000
FXUS66 KSTO 022059
AFDSTO

Area Forecast Discussion
National Weather Service Sacramento CA
159 PM PDT Mon Oct 2 2023


.Synopsis...
Dry and warming conditions this week. Occaisional breezy north
wind.

&&

.Discussion...
The trough currently over NorCal continues to move eastward and out
of the area, bringing breezy northerly winds to the Sacramento
Valley as it goes. Gusts up to 25 mph will occur in parts of the
northern and western Sacramento Valley until 00z Tuesday.
Satellite images show signs of the low moving out as well, with
some clouds still lingering over the Sierra and some high clouds
over the entire area.

As the ridge to the west begins to expand over the Pacific
Northwest and heights over NorCal begin to rise, temperatures
will continue to increase through the week. Conditions will be
dry and warm, and valley highs will top out in the high 80s to low
90s towards the end of the week. The ridge will also bring
northerly to easterly winds that will pick up in speed starting
Tuesday night and into Wednesday. Humidity will lower during this
time frame as well; however with values primarily in the lower
20s to lower 30s, decent overnight recovery, and given the recent
rains, critical fire weather is not currently expected. //SP

&&
.EXTENDED DISCUSSION (Friday THROUGH Monday)...
The Eastern Pacific ridge is forecasted to progress north of
California Friday and continue to move east into the weekend. High
temperatures will continue to rise, with the NBM giving NorCal a
good chance (30-90%) of exceeding 90F Friday and Saturday. Highest
probabilities of exceeding 90F will be near the Delta, Sac Metro,
and Redding area. Isolated areas of Moderate HeatRisk in the
Delta and Sacramento area, with widespread Minor HeatRisk for most
of our area on Friday and Saturday. Behind the ridge, a shortwave
trough will encroach on our area. Ensemble guidance and the NBM
are depicting precipitation chances in northern Sac Valley Monday
afternoon. NBM currently has a non- zero chance (10-20%) for much
of our forecast area, with higher chances (30-50%) farther north
in the Coastal Range. As the trough moves through our area,
temperatures will fall again into the upper 70s for the Valley and
60s for higher elevations. Still some disagreement within
ensembles and clusters on progression of the shortwave trough, so
evolution of this system will be monitored and the forecast
adjusted as we move through the week.

Wood

&&
.AVIATION...
VFR conditions are expected over interior NorCal next 24 hours.
Surface winds generally below 12 kts. &&

.STO WATCHES/WARNINGS/ADVISORIES...
None.
&&

$$