722 FXUS66 KLOX 141031 AFDLOXArea Forecast Discussion National Weather Service Los Angeles/Oxnard CA 331 AM PDT Tue Oct 14 2025
.SYNOPSIS...14/146 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)...14/331 AM.
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...14/0614Z.
At 0544Z at KLAX, there a was 8800 ft moist layer.
Low confidence in the TAFs. A strong cold front will pass through the area and will exit LA county around noon on Tuesday (14/20Z). Strong south winds ahead of the front will create areas of TURBC over and near to hier trrn.
Both Cigs and Vis will vary frequently as the front nears passes over every site. Ocnl IFR cig/vis is likely under heavier showers and/or TSTMs. There is a 30 percent chc of TSTMs with the front and a 20 percent chc during the afternoon behind the front.
KLAX...Low confidence in TAF. Cigs and Vis will vary frequently 08Z-20Z. There is a 30% chance of a thunderstorm from 12Z to 18Z Tue. There is a 25 percent chc of ocnl 2SM ovc008 conds 12Z-18Z. High confidence in a 12-18 kt east wind component 13Z-17Z.
KBUR...Low confidence in TAF. Cigs and Vis will vary frequently 08Z-20Z. There is a 30% chance of a thunderstorm from 12Z to 18Z Tue. There is a 25 percent chc of ocnl 2SM ovc008 conds 12Z-18Z.
&&
.MARINE...14/225 AM.
Through this afternoon, a storm system and associated cold front will move across the region. This will bring a 20-40% chance of thunderstorms to all of the coastal waters during that timeframe. Any thunderstorms that form may be capable of frequent cloud to surface lightning, gusty and erratic winds with locally higher, choppy seas, small hail, and even a waterspout. Please see the latest Marine Weather Statement (LAXMWSLOX) for further details.
For the outer waters and inner waters N of Point Sal, Small Craft Advisory (SCA) level south winds are expected (60%-70% chance) with the cold front this morning, then decreasing from the west behind the front this afternoon and evening. Wednesday through Thursday increasing NW winds will likely reach SCA levels once again. Best chances south of Point Conception. Conds should then be below SCA levels Friday through Saturday night.
For the inner waters south of Point Conception, S to SW winds at SCA levels are expected across the area through this morning as the front moves through the region. There is a 50% chance of Gale Force winds over these waters through mid morning. The strongest winds will be north of Santa Cruz and Anacapa Islands and along the coast from Point Mugu to Point Dume. Conds should then be below SCA levels Tuesday night through Saturday night.
&&
.LOX WATCHES/WARNINGS/ADVISORIES... CA...Wind Advisory in effect until 8 AM PDT this morning for zones 38-342>345-351>353. (See LAXNPWLOX). 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 9 AM PDT this morning for zone 645. (See LAXMWWLOX). Small Craft Advisory in effect until 3 PM PDT this afternoon for zones 673-676. (See LAXMWWLOX).
&&
$$
PUBLIC...Rorke AVIATION...Rorke MARINE...Sirard/Ciliberti 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