Hydrometeorological Discussion
Issued by NWS California-Nevada RFC

364
AGUS76 KRSA 211306
HMDRSA

Hydrometeorological Discussion
National Weather Service / California-Nevada RFC / Sacramento CA
605 AM PDT Mon Sep 21 2026

...SCATTERED SHOWERS TODAY CENTRAL/SOUTHERN SIERRA AND SOUTHERN NV...
...LIGHT PRECIP FAR NORTHWEST AREAS LATER THU INTO FRI...

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

An area of low pressure is slowly drifting eastward...currently
located near Point Conception this morning. Already some scattered
showers associated with this feature are moving from southwest to
northeast on the downstream side over the southeast CA deserts. By
this afternoon...the primary circulation will be situated over the
southern San Joaquin Valley with the best opportunity for precip
development in the northeast quadrant of the low pressure where
diffluent flow aloft will be best. Look for showers and t-storms
over the central/southern Sierra and points east across southern NV.
Into the evening and overnight hours...the low pressure will
increase its forward speed to the northeast and exit the area over
the UT/NV border early Tuesday.

For later Tuesday through early Thursday...drier southwest flow will
become the rule across CA and NV. Then by later Thursday into Friday
a s/wv trof will reach the Pacific Northwest and clip areas near the
CA/OR border with light precip possible mainly along the the coast
down to Eureka...and inland over the crest of the southern OR
Cascades. Amounts look to be near or less than 0.25-inch. Then as
this system quickly shifts off toward the east-northeast...flow will
once again turn southwest with a drier airmass in place.


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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