Area Forecast Discussion
Issued by NWS Sacramento, CA
FXUS66 KSTO 012238
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
338 PM PDT TUE SEP 1 2015
Temperatures will drop to below normal by Wednesday as another
weather system moves into the region. Most of the showers are
expected to remain across the far northern portion of the state.
Milder conditions will return for the Labor Day weekend.
Clear and sunny weather today with current temperatures near
normal levels. A change is in the works, though, as a much cooler
airmass drops down with a Gulf of Alaska trough. High
temperatures on Wednesday will be 5-8 degrees below normal levels,
then drop further on Thursday and Friday. Saturday may warm
slightly if the trough exits begins to exit more quickly (European
Model) or may stay cool (GFS Model). Sunday should see a return to
near normal temperatures, continuing for Labor Day into next Tuesday.
For this evening and into Wednesday, a strengthening Delta Breeze
will bring cooler temperatures into the Delta, southern
Sacramento Valley and northern San Joaquin Valley. The marine
layer may thicken enough to bring some low clouds through the
Delta into the Sacramento metro area, which could bring a mostly
cloudy period in the early/mid morning.
Precipitation potential appears to be limited to the northern
mountains, starting late Thursday and lingering into Saturday.
Instability aloft with cold air aloft and surface heating may be
sufficient for some Friday afternoon thunderstorms over the Burney
Basin to Lassen National Park area so have added this to the
forecast. The core of the low will likely pass a little to the north
of the forecast area, though, along with the best potential for
Some breezy northerly winds are possible for the weekend in the
wake of the trough. These could bring warming and drying
conditions, and potentially some fire weather concerns. EK
VFR mostly SKC or SCT250 conditions through 00z Thu over most of
interior Norcal. Possible stratus spreading through the Carquinez
Strait and into the Srn Sac Vly aft 12Z Wed thru 17Z Wed with
SCT-BKN010 tops 025 MSL affecting TAF sites at KSAC/KMHR. Winds
mostly up to 10 kts except for a strengthening Delta Breeze after
00z Wed with gusts 25-30kt.