...A FEW SIERRA AND EASTERN NV SHOWERS TODAY INTO FRI...
...LOW PRESSURE MOVING IN FOR THE WEEKEND INTO EARLY NEXT WEEK...

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

A narrow wavelength upr ridge stretches from the eastern Pacific
just off the CA coast toward the north-northeast reaching over
western Canada. Over the interior...cyclonic flow aloft is situated
across the Great Basin and and Rocky Mountain states. Models do hint
at light precip developing over the southern Sierra as well as
eastern NV...but with little if any developing yesterday in a
similar flow regime...not overly confident on anything forming in
the way of measurable precip later this afternoon and early evening.

The more interesting feature of note is a s/wv trof approaching 140W
over the northeast Pacific this morning. Look for this feature to
make its way just off Vancouver Island and the Pacific Northwest as
the the upr ridge slides inland tomorrow. As this occurs...there may
be some scattered precip developing over the northern CA coastal
mountains...and the crest of the southern OR Cascades during the
afternoon and early evening hours. In fact...SPC does draw an area
of general thunderstorms in their Day 2 Convective Outlook for these
locations. Then...into the weekend this disturbance will form a
cutoff low and slide southward along or just inside of 130W before
settling just west of the central CA coast.

For Saturday...scattered showers and thunderstorms will be possible
in the northeast quadrant of this upr low...in an area of diffluent
flow aloft. This looks to set up over the upr Klamath River
basin...northeast CA Plateau...and the northern/central Sierra. The
SPC Day 3 Convective Outlook does highlight these areas with the
potential for general thunderstorms. The better day of the weekend
for more widespread precip will be on Sunday as the upr low starts
to drift closer to the coast and reaches 125W at the latitude of
Monterey during the afternoon hours. Models area showing the best
precip setting up from the Trinity Mountains east across the Shasta
Lake drainage and then down much of Sierra with the focus being the
northern and central portions. Light precip will be possible into
the northern two-thirds of NV.

On Monday...the upr low continues its slow track and finally starts
to make its way inland across central CA. The best precip is still
anticipated to fall over the northeast quadrant of this
feature...which continues to focus on the Trinity Mountains east
over the Shasta Lake drainage and northeast CA Plateau along with
stretching down the northern/central Sierra as well as western NV.
Finally by Tuesday...the system will weaken and begin to move off
toward the east with scattered light precip remaining over the
Sierra and portions of northern/eastern NV. Behind this
system...look for an upr ridge to begin to move toward the west
coast with warmer and drier conditions on tap for the rest of the
next week.

Freezing levels are currently ranging from 8500-feet over northeast
NV to 11500-feet along coastal locations. As the high pressure ridge
slides overhead on Friday...look for freezing levels to range from
10000-feet northwest to 13000-feet along the CA/MX border.
Then...with the upr low moving toward the region...look for freezing
levels to initially drop along coastal sections on Sunday down to
about 9500-feet...but still elevated inland. By Monday into Tuesday
with the upr low moving across the region...the core of the system
will bring freezing levels down to about 7500-feet for central
CA...but slightly higher elsewhere away from the primary circulation.

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.