963
FXUS66 KLOX 061938
AFDLOX

Area Forecast Discussion
National Weather Service Los Angeles/Oxnard CA
1238 PM PDT Sat Jul 6 2024

.SYNOPSIS...06/511 AM.

A long-lasting and extreme heatwave will continue across the
region, and especially the interior, through much of next week.
There is a high risk for dangerous heat illness and fast-growing
fires. High temperatures will reach 95 to 105 degrees in many
areas away from the coast, and 105 to 115 across interior valleys
and mountains. All-time high temperature records will be
threatened in the Antelope Valley today. Dense fog may develop
across some beaches during the night and morning hours.

&&

.SHORT TERM (TDY-MON)...06/906 AM.

***UPDATE***

Strong upper level ridging with H5 heights around 595-596 dam
will continue the heat wave over SW CA today. Impressive warm
layer in the 12Z VBG sounding and latest LAX ACARS soundings, with
a very strong inversion to about 1500 to 4500 ft or so where
temps were in the lower 90s peaking around 95 to 96 deg around
2500-3500 ft. The potential max temp in the VBG sounding was 114
deg...up from 108 deg 24-hours prior. Some low temps in the
foothills and lower mtns did not drop below 90 degrees this
morning.

There will likely be a quick warm-up for the coast and adjacent
vlys this morning with max temps possible by noon or early
afternoon in some areas as onshore pressure gradients to the E
and N will increase quickly into the afternoon. NAM fcst 00Z (5
PM) gradients for LAX- DAG is +8.0 mb (up 5.8 mb in 24-hours) and
for LAX-BFL +6.1 mb (up 6.2 mb in 24-hours).

Hi temps for the inland coast and adjacent vlys are expected to
reach the 90s to about 105 but should cool some this afternoon
especially the closer you get to the coast. For the inland vlys
and lower mtns, temps will soar into the 105 to 115 degree range,
altho local temps up to 118 deg cannot be ruled out in the SLO
County interior vlys. The Antelope Vly will likely reach 112 to
117 deg this afternoon, with a chance of tying or exceeding the
all-time highs at Palmdale (113 deg) and Lancaster (115 deg).
Sandberg could approach their all-time hi of 107 deg, and Paso
Robles could come close to tying their all-time high of 117 deg.

Needless to say, Excessive Heat Warnings and Heat Advisories
continue today for just about the entire forecast area, with only
the Central Coast beaches and the beaches of VTU/L.A. Counties not
in any of these products. Please see the latest Non-Precipitation
Weather Message (LAXNPWLOX) for further details on these warnings
and advisories.

***From Previous Discussion***

The long duration period of dangerously hot weather continues for
the region for the entire next week due to unusually high pressure
aloft over the region. This is a dangerous situation with all the
ingredients for a high risk of heat-illness and fast growing
fires. PLEASE avoid hiking in the mountains and the hills through
this weekend, make plans on how you will stay cool, and stay away
from anything that could spark a fire.

While the coastal locations will be a few degrees cooler than
yesterday thanks to increasing onshore trends, the far interior
locations such as the Antelope Valley, will warm a few degrees
thanks to a slight increase in upper level heights from 596 to 597
dam. As a result, Lancaster, Palmdale, Sandberg, and Paso Robles
have the potential of breaking daily high record temperatures
today.

On Sunday, 5-10 degrees of cooling is expected across the region
in part due to a slight lowering in upper level heights for the
interior areas, and the increase in onshore trends across the
coastal areas. Then little to no change is expected in
temperatures from Sunday to Monday. Temperatures are still
expected to be 3-10 degrees above normal across the coasts and
12-20 degrees across the interior mountains and far interior
valleys through the weekend.

As for low clouds, they were slower to appear this morning. Clouds
have just started to overspread the Los Angeles Coast from the
south and inch into the Central Coast from the north. These
clouds are expected to burn off by the morning, but remain just
off the coast. Sunday is a different story, as the onshore push
may allow the clouds to push deeper inland, and then remain across
the beaches through the day. However, sundowners across the Santa
Barbara Coast are expected Sunday night which will keep low
clouds off the Santa Barbara that night.

.LONG TERM (TUE-FRI)...06/515 AM.

As you will hear day after day, the hot and dry weather keeps
going through the next week. The upper level high, centered over
southeast California on Monday, will slowly move north into
Nevada Tuesday through at least Thursday. Combined with a weak
upper level trough nudging into the region from the west, onshore
gradients will weaken and northerly gradients will turn offshore
through midweek, resulting in temperatures warming up to 8 degrees
on Tuesday. Then, Tuesday through Thursday looks to be a broken
record with little to no change each day and temperatures 5-10
degrees above normal. The aforementioned sundowners across Santa
Barbara South Coast will continue each night Sunday through
Wednesday, keeping clouds off the south coast and allow for
further heating there - up to 10 degrees above normal for this
time of year.

