Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Sacramento California
404 am PST Friday Nov 27 2015
mainly dry conditions into this weekend with cold morning lows.
Uncertainty in the forecast next week. The next significant
system comes ashore next Wednesday/Thursday, but the timing has
Short term discussion (today through monday)...
a low pressure area will remain over the Great Basin through
Saturday and wrap around moisture may bring some flurries or
light snow showers to areas near the crest. High pressure area to
the north that extends into Canada will continue to filter cold
air into the region through the weekend.
Surface high pressure building into the Great Basin will help to
generate breezy to locally windy conditions in the valley through
Friday with the strongest winds over the west side of the valley.
Breezy to locally windy northeast to east winds will persist into
Saturday down the Sierra with the strongest winds happening early
to mid morning.
Breezy north to northeast winds will likely remain today and
overnight. Winds will weaken across the Eastern Valley and into
the northern San Joaquin Valley later tonight, so Saturday
morning temperature may cool to near freezing in the lighter wind
area. Lighter winds Saturday night into Sunday within the valley
will help to bring areas to widespread freezing conditions to the
valley with the coldest lows dipping into the mid 20s. We have
issued a freeze watch Sunday morning 2 to 9 am for the Central
Valley. The boundary layer is dry enough that frost should not be
a significant issue this weekend. Jclapp
Extended discussion (tuesday through friday)
high pressure ridging is expected to build and should keep much
of the area dry on Tuesday. Warmer, more seasonable temperatures
than seen recently are expected, and should continue through late
next week. There is just a slight chance of some light rain over
northern Shasta County Tuesday afternoon as a system begins to
move into far northwestern California with better chances across
the northern mountains Tuesday night into Wednesday. Models are in
rough agreement over a much more substantial system arriving
Thursday, but exactly when it arrives and departs remains
uncertain. It has a strong plume of Pacific moisture to tap into,
with the potential to bring significant snow to the mountains.
This system is not as cold as seen with recent events, but it does
look like it has enough cool air to drop snow levels below Sierra
pass levels. Stay tuned to see how this system develops! Ek
VFR conditions except locally in -shsn over the Sierra crest.
Breezy northerly winds this morning in the Sacramento Valley, with
increasing gusts in the afternoon, gusting up to 25 kt, 17z-03z.
freeze watch from late Saturday night through Sunday morning for
Carquinez Strait and Delta-central Sacramento Valley-northern
Sacramento Valley-northern San Joaquin Valley-southern