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AGUS76 KRSA 061426
HMDRSA

Hydrometeorological Discussion
National Weather Service / California Nevada RFC / Sacramento CA
730 AM PDT Mon May 6 2024

...SCATTERED SHOWERS AND ISOLATED T-STORMS ALONG THE NRN REGIONAL
BORDER AS A DISTURBANCE MOVES THROUGH THE PACNW TODAY INTO TUES...
...WARMING TREND KICKS OFF TOMORROW WITH DRY CONDITIONS THEN
EXPECTED THE REST OF THE PERIOD, TEMPS 5-10+ DEG F ABOVE NORMAL INTO
THE WEEKEND...

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

Observations report another 0.50-1" or so over the northern/central
Sierra over the past 24 hrs and scattered amounts across the rest of
the region ranging from a few hundredths to over 0.50". The upper
low that has been moving through over the weekend has opened into a
trough and exited into WY/UT/CO. Weak ridging is attempting to build
in over CA/NV as another trough arrives offshore of the PacNW. The
trough will move through OR/WA today digging into the northern CA/NV
borders potentially generating some showers and isolated
thunderstorms. This system will enter ID into Tuesday as the
currently exiting low re-strengthens over the north central US. The
continued presence of troughing over the PacNW and nrn NV will keep
showers going Tuesday morning along the northern CA/NV borders while
high pressure building offshore keeps the rest of the region dry and
kicks off some warming. Afternoon high temperatures expected to
remain about 5-15 deg F below seasonal normals today.

Later Tuesday, the trough will merge with the low back east to form
a larger system as high pressure continues to attempt to gain a
foothold into the west coast. This pattern of low pressure to the
northeast and high pressure to the west will persist mid-week
keeping conditions dry and gradually rising temperatures from west
to east. Into Thursday, the low will split in two with the western
system retrograding back over the region pushing the ridge offshore.
The low will remain centered around NV into the Four Corners the
rest of the work week as the ridge sneaks around into the PacNW. By
Friday afternoon, the low looks to move further away allowing high
pressure to build into CA resulting in more widespread above normal
temperatures by 5-10 deg F. Heading into the weekend, high pressure
will continue to push into the west coast while the low retreats
further away. The result will be above normal temperatures across
the region by 5-15 deg F and mostly dry conditions.

All of the precip in the current forecast is expected today through
Tuesday morning and should be confined to far northern CA/NV and srn
OR. Highest amounts along the crest of the Cascades at 0.50-1" with
0.10-0.50" over the Smith Basin and generally a few hundredths to a
tenth of an inch or so elsewhere. No more precip expected after then
aside from a stray shower or two late this week as the low backs
into NV. The system moving through the PacNW today will keep
freezing levels over the northern part of the region down to 5-7 kft
with 8-13 kft for the rest of the region. Levels up north will lower
further into Tuesday morning reaching a min of 3.5-7 kft before
higher levels spread. most of CA is forecast to be at 8-12.5 kft
from nw to se before the entire region rises above 10 kft later
Friday.


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



AS

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