Area Forecast Discussion
Issued by NWS Sacramento, CA
FXUS66 KSTO 130613
Area Forecast Discussion
National Weather Service Sacramento CA
1015 PM PST FRI FEB 12 2016
Dry and mild weather through early next week with well above
normal temperatures. Wetter and cooler weather pattern expected
middle to latter portion of next week.
Upper trof moving through Norcal with weakening surface front. CI/CS
streaming into Interior NorCal is now sagging SEwd with upper trof.
Moisture profiles from BUFKIT show high cloudiness eroding/
dissipating around 12z at the TAF sites in the Srn Sac/Nrn SJV with
winds turning NW. This should limit/preclude widespread fog
production. Subjective analysis is the HRRR is likely hitting the )
VSBYS too hard in the Vly Sat morning...and believe the fog will not
be as dense or cover as much area as forecast. The patchy fog
wording currently in the zones should suffice. JHM
Heights and thicknesses progged to increase over the weekend as
upper ridge amplifies off the West Coast. High temperatures
forecast mainly in the lower 70s Saturday for the Central Valley,
which is upwards of 10 to 12 degrees above normal and at record
values for KSAC/KSCK. Some short lived patchy morning valley fog
will continue to be possible over the weekend from Sacramento
Another weak weather system rides over the ridge Sunday with some
light overrunning precip possible into far northern portions of
CA. However associated precip continues to be modeled north of
our forecast area. Surface high pressure building through Oregon
into the Great Basin will result in some locally breezy northerly
wind from Sunday afternoon into Monday. High temps expected to
slowly trend up over the weekend into Monday. Max Ts in the
Central Valley expected in the mid to upper 70s Sun/Mon with
readings continuing right around record values for the Sacramento
and Stockton areas.
.EXTENDED DISCUSSION (Tuesday THROUGH Friday)
Conditions will remain dry through Tuesday. On Wednesday, NorCal
transitions into a wet pattern as a trough impacts the west coast.
Both the GFS & ECMWF models agree that this storm will start
impacting our region by Wednesday evening. However, the challenge
with this system is that the models disagree on the details. The
GFS shows a quickly moving trough that weakens by Thursday
morning and puts our region back into a dry, ridging pattern by
Thursday afternoon/evening. The ECMWF indicates a stronger,
wetter trough that keeps a threat of precipitation in our CWA
through Thursday evening. Have medium confidence that interior
NorCal will get light to moderate rain/snow Wednesday evening into
Thursday afternoon with snow levels around 5000 ft.
The models continue to diverge on Friday with the GFS maintaining
a dry ridge while the ECMWF brings in another wave of
precipitation that impacts area north of Interstate 80. Confidence
is lower, but have kept lingering chances of precipitation
through Friday until models come into better agreement.
SWly flow alf vrg to NWly Sat. Vrbl clds AOA FL120 for Intr NorCal
nxt 24 hrs with VFR conds exc isold MVFR/IFR/LIFR poss in Srn
Sac/Nrn San Joaquin vlys in BR/FG btwn 10z-18z Sat.