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AGUS76 KRSA 081435
HMDRSA

Hydrometeorological Discussion
National Weather Service / California Nevada RFC / Sacramento CA
730 AM PDT Wed May 8 2024

...WARMING THROUGHOUT THE WEEK AS HIGH PRESSURE BUILDS OFFSHORE...
...GENERALLY DRY CONDITIONS ASIDE FROM ISOLATED SHOWERS/T-STORMS
OVER NV THURS, THE SIERRA AND NV FRI AFTN/EVE & SUN/MON...

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

A large upper low resides over the north central US this morning
with building high pressure over the eastern Pacific. The low will
begin to separate later today with the back half breaking off and
retrograding back towards CA/NV into Thursday. This will push the
southern half of the ridge offshore while the northern half wraps
around into the PacNW. This may generate some isolated showers and
thunderstorms in the afternoons/evenings, mainly over north/east NV.
The upper low will back into NV on Friday with the core of the
system over srn NV. This will bring better chances of isolated
showers and thunderstorms in the afternoon/evening with the best
chances east of the Sierra. Friday night, the low will shift its
trajectory eastward pulling out of the region on Saturday and
allowing the ridge to move back in. Models then show a weak trough
developing west of CA throughout Sunday impacting the region through
the rest of the period. There are some differences between the
models and amongst the ensembles as to the relative strength and
positioning of this troughing. Depending on how strong the offshore
ridging is and how much influence the trough has, there is a chance
of some isolated showers Sunday and Monday, mainly over the Sierra
and into NV. In either case, no significant precipitation is
anticipated as the official QPF for days 1-6 has at most 0.10-0.25"
over the Sierra and generally a few hundredths to a tenth of an inch
under any other areas that receive showers. Locally higher amounts
possible should any thunderstorms develop.

The large upper low over the north central US will keep temperatures
moderated today at 5-15 deg F below normal for most of the region
with some warmer temperatures over the coast thanks to the offshore
ridge. Warming from west to east is then expected the rest of the
week and into the weekend as high pressure builds offshore. Northern
and central coastal CA can expect above normal temperatures
beginning tomorrow with these conditions spreading across the region
the rest of the week. Expecting widespread above normal temperatures
Friday through Monday by 5-10+ deg F (most prominent away from the
coast).

Freezing levels 6-8 kft over NV today and 7-12.5 kft over CA with
higher freezing levels spreading across the region the rest of the
period. Generally 8-12 kft the rest of the week with the region
generally above 10 kft by Saturday remaining around 10-12 kft the
rest of the period.


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



AS

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