The Pineapple Express (strong atmospheric river of very moist subtropical air) is hammering the central California coast this morning and will move inland today favoring the northern and central Colorado mountains through Sunday.
This large storm will begin in earnest late afternoon and continue through tonight with a lull Saturday morning then will kick in again Saturday night into Sunday bringing very wet sleet/snow/some rain to alpine terrain and rain below in the valleys. Very warm spring temperatures accompony this storm and until a cold front joins the equation late Saturday evening/early Sunday morning the impressive moisture plume will produce mostly rain and sleet except above 12,000′.
The San Juans unfortunately will generally receive less snow because the storm track of these two large disturbances are just north of us although we might get 8-12″ of snow if the firehose express tracks a bit south. This is a very impressive warm/wet storm for this time of year… check out more information about the Pineapple Express.
Visible Water Vapor – GOES West 12 hr Loop
GFS – US – 500mb – Loop