000
FXUS66 KSTO 292119
AFDSTO

Area Forecast Discussion
National Weather Service Sacramento CA
219 PM PDT Wed Mar 29 2023


.SYNOPSIS...
Showers and thunderstorms expected today with light snow
showers continuing in the mountains. Drier weather expected
Thursday and Friday. Precipitation chances return over the weekend
and persist into next week.
&&

.Discussion...

The low will remain just off the coast as it moves southeast
today, reaching the central coast of California by late this
evening. Several bands of showers will continue to rotate through
the region today with some embedded thunderstorms possible mainly
from I-80 southward. However, confidence on thunderstorm chances
have decreased with significant cloud cover inhibiting sufficient
instability to develop to produce thunderstorms. Mesoanalysis is
still indicating the better instability will be mainly focused
across San Joaquin Valley, where there is more scattered clouds.
If thunderstorms do develop, the main impacts will be breif heavy
rain, small hail and gusty winds. Rainfall rates have trended down
in recent CAMs and generally look to remain less than 0.25-0.50"
per hour, limiting the threat of localized flooding.

Showers will taper off from the north tonight as the low shifts
further south. Besides some lingering light snow showers in the
mountains, expect mostly dry conditions Thursday as we`ll be under
mostly dry northwest flow.

Brief, short-wave ridge will develop Friday keeping drier
weather in the forecast. Below normal temperatures will continue
with Valley high temperatures in the upper 50`s to near 60
degrees.

The next system moves into far northern California Saturday
bringing a return of precipitation to the northern Sacramento
Valley and northern mountains, but impacts will very little and
mostly limited to the mountains in Shasta County.

//Peters

&&

.EXTENDED DISCUSSION (Sunday THROUGH Wednesday)...

An upper trough will dig into the PacNW late Sunday into Monday
bringing some chances for rain and mountain snow across the
region through middle of next week. Best chances and QPF will be
across the foothills and mountains, producing up to 0.25-0.50"
with snowfall totals of 6-12" in the Sierra Sunday into Monday.
Confidence in the exact snow levels and snow amounts is somewhat
low, but it`s noted that the current forecast does have snow
levels decreasing late Sunday into Monday, dropping down to
1,000-2,000 feet. These snow levels may allow for light
accumulations in the foothills early Monday morning as the
precipitation shifts south.

Lingering showers and mountain snow showers will be possible
Tuesday into Wednesday as the back-edge of the trough keeps
unsettled weather across the region.

Below normal temperatures expected through the extended forecast
period.

//Peters

&&

.AVIATION...

Periods of MVFR conditions to locally IFR conditions due to lower
ceilings, showers/thunderstorms. Isolated thunderstorms possible
til 03z Thursday. With any thunderstorms that develop expect
locally gusty winds, with gusts generally to 25 knots. Shower
chances will decrease this evening, with mostly dry conditions by
06-07Z Thursday. Lingering lower SCT to BKN aoa 3Kft will remain
through Thursday afternoon for portions of the central valley.

&&

.STO WATCHES/WARNINGS/ADVISORIES...
Winter Storm Warning until 7 PM PST this evening for Burney
Basin / Eastern Shasta County-West Slope Northern Sierra Nevada-
Western Plumas County/Lassen Park.

&&

$$