&&

.AVIATION...06/1937Z.

At 18Z at KLAX, the marine layer was 1500 feet deep. The top of
the inversion was at 4200 feet with a temperature of 35 deg C.

Strong eddy circulation has caused the marine layer to deepen,
and clouds to expand into all coastal areas south of Point
Conception. Cigs were most entrenched across L.A, County, where
clouds were just dissipating in the San Gabriel Valley. Cigs were
mostly in the IFR to LIFR categories, with local VLIFR conds.
Expect cigs to slowly clear this afternoon, except linger near the
beaches from southern SBA County to L.A. County thru the
afternoon.

Expect widespread low clouds in all coastal areas tonight, with
clouds pushing into the San Gabriel and Santa Ynez Valleys by late
evening, and likely pushing into the San Fernando Valley and
lower valleys of Ventura County late tonight. Conds will be mostly
IFR to LIFR, with local VLIFR conds north of coastal sections of
L.A. County and in the valleys.

KLAX...Low confidence in the 18Z TAF. There is a 30% chance that
cigs will linger thru 23Z. There is a 30% chance that cigs will
arrive as early as 01Z or as late as 06Z this evening. There is a
30% chance that cigs will rise into the MVFR category as early as
11Z tonight. There is a 20-30% chance that the east wind of 7 to
9 kt will persist thru 22-23Z. There is a 20% chance of at east
wind component of 7-8 kt from 10Z-16Z.

KBUR...Moderate confidence in the 12Z TAF. There is a 30% chance
that IFR or LIFR cigs will arrive as early as 09Z tonight.

&&

.MARINE...06/905 AM.

In the Outer Waters, Small Craft Advisory (SCA) level winds have
dropped below SCA levels, except in the northern zone (PZZ670)
where this will not occur until tonight. There is a 20-30% chance
of SCA level winds the central zone (PZZ673) late this afternoon
and evening.

For the most part, expect winds to remain below SCA levels Sun
thru Wed night. However, there is a 30% chance of SCA level NW
winds in the far outer waters and from near Pt. Conception to NW
of San Nicolas Island during the late afternoon thru late evening
hours.

In the inner waters N of Pt. Sal, there is a 30% chance of SCA
level winds during the afternoon/evening hours today thru Tue,
otherwise SCA conds are not expected thru Wed night.

In the inner waters south of Pt Conception, SCA conditions are
not expected thru Wed night. However, there is a 30% chance of
SCA winds during the afternoon/evening hours Tue and Wed in
western portions of the Santa Barbara Channel, mainly from Santa
Cruz Island to the SBA County south coast from Pt. Conception to
Gaviota to Refugio State Beach.

Areas of dense fog will continue to affect the coastal waters
through this afternoon. Please reference the Marine Weather
Statement for additional information.

&&

.BEACHES...06/555 AM.

A moderate southerly swell will affect the Southern California
coastal waters through Sunday, with a 15-17-second period this
weekend. While surf is not expected to be particularly high, surf
heights of up to 4 to 6 feet are anticipated at beaches exposed to
southerly swell, especially the LA and Ventura County beaches.

The significant wave energy with the long-period swell will
combine with the elevated surf to create dangerous conditions at
area beaches, with powerful and dangerous rip currents expected.
This is especially the case for the south-facing beaches of LA
and Ventura Counties. A Beach Hazards Statement is in effect
through the weekend to address these concerns.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...Excessive Heat Warning remains in effect until 9 PM PDT
      Wednesday for zones 38-343>345-353-376>379-381>383. (See LAXNPWLOX).
     Excessive Heat Warning remains in effect until 9 PM PDT
      Sunday for zones 88-342-348-351-352-356>358-369>375-380. (See LAXNPWLOX).
     Heat Advisory remains in effect until 9 PM PDT this evening
      for zones 341-347. (See LAXNPWLOX).
     Beach Hazards Statement in effect through Sunday evening for
      zones 354-362-366. (See LAXCFWLOX).
     Heat Advisory remains in effect until 9 PM PDT Sunday for
      zone 548. (See LAXNPWLOX).
     Red Flag Warning in effect until 6 AM PDT Monday for zones
      378-381. (See LAXRFWLOX).
PZ...Small Craft Advisory in effect until 3 AM PDT Sunday for zone
      670. (See LAXMWWLOX).

&&

$$

PUBLIC...Lund/DB/Sirard
AVIATION...DB
MARINE...DB
BEACHES...DB
SYNOPSIS...MW

weather.gov/losangeles

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