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Hydrometeorological Discussion
National Weather Service / California Nevada RFC / Sacramento CA
110 PM PST Fri Nov 14 2025

...MODERATE TO LOCALLY HEAVY PRECIP THRU SAT DUE TO A LARGE LOW 
CARRYING TROPICAL MOISTURE INTO THE REGION, T-STORMS ACROSS PARTS OF 
SRN CA TODAY/TOMORROW...
...WET PATTERN CONTINUES FOR NEXT WEEK AS ADDITIONAL SYSTEMS MOVE IN 
FROM THE NW...

.METEOROLOGICAL CONDITIONS (FRI PM - THU AM)...

Tropical moisture continues to surge into srn CA and up the SJ 
valley into the Sierra this afternoon. Radar and satellite show 
precip from coastal soCal northward to about I-80. Hot spots over 
the past 6 hours have been over the hills of Santa Barbara/Ventura 
counties with observations showing about 1-2.50+" and 0.50-1"+ over 
the central Sierra. The main focus of the afternoon update has been 
for the next 24 to 48 hours particularly over srn CA. Increased QPF 
in the current period (to 00z) over the Transverse a bit given 
observations. The moisture plume will shift a bit further south 
later today before expanding back northward along the coast tonight 
and tomorrow morning when more moderate to locally heavy precip will 
return where things have moved out this afternoon. Time frame for 
heaviest precip generally 12z Sat-00z Sun. Uncertainty remains on 
how far north the moisture will regress and how much precip will 
accompany it. The GFS and now the NAM continue to be a good deal 
wetter than the ECMWF over San Diego County tonight through tomorrow 
morning, but the ECMWF has trended a bit wetter as has WPC/NBM.   

The low will rotate offshore the rest of today making its way south 
off the coast. Models are sending the low eastward later tomorrow 
towards the coast and moving it inland from sw to ne in the late 
afternoon and overnight. The GFS/ECMWF still show a little embedded 
feature forming off the southern edge of the low's core early Sunday 
with a band of precip, but the intensity of that has reduced in the 
12z runs. Looking at the individual members of the ECMWF AIFS, I 
still see that feature in several members with at least a few 
sending that heavier precip into San Diego Sunday morning, so it is 
worth keeping an eye on. For now, the forecast is on the drier side 
at about 0.25" for Sunday morning. Overall, QPF has changed on the 
order of 0.10-0.50" up or down for most areas. The exception being 
the models trending down a bit over the Transverse mountains 
overnight tonight by nearly 1". Blended in the latest NBM/WPC and 
the 12z GFS/ECMWF. QPF through 12z Sun:  1-4" central/southern 
Sierra, 3-6" Transverse, 2-4" coastal srn CA, 0.10-0.75" Bay Area, 
0.50-1.50" central coast/SJ valley, and generally 0.10" or less for 
far nrn CA.

The system will start to lift out of the area later Sunday with the 
next trough right behind it approaching from the northwest. 
Disagreement remains on the fate of that next system and the one 
after that so still a good amount of uncertainty in the QPF for the 
extended. Bottom line, expect a wet pattern to continue into next 
week with at least a pair of additional systems.