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AGUS76 KRSA 251320
HMDRSA

Hydrometeorological Discussion
National Weather Service / California-Nevada RFC / Sacramento CA
620 AM PDT Fri Sep 25 2026

...PRECIP WRAPPING UP OVER FAR NW CA AND SW OR...
...INCREASING PRECIP CHANCES SRN NV AND SE CA FOR SUN-TUE...

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

Overnight precip was limited to coastal areas from Cape Mendocino
northward and inland over portions of the upper Klamath River basin.
Best amounts were across the Smith River basin with precip gauges
showing totals near or just over 1.00-inch. This is all courtesy of
a s/wv trof currently approaching the Pacific Northwest and far
northern CA coast with a sfc cold front out ahead of this feature
moving eastward. As the s/wv trof lifts off toward the northeast
today...look for any scattered light precip to come to an end.

Attention next turns to a subtle feature making its way across 160W
this morning just below 50N. This disturbance will race eastward to
approx 130W before slowing down and digging to the southeast as it
forms a cutoff low. For Sunday...look for the circulation to reach
the SF Bay Area before swinging inland across central CA on Monday
before exiting the region across the lower Colorado River basin on
Tuesday. Initially...precip is expected to be rather scattered on
Sunday with some scattered light precip over portions of western NV
and far southern CA near the MX border. However...models are showing
just enough tropical moisture making its way northward on the
downstream side of this feature...reaching the southeast CA deserts
and southern/eastern NV with PW values surpassing 1.25-inches and
potentially even higher. This will help fuel more widespread precip
with amounts of 0.25- to 0.75-inch (locally higher under any
stronger convective cells) on Monday into early Tuesday.

As this system exits to the east...high pressure will build along
the west coast for the middle of the week...bringing dry conditions
to the region.


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



DRK

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