March 9, 2017 – Dry and milder weather through the weekend with rain chances limited to the northern mountains through the middle of next week. Rain chances spreading southward to around Interstate 80 by the end of next week.
Discussion
Flat high pressure ridge over the west coast bringing dry conditions to the forecast area this morning with temperatures just a bit warmer than 24 hours ago. Ridge not of high enough amplitude to keep high cloud cover from spilling over the far north end of the state and can not rule out a slight threat of light precipitation over the northern mountains of Shasta county today. Otherwise, a generally fair day in store with airmass warming bringing up temperatures on the order of about 5 degrees over Wednesday with highs reaching around 10 degrees above normal.
A shortwave trough moving over the ridge and through the Pacific northwest tonight with bring a continued threat of light precipitation over the northern Shasta county mountains through the Friday morning hours. Upper west coast ridge continues to amplify on Friday with good agreement between models lifting any precipitation threat out of the region. Daytime highs continue to warm reaching the mid 70s over the northern Sacramento valley where light north winds and adiabatic warming will help boost daytime temperatures a few degrees. Persistent upper ridging keeps the forecast area under fair skies through the weekend with daytime highs continuing to warm. Redding could see 80 degrees for the first time this year.
Extended discussion (Monday through Thursday)
Mild and dry weather expected to continue into Monday, with moist flow deflected well to the north by upper level ridging. High temperatures in the mid to upper 70s across the Valley are forecast. Tuesday is expected to be slightly cooler and cloudier. A weak system passing by to the north could bring just a slight chance of light precipitation, mainly to Shasta County. This may linger into Wednesday. There is the potential for a more substantial system with a fairly strong moisture plume Thursday/Friday. This should also bring cooler, more average temperatures.