The weather will be fantastic for your New Years Eve celebrations! Take the jacket off in the afternoon as highs get near the mid-60s for some in the Valley, with low-60s for the rest. Mostly sunny skies will prevail in the afternoon with increasing clouds after sunset. At the stroke of midnight the new decade will start with temperatures in the mid-40s with partly cloudy to mostly cloudy skies.
New Years Day will see partly cloudy skies with cooler temperatures. Highs in the upper 50s to lower 60s. The reason for the decrease in temperatures is due to the passage of a winter system to our North. This will mainly affect the Pacific Northwest. The rain will clip our Northern counties with some showers but the rain will unlikely reach the Valley.
On Thursday we warm by a few degrees with more sunshine and Friday looks to be a rinse and repeat of Thursday.
On Saturday the next system moves in the region bringing light scattered showers in the Valley and mountians with snow levels 5,000 to 6,000 feet. The chance for rain is brief, as sunshine retuns for the rest of the weekend and at the start of next week. The brief system does lower high tmperatures, however, into the mid-50s. It also brings the chance for overnight lows to dip back into the upper-30s for a night or two.