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Hydrometeorological Discussion
National Weather Service / California-Nevada RFC / Sacramento CA
715 AM PST Fri Nov 13 2026

...SERIES OF SYSTEMS TO IMPACT THE REGION INTO NEXT WEEK...

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

Two areas of precip straddling the coast this morning with the more 
impressive negatively tilted s/wv trof making its way toward the 
Pacific Northwest and northern CA coast...while a more compact 
disturbance is just off the southern CA and northern Baja coast. 
Radar imagery shows one solid line of precip making its way onshore 
along the north coast down to about Point Arena at the 13/15Z hour 
with several embedded lines of convective precip just ahead of the 
offshore cold front. Down south...the line of showers and 
thunderstorms moving onshore from about Orange and San Diego 
counties...but has shown a tendency to weaken as it continues to 
move toward the east. However...precip amounts over coastal southern 
CA with the onshore flow has brought widespread precip slightly 
higher than originally anticipated.

Through the morning and afternoon hours...the s/wv trof moving 
toward the Pacific Northwest and northern CA coast will dig a bit 
more to the southeast before crossing inland. This will push the 
associated cold front inland...while displacing the moisture plume 
of approx 1.00-inch PW to the south and east. Heaviest precip will 
shift from the northern CA coast this morning to the northern and 
central Sierra back to the coast over the SF Bay Area down to 
Monterey County. After sunset and through the overnight...look for 
the system to continue to track inland before exiting the area to 
the east around sunrise. Precip will focus on the southern Sierra 
back southwest to near Point Conception during the evening and then 
finally eastern NV down to the coast between Los Angeles and San 
Diego.

The majority of Saturday looks to be a break day between systems as 
a transitory upr ridge slides across the area ahead of the next s/wv 
trof riding east between 40N and 50N...on its way to the west 
coast...where it is anticipated to dig southward before shifting 
inland. Some timing difference amongst the models with both the 
13/00Z and 13/06Z GFS lagging on the speed of the cold front across 
the region...while the 13/00Z EC is the quickest. The 13/00Z CMC is 
somewhere in between the two. For now...used the more compromise 
solution...which was supported by the latest WPC QPF. Precip will 
slide across northern CA from Sunday morning into the evening hours 
as the overall system slowly makes its way across the area...finally 
shifting toward central CA and weakening during the overnight hours 
into Monday morning. This thinking across central and southern CA is 
slightly different from yesterday...bringing a decrease to overall 
amounts on later Sunday into Monday. 

This second late weekend into Monday system will shift east of the 
area on Tuesday...while the region awaits the next system that is 
showing the lowest confidence in the track and strength. The s/wv 
trof looks to move toward the Pacific Northwest during the middle of 
the week...but then how the system evolves is up in the air. The EC 
is wanting to dig the system farther inland more over the Great 
Basin...while the GFS is wanting to drop the system south closer to 
the west coast. The CMC is somewhere in between...but overall is 
looking closer to the EC at this time. For now...a compromise 
approach was used with the NBM50Pct being included in a blend with 
the GFS and EC. 

Freezing levels are currently from 8000- to 10000-feet across the 
region...mainly from west to east. As the core of the system moves 
overhead later tonight...these will bottom out from 5500- to about 
7000-feet for the northern tier of the region...before bouncing back 
with the upr ridge moving in on Saturday. The later weekend and 
Monday system will bring in some more cooler air across the majority 
of the region...dropping to 4500- to 7500-feet from north-to-south 
before fluctuating a bit from Tuesday into Wednesday from 4500-feet 
north to 10000-feet south.


Please Note: This product may NOT be routinely updated.
Please refer to the following product issued by the CNRFC
www.cnrfc.noaa.gov/Daily-Briefing for a graphical summary of
weather and hydrologic conditions.