344
FXUS66 KLOX 132144
AFDLOX

Area Forecast Discussion...UPDATED
National Weather Service Los Angeles/Oxnard CA
244 PM PDT Sat Jul 13 2024

.SYNOPSIS...13/128 PM.

Scattered showers and thunderstorms are expected to diminish early
this evening, with only a slight chance Sunday afternoon across
northeast Los Angeles County. A cooling trend will continue across
the area through at least Tuesday before a warming trend develops
for the end of next week. Extreme heat is possible across the
interior by next weekend.

&&

.SHORT TERM (TDY-TUE)...13/159 PM.

A very active day today with numerous thunderstorms, but so far
with very little rain. This is particularly concerning for the
interior areas where the fuels are rapidly drying and lightning
strikes could easily spark a fire. Thunderstorms have been mostly
focused over the western portion of the forecast area so far today,
including Santa Barbara and western Ventura County. And as hi res
models predicted yesterday we`re starting to get increasing
development across the Antelope Valley. Expecting convective
activity to continue area-wide through early evening before
settling down overnight as the air mass stabilizes. Based on
current satellite and radar trends southern LA County and eastern
Ventura County are much less likely to get convective activity
today, but leaving at least a slight chance in there to be on the
safe side. So far most of the storms have dropped very little
rain, but as updraft speeds increase through the afternoon and tap
into more moisture aloft there could be some brief heavy showers
as well as hail and gusty winds. Can`t rule out isolated flooding,
especially in the Antelope Valley.

Sunday is expected to me a much less active day overall as the
flow aloft veers to the south and precipitable waters decrease.
However, hi res models still picking up on enough instability and
moisture to warrant a slight chance of showers/storms across the
eastern Antelope Valley and adjacent foothills and mountains.
Otherwise, a fairly quiet day expected weather-wise with continued
cooler temperatures inland.

No significant weather issues expected early next week as the high
pressure that`s been over the west weakens and shifts far enough
east to help bring temperatures down closer to normal levels. In
fact, by Monday most areas except the Antelope Valley will be 2-4
degrees below normal.

.LONG TERM (WED-SAT)...13/211 PM.

Ensemble solutions continue to favor a warming trend starting
Wednesday and going through next weekend, especially for interior
areas again. By next Saturday chances are increasing that another
round of excessive heat warnings will be needed across the
Antelope Valley with highs again approaching 110. Warming is
expected across the mountains and valleys as well but less
confident on how hot it will get there. Current forecast gradients
do show some decrease later next week and the GFS indicate
significant warming at 950mb as well. Chances for Paso Robles
reaching 110 are still under 20% and chances for Woodland Hills
reaching 105 around in the 20-30% range. In any case, another
fairly long warming spell is expected the latter half of next week
with the focus again across the interior.

&&

.AVIATION...13/1806Z.

At 18Z at KLAX, the marine layer was 1800 feet deep. The top of
the inversion was at 5800 feet with a temperature of 25 deg C.

There is a low, but non-zero chance of isolated thunderstorms at
all sites 18Z Sat-06Z Sun.

Moderate confidence in TAFs for KPRB, KPMD, and KWJF. For these
sites, there is a 20% chance for thunderstorms 18Z Sat-06Z Sun.

Moderate confidence in coastal TAFs. Cig hgts may be off by +/-
300 ft. Flight cat transitions may be off by +/- 2 hours.

KLAX...Moderate confidence in TAF. Flight cat transitions may be
off by +/- 2 hours. No significant easterly wind component is
expected.

&&

.MARINE...13/243 PM.

Small Craft Advisory (SCA) conditions are not expected through
the weekend. There is a 30% chance of SCA winds across the Outer
Waters starting Monday afternoon, with chances increasing to 40%
Wednesday into Thursday. In addition, there is a 20-30% chance of
SCA winds across the far western portion of the Santa Barbara
Channel during each afternoon through overnight hours beginning
Monday through the week. A long period south swell is expected to
arrive Tuesday and may lead to elevated surf conditions and high
rip current potential through Thursday.

Isolated thunderstorms will be possible (about a 20% chance)
through early this evening. Any thunderstorm that forms will be
capable of producing locally gale force winds, rough seas, and
dangerous lightning.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...Excessive Heat Warning remains in effect until 9 PM PDT this
      evening for zones 38-343>345-353-376>379-381>383. (See LAXNPWLOX).
     Red Flag Warning in effect until 9 PM PDT this evening for
      zones 342>345-348-351>353-356-357-376>383. (See LAXRFWLOX).
PZ...NONE.

&&

$$

PUBLIC...MW/MW/MW/Rorke
AVIATION...jld
MARINE...Smith
SYNOPSIS...MW

weather.gov/losangeles

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