000
FXUS66 KSTO 291929
AFDSTO

Area Forecast Discussion
National Weather Service Sacramento CA
1229 PM PDT Mon Apr 29 2024

.Synopsis...
Mild and dry weather this week. Occasionally breezy. Light precipitation
chances return this weekend.

&&

Dry and mild weather will persist through the week as several
short-wave troughs pass to the north over broad ridging covering
the eastern Pacific and NorCal. Precipitation chances will remain
well to the north of the region across the PacNW, though
occasional bouts of north to east wind are expected as surface
pressure gradient tightens in the wake of each of these waves. The
strongest period of northerly winds are expected Tuesday night and
Wednesday with gusts of 35-45 mph possible in the Sacramento
Valley and surrounding terrain with the strongest winds forecast
to occur to the northwest of Sacramento along the west side of
the valley (NBM probabilities are around 60-80 percent for
reaching that range for wind gusts). Difficult driving conditions
can be expected and loose objects may blow around. Valley high
temperatures will be in the mid 70s to lower 80s.

&&

.EXTENDED DISCUSSION (Friday THROUGH Monday)...
Some disagreement remains with respect to the exact evolution of
a passing upper level trough, but ensembles are coming into
agreement on a shift to cooler and wetter weather next weekend
into the following week. Prior to this though, mild and dry
weather looks to hold on through Friday as a leading shortwave
ridge ahead of the trough briefly centers over interior NorCal.
This will likely result in the warmest high temperatures of the
week, with low to mid 80s in the Valley and 60s to 70s across the
higher terrain.

As the aforementioned trough moves through or in proximity to
interior NorCal, a period of more active weather will be possible
next weekend into the following week. Current cluster analysis
indicates a 40% chance of a deeper trough on a further southward
trajectory moving through NorCal and a 60% chance of a weaker trough
on a more northerly trajectory through the Pacific Northwest. That
being said, there has been a trend within latest ensemble guidance
toward the former scenario in the trough evolution. The former
scenario would provide more weather impacts of increasing
precipitation chances, breezy to gusty winds, and possible high
elevation mountain snow, with the latter scenario providing more
limited impacts of showery activity primarily confined to the
northern Sacramento Valley and adjacent terrain. As a result, there
is a fairly broad range of appreciable weather impacts at this
time. Regardless of the exact track though, a cooling trend
toward near to slightly below normal temperatures is anticipated
through the weekend into early next week.

&&

.AVIATION...
Clear skies and VFR conditions expected across interior NorCal
over the next 24 hours. Northwest winds in the Valley with
sustained surface winds 10-15 kts with gusts 20-25 kts through 00Z
Tuesday. Over the mountains, wind gusts up to 30 kts through 02Z
Tuesday. Surface winds decrease to below 12 kts (00Z to 12Z
Tuesday) before northerly winds increase to 10-15 kts with gusts
20-25 kts after 14Z Tuesday.

&&

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

&&

$$