December 28, 2017 – Generally dry weather through the rest of the year with above normal temperatures and patchy morning fog. There is the potential for precipitation for the middle of next week.
Discussion
Little change in weather is expected over the area through the short term, as upper level ridging brings dry weather with mild high temperatures. Morning fog and cool temperatures continue, with local frost possible.
The only exception to the dry weather is for Shasta County southward to Lassen Park on Saturday, where a slight chance of showers is possible as a weakening frontal band moves into the area. Dry and mild weather is expected for the final day of 2017, with pleasant weather expected for outdoor events for New Years Eve.
Extended discussion (Monday through Thursday)
Upper level ridging will dominate across interior NorCal for the beginning of the extended period. Although models agree on trying to weaken the ridge by the middle of next week, they continue to show poor run to run consistency. An upper trough is expected to push onshore but exact timing and precipitation coverage remain uncertain, with the latest 06z GFS being faster and wetter than the previous run. For now, have introduced a chance of precipitation over the mountains Wednesday night into early Thursday, leaning towards a blend of the GFS and the ECMWF. Stay tuned for updates.