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Hydrometeorological Discussion
National Weather Service / California Nevada RFC / Sacramento CA
840 AM PDT Thu Jun 4 2026

...WARM AND DRY THROUGH FRIDAY...
...TURNING COOLER THIS WEEKEND INTO EARLY NEXT WEEK...
...PRECIP CHANCES INCREASE FOR NORTHERN CA AND NORTHERN NV MON-TUE...

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

The s/wv trof that moved across the Pacific Northwest yesterday has 
shifted off toward the east and is now making its way across the 
northern Rockies this morning. The deep upr low over the northeast 
Pacific has shifted a bit to the east as well and now currently 
resides in the vicinity of 52N/138W. At the same time...the upr 
ridge to the southwest of the CA coast is building across the region 
and will bring dry and above average temperatures for the next 
couple days...peaking on Friday. Anomalies are currently expected to 
be anywhere from plus 5- to plus 20-degF over seasonal normals for 
afternoon high temperatures. 

By this weekend...the system over the northeast Pacific will slowly 
make its way eastward and become a bit more elongated...bringing 
troffing to the west coast. This will result in temperatures cooling 
and initially some scattered light precip from the southern Sierra 
up toward northeast NV on Saturday and Sunday. 

As this system rotates inland later Sunday...the next disturbance 
making its way across the Pacific will replace this first one. 
Also...this feature will have a tap into some lower latitude 
moisture that is advecting northeast over the central Pacific into 
the mid-latitudes and then riding east generally just north of 40N. 
This moisture plume actually has some impressive PW values that are 
over 2.00-inches initially...and around the 1.00-inch mark as it 
intersects the west coast early on Monday from the SF Bay Area up to 
about Cape Mendocino. Models are continuing to hint at an increasing 
chance of widespread light to moderate precip mainly over areas from 
I-80 northward on Monday into Tuesday. The latest NBM is picking up 
on this precip as well...and for the morning forecast was used with 
a blend of the 04/00Z EC and latest WPC QPF. This brings totals of 
0.25- to 0.75-inch over the higher terrain of northern CA and the 
southern OR Cascades...as well as 0.10- to 0.33-inch for wetter 
locations of northern NV. 

This feature will slowly move out through the middle of next week 
with an upr ridge building over the eastern Pacific nudging toward 
the west coast the following weekend. 

Freezing levels today into tomorrow will range from 13000-feet for 
areas near the CA/OR border to 17000-feet for central and southern 
CA. These will dip this weekend with the arrival of the first system 
along the west coast...down to about 8000- to 10000-feet near the 
CA/OR border to 15500-feet close to the CA/MX border. Then as the 
second system arrives...these will drop a bit more for areas near 
the CA/OR border from 6500- to 8000-feet...but remain relatively 
elevated across central and southern CA.


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.