Area Forecast Discussion
Issued by NWS Sacramento, CA
FXUS66 KSTO 232245
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
345 PM PDT Thu Oct 23 2014
A stalled cold front will keep showers over the northern
Sacramento valley this evening. Dry and warming conditions on
Friday as a ridge of high pressure builds overhead. Saturday the
main weather system will swing into northern California and bring
more rain and cooler temperatures to the region through the
weekend. Dry weather will start the work week, but more weather
systems will move into the Pacific northwest Tuesday with Northern
California seeing clouds and some light precipitation through mid week.
A stalled cold front is resulting in a decent band of rain across
northern Sacramento valley, from Chico north, and adjacent
mountains. This front will shift north and west this evening,
shunting the showers out of the region by day break, as the main weather
system digs off the West Coast. Friday will be under high pressure
with plenty of sunshine and temperatures rebounding back to
This weekend, the main weather system will move inland and bring
widespread rain and some breezy to locally windy conditions to
the region. Saturday looks to be the day with the most activity.
Winds, widespread showers and potential for afternoon/evening
isolated thunderstorms. At this time, the winds look like they`ll
be a nuisance for outdoor events and may blow holiday decorations
around. However, the slower progression of this system may result
in slightly higher winds. We will continue to monitor later runs
and see if any wind headlines are necessary. Also, the snow levels
are expected to lower to around 7000 feet Saturday night, so there
could be some light accumulations over the higher passes. Showers
will linger on Sunday, but should see decreasing showers from
south to north through the day. Precipitation amounts this weekend
should be a couple tenths in the San Joaquin Valley to up to half
an inch in the northern Sacramento Valley. The mountains could see
1-1.5 inches of liquid.
.Extended Discussion (Monday through Thursday)
Monday will once again see a drying trend as a weak ridge builds
in behind the exiting system with temperatures rebounding to near
Tuesday through the end of the week, a series of weather systems
will flatten the ridge as they move through the Pacific Northwest.
These waves will result in an increase of clouds and cooler
temperatures with a chance of precipitation across the northern
mountains on Tuesday and Tuesday night. Beyond Tuesday night, the
models really begin to diverge so confidence in the Wednesday and
Thursday forecast is low. GFS rebuilds a fairly strong ridge over
the west coast Wednesday and Thursday, while the ECMWF and GEM
dig the next upper trough into the eastern Pacific. Therefore,
kept a slight chance of showers in the mountains and near seasonal
temperatures. We will continue to monitor the models and adjust
the forecast as needed.
A stalled cold front over northern Sacramento valley is producing a
persistent band of rain from Chico north to the Oregon border.
This rain is resulting in MVFR conditions with isolated IFR in
stronger cells. The rain will shift north and west between 02-08z
and remain along the coastal range and locations west overnight.
Ceilings will lift and shift west overnight as drier air moves
into the region. Friday will see just high thin clouds with winds
from the south between 10-15 mph in the afternoon.