664 

FXUS66 KLOX 301751

AFDLOX



Area Forecast Discussion...UPDATED

National Weather Service Los Angeles/Oxnard CA 

951 AM PST Tue Dec 30 2025



Updated Aviation Section



.SYNOPSIS...30/1216 AM.



The Santa Ana winds will continue today under mostly cloudy skies.

High temperatures will end up in lower 70s for most of the coasts

and valleys. A new storm will move into the area from the south 

Wednesday with periods of rain through at least Saturday, heaviest

Wednesday night into New Years Day.



&&



.SHORT TERM (TDY-THU)...30/822 AM.



***UPDATE***



Latest satellite and surface observations indicate mostly cloudy

skies across the area as a broad sheet of high clouds drifts

overhead. Santa Ana winds continue across the area with gusts in

the 35-55 MPH across Ventura and LA counties.



Forecast-wise for the immediate short term, no significant issues

are expected. Santa Ana winds will peak in strength this morning

then gradually diminish this afternoon. Current WIND ADVISORIES

run until 300 PM this afternoon which looks good and they will

likely be allowed to expire at 300 PM. As for temperatures, it

will definitely be a mixed bag, due to the presence of the blanket

of high clouds. Temperatures should be a bit cooler along the

coast and a bit warmer inland with the weaker offshore flow today.

However, the cloud cover will likely impact those expected trends.

Also, some sprinkles have been reported across the area. So, have

added 15% chance POPs to all areas through the day. Any amounts

will be trace to only a couple hundredths of an inch. 



Overall, forecast looks good for the immediate short term. So, no

significant updates are expected other than adding 15% POPs to all

areas. For the afternoon forecast suite, attention will turn to 

New Year Eve/Day storm. 



***From Previous Discussion***



A fairly unusual day with a moderate Santa Ana and mostly cloudy

skies. This morning there will about a 7mb offshore push from the

east and about 4mb from the north. The upper support is weaker

than ydy but still there will be enough to produce advisory level

gusts in the wind prone areas through early afternoon.

Temperatures this morning across the windy areas are still in the

mid 60s while the wind sheltered areas have much lower temps since

the dry air cools so quickly. For example Van Nuys is currently 

63 degrees and Burbank, only a few miles away, is 54 degrees. At 

the same time a large layer of cirrus clouds is spinning off an 

upper low to the SW of LA. These clouds will make the day a mostly

cloudy one. The current forecast calls for some coastal cooling 

due to slightly weaker offshore flow and warming across the 

interior due to much less cool air advection. The clouds could 

throw a monkey wrench into the temp fcst however if they come in 

thicker than fcst - the warming would be much less or even turn 

cooler.



Wednesday will be an interesting day. The offshore flow will

continue albeit only half a strong as it is today. The

aforementioned upper low will move northward and spin a large 

lobe of PVA over the area. A slight chance of rain will develop in

the predawn hours. In the morning rain will become likely across 

the Central Coast (~70 percent chc) with a 30 to 40 percent chc 

south of Point Conception. The vort lobe will cover the entire 

forecast area during the afternoon and all areas should see some 

rain. The really juicy air will still be south of the area so 

rainfall totals and rates will not be that high. Also the 

downsloping drying offshore flow will also diminish the rainfall. 

Rainfall totals for the day should come in between a quarter inch 

and three quarters of an inch. Max temps will fall with the 

thicker clouds and reduced offshore flow. Max temps across the 

csts/vlys will fall 3 to 6 degrees and maybe more if the rain 

arrives earlier.



PWATs rise quickly to about 1.25" Wednesday night and as high as 

1.5" New Years Day. At the same time the upper pivots to the east

and moves across SBA/VTA/LA counties through the day. This track

will bring plenty of south winds to help with the orographic

rainfall. The heaviest rain will occur from midnight to noon

across areas south of Point Conception. From midnight to dawn

cst/vlys will likely recieve .50"-.75" inches of rain while the

mtns and foothills see .75"-1.25". From dawn to noon about an

additional half inch will fall on southern SBA and VTA counties.

The csts/vlys of LA county will likely another .50"-.75" inches 

of rain while the mtns and foothills see .75"-1.25". The Central 

coast will see much less rain likely between .50 and .75 for the 

entire day. Rain will be much lighter in the afternoon with only a

quarter to a third of an inch of rain fcst. In total from 

Midnight to late evening rainfall should be 1.25" to 1.75" locally

2" for the csts and vlys and 2 to 4 inches for the foothill and 

mtns. Rain rates should peak at around 0.5" per hour, with 

isolated rates up to 0.75" per hour. The higher rates will be 

south of Pt Conception and across the upslope areas. Due to the 

large amount of rain that fell last week, there will be much more 

runoff than usual and flood watches will be strongly considered 

over the next 24 hours, particularly in light of the slight risk 

of excessive rainfall from WPC.



There is a near 100 percent chc of a wet New Years Parade as well

as the overnight hours leading up to it (which will affect people

camping out before the parade). The last wet New Year's parade 

was in 2006.



There is quite a bit of lightning with the core of the storm now

and the chc of TSTMs will have to be monitored as the low

approaches. Right now the chc of a TSTM is about 10 percent but

this could rise if the upper low keeps churning out lightning. 

Winds will not be as strong with gusts only to 40 mph expected at

the storms peak. Since this storm moisture south and flow is from

the south, snow levels will be over 9000 feet.



