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732
FXUS66 KLOX 241246
AFDLOX

Area Forecast Discussion...UPDATED
National Weather Service Los Angeles/Oxnard CA
546 AM PDT Mon Jun 24 2024

.SYNOPSIS...24/224 AM.

Dangerously hot weather will continue away from the coast
especially over the Antelope Valley. Elsewhere, there will be a
gradual cooling trend through the week. There is a slight chance
of thunderstorms today over the mountains and SLO county.

&&

.SHORT TERM (TDY-WED)...24/247 AM.

A lobe of PVA currently south of the Channel Islands is moving
from S to N. It has a few embedded showers in it and will bring a
slight chc (15 percent) of a shower or TSTM to the Channel
Islands, The Santa Barbara Channel and SBA county this morning.
Otherwise skies will be partly cloudy as debris clouds float
overhead. Only very minimal marine layer clouds today as the
clouds and humidity aloft have greatly disrupted the stratus
formation. The onshore flow this afternoon will be about 3 mb
strong than ydy and this will bring noticeable cooling to the
coasts and vlys. 591 dam hgts however will continue to bring the
heat to the interior. The vlys will not be warm enough for heat
advisories and these were cancelled. A heat warning was added for
the Western Antelope Foothills where triple digit heat will occur.
One more day of heat advisories for the interior of SLO and SBA
counties as there will be little or no change in temps from ydy`s
readings. Mid level moisture will combine with afternoon solar
induced instability over the mtns to bring a slight chc (20
percent) of TSTMs to the higher peaks of the LA/VTA mtns. This
morning`s vort lobe will be over SLO county this afternoon and
will also generate the same slight chc of TSTMs.

The strong onshore push will likely generate more coastal low
clouds tonight but given how disorganized the marine layer is now
it will likely take much longer for the clouds to develop. The
upper high will shift a little to the SW and this will bring dry
SW flow over the area and squash the risk of convection. Most
cst/vly locations away from the beaches will cool 2 to 5 degrees
and will end up 3 to 6 degrees above normal. The Antelope Vly will
continue to sizzle under 593 dam hgts and the heat warning will
persist there.

An upper will will move through the PAC NW on Wednesday. Weak
troffing will move over CA and hgts will drop to 588 dam. Onshore
flow will remain strong and there will be more and earlier
arriving marine layer stratus. The beaches will see slower
clearing. Most areas will cool 2 to 4 degrees which may be enough
over the Antelope Vly to end the Heat Warning early. The csts/vlys
will cool to near normal while the inland areas will end up 4 to 6
degrees above normal.

.LONG TERM (THU-SUN)...24/322 AM.

Both the EC and GFS as well as most of their respective ensembles
have trended away from their rather dire heat predictions they
both had earlier. Now the xtnd fcst looks pretty static. The upper
high will migrate to the east while a fairly stationary troffing
pattern sits over the west coast. This will keep dry SW flow over
the area and eliminate any convective threat. The marine layer
will be very shallow and may behave as it has lately with hardly
any inland penetration.

Max temps will slowly fall through Saturday as hgts fall. By
Saturday max temps will be 2 to 4 degrees blo normal. Onshore flow
will weaken some on Sunday and this will bring a few degrees of
warming to the area.

&&

.AVIATION...
-- Changed Discussion --
24/1245Z.

At 08Z at KLAX, the marine layer was 700 feet deep. The top of
the inversion was at 2400 ft with a temperature of 26 deg C.

High confidence in TAFs for KPRB, KBUR, KVNY, KPMD and KWJF.

High confidence in other TAFs through 08Z Tue, followed by
moderate confidence tonight uncertainty in cig development
tonight. There is a 30% chance of no cigs developing for sites
where they are forecasted tonight.

KLAX...High confidence through 08Z Tue, followed by moderate
confidence due to uncertainty in cigs tonight. There is a 30%
chance of BKn004-BKn008 cigs and 1/2SM-2SM vsby from 12Z-16Z Tue.
Good confidence that any east wind component will be under 5kt.

KBUR...High confidence in TAF.
-- End Changed Discussion --

&&

.MARINE...24/305 AM.

Moderate-to-high confidence in the winds and sea forecast. Low
confidence in the expected weather and possible gusty winds
associated with any thunderstorm activity.

For the Outer Waters and the inner waters along the Central Coast,
conditions expected to stay below Small Craft Advisory (SCA)
levels through Tuesday night, except for local gusty wind around
Point Conception and the Channel Islands during the
afternoon/evenings. Wednesday through Friday night, there is a
50-70 percent chance of SCA level winds, that will peak in the
afternoon and evenings. Choppy SCA level seas are also likely
for this time period.

Inside the southern California bight, winds
and seas will remain below Small Craft Advisory (SCA) levels
through at least early Wednesday. There is a around a 50% percent
chance of SCA level winds developing across the Santa Barbara
Channel, Wednesday afternoon and evening, and again Thursday
afternoon and evening.

In addition, a thunderstorm is currently occuring south of the
Channel Islands, and chances for thunderstorms will continue over
the waters through this evening,  as remnant moisture aloft from
post- tropical Cyclone Alberto move over the region. Otherwise, a
shallow marine layer depth will continue areas of dense fog
this morning.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...Heat Advisory remains in effect until 8 PM PDT this evening
      for zones 38-344-345-348-353-379. (See LAXNPWLOX).
     Excessive Heat Warning in effect until 8 PM PDT this evening
      for zone 381. (See LAXNPWLOX).
     Excessive Heat Warning remains in effect until 8 PM PDT
      Thursday for zones 382-383. (See LAXNPWLOX).
PZ...NONE.

&&

$$

PUBLIC...Rorke
AVIATION...Schoenfeld
MARINE...Hall/Schoenfeld
SYNOPSIS...30

weather.gov/losangeles

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