436
AGUS76 KRSA 092121
HMDRSA

Hydrometeorological Discussion
National Weather Service / California Nevada RFC / Sacramento CA
120 PM PST Tue Dec 9 2025

...MOSTLY DRY CONDITIONS THROUGH THE PERIOD AS THE REGION REMAINS
UNDER THE INFLUENCE OF STRONG HIGH PRESSURE...
...OCCASIONAL SHOWERS OVER THE SRN OR CASCADES TODAY AS TROUGHS
IMPACT THE PACNW, AND MIST/DRIZZLE POSSIBLE DOWN THE VALLEYS AT
NIGHT/EARLY AM AS LOW CLOUDS AND/OR FOG PERSIST...

.METEOROLOGICAL CONDITIONS (TUE AM - MON AM)...

No major changes to the afternoon forecast. The weather for CA/NV
continues to be primarily driven by a strong ridge of high pressure
overhead and into the eastern Pacific. Low clouds plague the central
valleys still as well. This pattern is expected to persist through
the period with late night/early morning mist/drizzle possible down
the valleys and dry conditions most elsewhere. Showers over the srn
OR Cascades through early tomorrow producing about 0.10-0.30" of
precip. Looking at the longer range forecast, the ECMWF and the CMC
want to bring in a system to nrn CA right after the current six day
window ends while the GFS remains unmoving in its insistence on
keeping the ridge around longer. The GFS does show a similar system
but has it further to the north, thanks to the ridge, resulting in
only lighter accumulations along the north coast vs precip extending
potentially down to I-80 should the CMC or ECMWF solution manifest.


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.

QPF graphics are available at www.cnrfc.noaa.gov/qpf.php



AS

$$