This week's covers just say "summer" to me, starting with this Spring 2016 issue of River Teeth: A Journal of Nonfiction Narrative. The cover photo is of Chipmunk Creek, Richland County, OH by David FitzSimmons.
The Gettysburg Review Autumn 2016 issue features The Letter A, detail by Alexandra Tyng, 2012, oil on linen. The publication also includes a full-color portfolio of eight of his works.
The online publication Ragazine features Castles in the Sky, oil on watercolor paper by Laura Guese, and also includes an interview with her in the issue here.