Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Sacramento California
921 am PST Sat Jan 31 2015
light precipitation possible in far northern portions late Sunday
into Wednesday. Some breezy north to east wind continues into
early afternoon with above normal temperatures. Night and morning
fog possible in the Central Valley Sunday into early next week.
Models suggest change to a potentially wet weather pattern towards
the end of next week.
Short term discussion (today through tuesday)...
strong high pressure today will bring record and near record heat
to the interior. A system will be moving into the Pacific
northwest Sunday. The tail end will skirt the far northern
sections of the state may bring a little precipitation through
Tuesday to the northern half of the Sacramento Valley and
For the Sacramento region and areas southward expect conditions to
remain dry with patches of night and morning fog through the
central part of the valley.
Extended discussion (wednesday through saturday)
Upper ridge centered along the West Coast at mid-week is forecast
to shift into The Rockies by the end of the week setting up a
period of moist southwesterly flow across the area late in the
week. Relative measure of predictability of the large-scale
features (ridge over The Rockies and trough over the Gulf of
alaska) is high, so confidence in the pattern developing toward
wet late next week is continuing to increase.
Models depict a wide swath of deep tpw (in excess of 1.5 inches)
extending into norcal late in the week with increasingly strong
forcing coming into play by Friday. At this time, appears the
heaviest quantitative precipitation forecast is still centered mainly north of I-80 by the GFS.
We'll continue to monitor trends.
Mainly VFR conditions across interior norcal next 24 hours, except
local MVFR/IFR conditions in the northern San Joaquin Valley early
North winds 10-20 kt along the northern and western Sacramento
Valley will continue through midday, then diminish. Over higher
terrain, areas NE winds 25-35 kts decreasing this afternoon.