areas away from the coast, with
highs upwards of 105 to 115 over interior valleys and foothills,
including the Antelope Valley. Very warm to hot conditions could
extend closer to the coast by late this week. Patchy night to
morning dense fog will be possible near the coast tonight into
early Tuesday.

&&

.SHORT TERM (MON-THU)...01/759 PM.

***UPDATE***

Highs today peaked in the 90s across many interior areas,
including some readings in the upper 90s in the Antelope Valley,
the San Fernando Valley, and in the Salinas Valley. Highs are
forecast to increase by anywhere from 3 to 12 degrees across the
area on Tuesday, aided by weak offshore gradients forecast for LAX
to Daggett and between Santa Maria to Bakersfield. Excessive Heat
Warnings will begin Tuesday morning across the mountains, Antelope
Valley and the far interior of San Luis and Santa Barbara
Counties, and by Wednesday morning for the remainder of the
valleys and Santa Monicas, excepting the coast and coastal basins.
The warnings have been extended through next Monday. The peak in
heating will occur Friday and Saturday, with Friday being the
warmest.

For the overnight period into early Tuesday, the marine layer is
expected to bring patchy dense fog to coastal areas, also
extending a short distance into some of the coastal valleys. As
the ridge aloft expanding over the area, the marine layer will
shrink, with any low clouds becoming confined closer to the coast.

Winds through the short term should be typical onshore winds each
afternoon to evening period, affecting the interior passes and
canyons, and the Antelope Valley.


.LONG TERM (FRI-MON)...01/215 PM.

The heat will really kick in later in the week into Saturday as
the high pressure center over northern California reaches 600dam.
Models still indicating some northerly flow developing across the
Central Coast and southern Santa Barbara County as well as the
northern mountains, creating a favorable pattern for hot
Sundowners Friday and Saturday evenings. While the hottest
temperatures will still be across inland area, strong downsloping
slow off the Santa Ynez Mountains will provide a temperature boost
across the coastal areas of southern Santa Barbara County with
highs well into the 90s possible and very warm overnight
temperatures as well.

Elsewhere, temperatures will continue to warm through Saturday.
Highs inland will be 10-15 degrees above normal and at the coast
5-10 degrees above normal with minimal and early clearing of
marine layer. Models are suggesting a few degrees of cooling
Sunday but then very little change Monday. While it`s possible
that temperatures may technically drop into more of heat advisory
category in some previously warned areas Sunday/Monday, opted to
just extend the Excessive Heat Warning through Monday.

The combination of these very hot temperatures, areas of low
humidities and possible sundowner winds will lead to fire weather
risks. Please see the fire weather discussion below for all the
details.

&&

.AVIATION...02/0255Z.

At 00Z at KLAX, the marine layer was 600 feet deep. The top of
the inversion was at 2600 feet with a temperature of 28 Celsius.

For 00Z TAF package, high confidence in KPRB, KPMD and KWJF TAFs
as CAVU conditions are expected thru the period. Moderate to high
confidence in KBUR and KVNY where cigs will most likely stay out
of the area, however some brief reduced vis around 12-14Z cannot
be ruled out. For 00Z Coastal TAFs, low to moderate confidence in
current forecast. Timing of return of CIG/VSBY restrictions could
be +/- 4 hours of current forecasts.

KLAX...Moderate confidence in 00Z TAF. Timing of return of
CIG/VSBY restrictions could be as early as 04Z and as late as 07Z.
Also, there is a 30% chance of LIFR conditions 12Z-15Z. No
significant easterly wind component is expected.

KBUR...High to moderate confidence in 00Z TAF. Cigs will most
likely stay out of the area, however some brief reduced vis and
clouds around 12-14Z cannot be ruled out.

&&

.MARINE...01/1141 AM.

For the Outer Waters, moderate to high confidence in current
forecast. Through tonight, high confidence in Small Craft Advisory
(SCA) level winds. For Tuesday through Thursday, high confidence
in winds and seas remaining below SCA levels. For Friday and
Saturday, there is a 20-30% chance of SCA level winds.

For the Inner Waters north of Point Sal, moderate to high confidence
in current forecast. There is a 40-60% chance of SCA level winds
through this evening. For Tuesday through Saturday, high
confidence in winds and seas remaining below SCA levels.

For the Inner Waters south of Point Conception, high confidence in
current forecast. Today through Saturday, winds and seas will
remain below SCA levels.

Patchy dense fog (with visibilities one nautical mile or less)
will continue to impact the coastal waters through the week. The
areal coverage of the dense fog will likely decrease each day.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...Excessive Heat Warning now in effect from 11 AM Tuesday to 6
      PM PDT Monday for zones 38-343>345-353-376>379-381>383. (See LAXNPWLOX).
     Excessive Heat Warning in effect from 11 AM Wednesday to 6 PM
      PDT Monday for zones 88-342-348-351-352-356>358-369>375-380. (See LAXNPWLOX).
PZ...Small Craft Advisory in effect until 9 PM PDT this evening
      for zone 645. (See LAXMWWLOX).
     Small Craft Advisory in effect until 3 AM PDT Tuesday for
      zones 670-673-676. (See LAXMWWLOX).

&&

$$

PUBLIC...MW/Smith
AVIATION...Phillips
MARINE...RAT
SYNOPSIS...Cohen/Smith

weather.gov/losangeles

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