.LONG TERM (FRI-MON)...30/1214 AM.



Moist SW flow will set up over the area on Friday. There will

likely be plenty of clouds. Some energy will move down the coast 

and will trigger a 60 percent chc of rain across the Central Coast

and around a 30 percent chc south of Pt Conception in the 

morning. Rain is almost a certainty for the Central Coast in the 

afternoon and a 50 to 60 percent chc or rain will develop south of

Pt Conception. Rainfall amounts will not be too great under a

half inch and likely under a quarter inch south of Pt Conception.

Max temps will end up in the lower to mid 60s for most of the

csts/vlys.



A cold front will work its way from the northwest to the NE 

Friday night and Saturday morning. Steady rain is likely for most 

of the area as the front sweeps across. The steady rain will end 

in the afternoon and turn to scattered showers in the wake of the 

front. Snow levels will start out around 7500 ft and will lower 

to 6500 feet in the afternoon. This system is not very moist or

dynamic and rainfall amounts should not be too concerning. Right

now it is forecast to drop a quarter to a half inch across the

csts/vlys and a half inch to an inch across the coastal slopes and

foothills. Max temps, again, will end up in the lower to mid 60s 

for most of the csts/vlys.



Moist SW flow continues Sun and Mon. There are a multitude of mdl

solutions that have rain developing at various different time.

Because of this there is a chc of rain all through the period.

This is mostly representative of the blended mdl smearing effect 

rather a forecast of 60 hours of rain. So it is very likely that 

it will rain a times during the period but there will also be dry 

periods. Another quarter to a third of an inch of rain is 

possible over the two and a half day period. Little change in 

temps on Sunday and perhaps a couple degrees of warming on Monday.



&&



.AVIATION...30/1750Z.



At 1718Z at KLAX, there was a shallow surface inversion to 900 

feet with a temperature of 21 degrees Celsius. A secondary 

inversion was topped at 1800 with a temperatures of 21 degrees 

Celsius.



Moderate confidence in TAFs. N to NE winds will continue to 

impact KOXR and KCMA through the period. Then higher confidence in 

and more widespread E to SE winds across all terminals just after 

31/18Z. Strongest winds likely for Santa Barbara and San Luis

Obispo Counties, but moderate winds possible elsewhere.



SHRA is possible today, then rain chances increase after 31/12Z.

Most intense rain will fall sometime between 01/06Z and 03Z/00Z,

with heaviest rain expected south of Point Conception. Slight

chance for -TSRA after 01/06Z, especially south of Point 

Conception.



Light to moderate turbulence and LLWS is likely over and near 

mountainous terrain, especially across Los Angeles and Ventura 

counties through the forecast period. More widespread turbulence 

and LLWS likely after 31/18Z.



KLAX...Moderate confidence in TAF. -SHRA possible today, but 

chances for measurable rain increase after 31/15Z. Slight

chance for -TSRA as early as 01/06Z. High confidence in winds 

remaining northeast to east through the period. Stronger winds are

expected after 01/00Z (gusts up to 20 knots), but there is a 30% 

chance for east to southeast winds to reach 15 knots by 31/20Z. 

Best chances for east wind component below 8 knots is between 

31/05Z and 31/10Z.



KBUR...Moderate confidence in TAF. -SHRA possible today, but 

chances for measurable rain increase after 31/16Z Wed.



&&



.MARINE...30/833 AM.



Small Craft Advisory (SCA) level Santa Ana winds from the 

northeast will continue to impact portions of the inner waters 

south of Point Conception through the remainder of the day, 

including nearshore areas from Ventura south through Malibu. 

Localized Gale Force gusts to 35 knots may occur, especially 

through later this morning. 



Another round of SCA level Santa Anas is possible (40-50% chance)

beginning Wednesday morning across typical areas, but confidence 

is higher in widespread SCA level winds from the southeast 

impacting the region as early as Wed afternoon and continuing 

through at least late Wed night as another storm makes its 

presence felt across the region. There is a 20% chance for Gale 

Force Winds during this period. A relative lull is possible 

Thursday, but a return of SCA level south to southwest wind is 

likely Friday into Saturday, especially north and west of Point 

Conception as a cold front moves through the area.



A steep and choppy southerly wind swell will accompany the winds,

peaking Wednesday night into Thursday. Come Friday, a west to

northwest swell will accompany the secondary storm coming through.

This swell will be larger and longer period.



Rain will likely be heaviest Wednesday (New Year's Eve) night

through Thursday (New Year's Day). There is a slight chance of 

thunderstorms during this period, but confidence is low in timing.

Waterspouts, gusty and erratic winds, frequent lightning, and

heavy rain are all possible with any thunderstorm.



&&



.LOX WATCHES/WARNINGS/ADVISORIES...

CA...Wind Advisory remains in effect until 3 PM PST this afternoon

      for zones 88-354-355-358-362-369>376-378>380. (See LAXNPWLOX).

PZ...Small Craft Advisory in effect until 9 PM PST this evening

      for zones 650-655. (See LAXMWWLOX).



&&



$$



PUBLIC...Rorke

AVIATION...Lewis

MARINE...Lewis

SYNOPSIS...MW



weather.gov/losangeles



Experimental Graphical Hazardous Weather Outlook at:

https://www.weather.gov/erh/ghwo?wfo=lox