There are many seats under cover at Coors Field. The best option is on the 200 level in right field in Sections 201-209. The majority of these rows are covered as long as you do not sit in the first three rows or so. There is also cover in the back few rows of Sections 134-148 and 118-127 because of the overhanging 200 level. The back portion of the top level of seating is also covered because there is a small overhanging roof to the stadium that will provide protection for fans sitting all the way in the back.

Cover in right field on the 200 Level at Coors Field is shown above (CreativeCommons)