Diamond Bar, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

530
FXUS66 KLOX 021008
AFDLOX

Area Forecast Discussion
National Weather Service Los Angeles/Oxnard CA
308 AM PDT Wed Jul 2 2025

.SYNOPSIS...30/1100 PM.

Skies will be clear except for night through morning low clouds
across the coasts and some valleys through next weekend.
Afternoon high temperatures will be 3 to 6 degrees below normal
through the weekend.

&&

.SHORT TERM (TDY-FRI)...02/1206 AM.

The streak of benign weather will continue through the short term
and through the weekend as well. A little dry trof will move
through today and will produce, at worst, some mtn CU. Thursday
will feature a little pop up ridge followed by another trof on
Friday. Hgts mostly rise through the period from 580 dam this
afternoon to about 588 dam on Friday. At the sfc mdt to stg
onshore flow will persist through the 3 day period.

The night through morning low cloud pattern will continue but the
coverage will lessen each morning as the the hgts rise and smoosh
the marine layer down.

Max temps today will mostly be in the 70s for the csts and 80s for
the vlys. Local vly hot spots will see highs in the lower 90s. A
little strong onshore push from the south will bring some cooling
to the vlys but otherwise max temps will be similar to today. The
interior will see noticeable cooling on Friday, but there will be
little change across the cst/vlys.

Look for a weak Sundown this evening and a stronger one that could
reach advisory levels on Friday night.

.LONG TERM (SAT-TUE)...02/259 AM.

Hgts will hover between 588 dam and 590 dam Sat thru Tue. The sfc
gradients will weaken esp Tuesday when neutral or even weak
offshore flow could develop. Night through morning low clouds will
continue but the high hgts and weaker onshore flow will keep most
of the vlys cloud free. Most areas will see some warming each day
Sat through Mon with Monday`s temps south of Pt Conception reaching
the mid 70s to mid 80s for most of the csts and mid 80s to mid
90s for the vlys. The Central Coast will see max temps from the
mid 60s to 70s csts and lower to mid 80s in the vlys. Despite this
warm up most max temps will remain a few degrees blo normal
(except 6 degrees blo normal for the Central Coast). The decrease
in onshore flow is forecast to bring 2 to 4 degrees of warming to
all of the area on Tuesday with a 30 percent chc of 4 to 8
degrees.
Above normal confidence continues for a significant warm up
starting Tue or more likely Wed with moderate to possible high
heat impacts over the coastal valleys and interior. Triple digit
heat is possible for warmer coastal valleys to the interior. This
warm up would likely last to at least Friday. Monsoon moisture
may push as far west as Ventura County by the middle of next week
which would increase the heat concerns closer to the coast as
well. There is a small (10 percent chance) of thunderstorms over
the mtns and deserts of LA/VTA Counties beginning Tuesday. Any
TSTM that forms could produce dry lightning, gusty winds, and
local flooding.

&&

.AVIATION...02/0531Z.

At 0519Z at KLAX, the marine layer was 1200 ft deep. The top of
the inversion was at 2800 feet with a temperature of 23 C.

High confidence in TAFs for KPRB, KWJF, and KPMD. There is a 15%
chance for LIFR to IFR conds at KPRB between 08Z and 16Z.

Low confidence in TAFs for KBUR and KVNY with 40% percent chc of
LIFR to IFR cigs through 16Z.

Moderate confidence in remaining TAFs. Lowest cig height may be
off by +/- 300 feet. Lower confidence in time of dissipation of
cigs Wed (+/- 2 hours). There is a 30% chance for no clearing at
KCMA, KLAX, KSMO. There is a 40% chance for SCT conds at KOXR
after 20Z.

KLAX...Moderate confidence in TAF. There is a 10% chance for
OVC003-004 cigs through 15Z. There is a 30% chance for not
clearing of low clouds Wed. No significant east wind component is
expected through Wed, then moderate confidence in any east wind
component remaining below 6 kts between 07Z Thursday and the end
of the period.

KBUR...Low confidence in TAF with 40% chc of BKN002-008 cigs
through 17Z.

&&

.MARINE...02/128 AM.

Small Craft Advisory (SCA) winds are likely across the Outer
Waters much of the time through the 4th of July Weekend, with a
lull possible tonight into Thursday morning before ramping back
up. SCA winds are also likely each afternoon and evening for the
nearshore waters along the Central Coast from Thursday through the
weekend. Local Gale Force wind gusts are possible Thursday
through Sunday, with best chances around the western Channel
Islands and in the northern Outer Waters Thursday afternoon and
evening (30% chance). Seas will build to 8 to 10 feet at times
from this afternoon through the weekend.

Inside the southern California bight, there is a moderate
(30-50%) chance of SCA level winds each day through the weekend
during the afternoon and evening hours through the Santa Barbara
Channel (strongest winds focused in the western portions), near
Point Dume, and into the San Pedro Channel.

Patchy dense fog may affect the coastal waters, especially north
of Point Conception overnight and in the morning hours through
this weekend.

&&

.BEACHES...02/102 AM.

A longer period south swell has a moderate chance of producing
strong rip currents Thursday through the upcoming holiday weekend,
with the longest period (17+ seconds) late Wednesday into
Thursday night. A beach hazards statement may be issued to
highlight elevated surf conditions and strong rip current activity
in the surf zone. If planning on heading to the beach Thursday
through the 4th of July Weekend, always swim near an occupied
lifeguard tower and heed their advice/warnings.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...Small Craft Advisory in effect from 3 PM this afternoon to 3
      AM PDT Thursday for zones 650-670-673-676. (See LAXMWWLOX).

&&

$$

PUBLIC...Rorke
AVIATION...Lewis
MARINE...Lewis
BEACHES...Hall/Lewis
SYNOPSIS...30

weather.gov/losangeles

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