Area Forecast Discussion
Issued by NWS Sacramento, CA
FXUS66 KSTO 260354
Area Forecast Discussion
National Weather Service Sacramento CA
854 PM PDT Tue Apr 25 2017
Weak weather system will bring light precipitation through
Wednesday. Dry with gusty north winds developing late in the
A weak disturbance will begin to move into the interior late
tonight and Wednesday morning. Light amounts of precipitation is
expected within the valley and over the mountains. Snow levels
will be high above 8000 feet so snow will be a non factor for
Not much change in high temperatures for Wednesday but Thursday
will warm back to near seasonal normals. Breezy north winds are
likely to develop on Thursday as high pressure starts to build
into the region. The winds still look stronger for Friday but
below advisory level with the strongest still looking like they
would occur over the San Joaquin Valley.
Dry weather persists across most of interior Northern California
as a shortwave ridge nudges into the region. A few showers are
moving through the far northern portions of the state as warm
advection starts to take hold. Under partly cloudy skies, Central
Valley locations have warmed into the upper 60s to lower 70s, with
40s to 60s over the mountains.
A series of weak weather systems will pass through the region
tonight through Wednesday. Only light precipitation totals are
expected with these systems and should occur mainly over the
mountains. The timeframe of most widespread precipitation should
occur during the day Wednesday.
After these systems pass by, a longwave trough will deepen over
the Great Basin in an "inside slider" pattern. This is
traditionally a favorable pattern for breezy north winds across
Northern California. At this stage it looks like wind gusts in
the range of 30-40 mph will be possible Thursday through Friday in
the Valley...strongest in the San Joaquin Valley.
.EXTENDED DISCUSSION (Saturday THROUGH Tuesday)
High amplitude upper ridging in the EPAC extends over Interior
NorCal through the weekend resulting in dry conditions with above
normal temperatures. Breezy northerly winds from Friday continue
into Saturday. Ridging weakens over northern portions of CA Monday
as a short wave trough digs through the PACNW into the Great
Basin. This will result in minor cooling over northern portions of
the forecast area. High pressure rebuilds behind the wave Monday
night into Tuesday resulting in a return of breezy northerly wind.
Low level CAA with this flow will offset downslope warming and
maintain slightly cooler temps of northern portions Tuesday.
North winds to 25 mph over the San Joaquin valley into the
evening...then generally light winds through Wednesday morning.
Scattered light showers over the northern Sacramento valley after