Diamond Bar Golf Course California Weather Forecast Discussion

228
FXUS66 KLOX 141646
AFDLOX
Area Forecast Discussion
National Weather Service Los Angeles/Oxnard CA
946 AM PDT Tue Oct 14 2025
.SYNOPSIS...14/930 AM.
A strong storm system will bring widespread rain with isolated
heavy rain and scattered thunderstorms today. There is a
significant risk of debris flows, road flooding, and isolated wind
damage. The rain will diminish and end by late afternoon and
early evening. Dry conditions and warming trend will develop
Wednesday and continue through Saturday.
&&
.SHORT TERM (TDY-THU)...14/945 AM.
***UPDATE***
An unusually strong cold front is moving through Ventura and LA
Counties this morning. It slowed down considerably after rounding
Pt Conception and rain amounts have been impressive, especially
for mid October. Most areas have received at least an inch of
rain, with some as high as 3 inches, mainly in the foothills and
mountains. The slower movement has delayed the departure by at
least a few hours and it may take well into the afternoon to exit
LA County to the east. In the meantime, pockets of severe weather
are possible across LA/Ventura Counties as radars have been
picking up on some rotation. Can`t rule out a small tornado or
waterspout as well as isolated gusty winds up to 60 mph.
Also, the upper low is still just off the coast of southern
Monterey County this morning so some isolated moderate to heavy
showers are still possible with small hail and gusty winds along
the Central Coast through the morning hours at least.
***From Previous Discussion***
The strong cold front assoc with an early season low is currently
draped over the middles of SLO and SBA counties. A strong for
October 100kt jet stream is aligned almost perpendicular to the
main front and this will help move it along. Look for it to move
into and through the City of SBA between 330am and 500 am. The
Front will then enter VTA county around 5am and exit around 8am.
It will then enter LA county around 600 am and exit between 10am.
A tightly wrapped vort lobe is following on the heels of the front
and this will keep the shower and thunderstorm threat going for a
few hours after the main frontal passage.
Rainfall amounts so far have added up to about an inch and half
across SLO county; and inch across most of SBA county; a quarter
to a half inch for the non mtn areas of VTA county and about an
inch across most the counties mtns; LA county has received
anywhere from a tenth to a quarter inch. When all is said done
rainfall amounts should come close to the forecast numbers of
0.75 and 1.50 inches common, except 2.00 to 4.00 inches in the
favorable south facing slopes.
Peak rainfall rates in and near to the front have ranged from .5
to 1.00 inch/hr which is more than enough to create flooding and
debris flows over and near to the 1st and 2nd year burn scars. A
flash flood watch for these burn scars is in effect and people who
live near by must pay close attention to the weather and emergency
officials.
There is an unusual amount of twist in the lower atmosphere and
this along with all of the energy the jet is pumping into the
system and the excellent diffluence aloft has created a very
favorable environment for low topped severe convective storms.
Several severe storms as indicated by doppler weather radar have
already been observed with the front and its likely that it will
produce more as it marches through the rest of the area.
Gusty winds will occur ahead of the front and many areas across
the mtns and deserts will see advisory level gusts from 45 to 55
mph.
Snow will fall at the resort levels (7000+ ft) but will not affect
the major passes.
Lastly Max temps today will only be in the lower to mid 60s or 12
to 24 degrees blo normal - these temps, in fact, would be below
normal for January.
Look for clearing from the west to east during the afternoon and
early evening with dry conditions and mostly clear skies.
Wednesday will be sunny and dry as dry NW flow coming around the
backside of the departing upper low. There will be 5 to 10 degrees
of warming under sunny skies.
Good northerly upper level flow along with moderate offshore flow
from the north develops Wednesday and continues into Thursday
morning. There will be some northerly to northeasterly winds in
the morning but mostly likely under advisory levels. Otherwise
look for continued warming under sunny skies. Max temps will jump
another 5 to 10 degrees.
.LONG TERM (FRI-MON)...14/208 AM.
A little bit of northerly offshore flow along with weak upper
level northerly flow on the back side of a pos tilt trof moving
out of Srn CA will combine to bring some gusty northerly winds to
the mtn canyons and passes. Despite a little cool air advection
from the north max temps will by 3 to 4 degrees under sunny skies.
Max temps will, however, still remain under normals.
Weak ridging aloft along with weak offshore flow will bring
continued sunny skies to all of the area. Upper support and sfc
gradients are weaker than they were on Friday so there will only
be minimal morning winds. Max temps will bump up another 2 or 3
degrees and this will bring max temps up to near normal with
mostly 70s across the csts and 80s in the vlys.
A switch to onshore flow on Sunday will likely bring a return to
the coastal morning marine layer cloud deck. The onshore flow will
also bring 3 to 5 degrees of cooling up and down the csts/vlys.
Long wave troffing will move over the area on Monday bringing more
marine layer clouds and stronger onshore flow. Max temps will fall
4 to 8 locally 10 degrees and end up 6 to 12 degrees blo normals.
&&
.AVIATION...14/1515Z.
At 15Z at KLAX, there was no marine layer or inversion.
For KPRB, KSBP, KSMX, KSBA...Moderate confidence in off and on
again -SHRA through the afternoon, with MVFR/VFR common. There is
a 20% chance of brief RA IFR. 30% chance of LIFR FG 10-16Z at
KPRB.
For KWJF, KPMD moderate confidence in MVFR -RA through early
afternoon then VFR.
For all other airports, moderate confidence in IFR/MVFR common
through the morning. +RA with gusty and erratic winds are
possible at any time. MVFR/VFR -SHRA will follow through
mid-afternoon. Low confidence on exact timing.
KLAX...Moderate confidence in west wind shift happening
1630-1700Z. IFR/MVFR RA will be common through 18-19Z. Low
confidence on other details. After 19-20Z, MVFR/VFR -SHRA through
22-24Z. VFR after.
KBUR...IFR RA will be common through 18-19Z. Low confidence on
other details. After 19-20Z, MVFR/VFR -SHRA through 22-24Z. VFR
after. 20% chance of LIFR FG 10-16Z.
&&
.MARINE...14/749 AM.
A significant storm system will be focused over Ventura, Los
Angeles, and Orange Counties through the morning with gusty and
erratic winds and heavy rain. Waterspouts remain possible. For the
rest of the waters, and all areas by the afternoon, off and on
again showers and generally west to northwest winds will prevail
into tonight.
Small Craft Advisory (SCA) northwest winds are likely for the
waters from the Central Coast the San Nicolas Island Wednesday
afternoon through Thursday Night.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
CA...Flood Watch remains in effect until 3 PM PDT this afternoon
      for zones
      38-88-342-344-345-348-353-355-358-362-368>375-377>380-548. (See LAXFFALOX).
     Wind Advisory in effect until 2 PM PDT this afternoon for
      zones 376>383. (See LAXNPWLOX).
PZ...Small Craft Advisory in effect until noon PDT today for zones
      650-673-676. (See LAXMWWLOX).
     Small Craft Advisory in effect until 3 PM PDT this afternoon
      for zone 655. (See LAXMWWLOX).
&&
$$
PUBLIC...MW/Rorke
AVIATION...RK
MARINE...RK
SYNOPSIS...RK/CC
weather.gov/losangeles
Experimental Graphical Hazardous Weather Outlook at:
https://www.weather.gov/erh/ghwo?wfo=lox

NWS LOX Office Area Forecast Discussion