Buffalo herd spotted in Hayden Valley as storm clouds roll in Yellowstone National Park (September 17-20, 2009)

Storm clouds looming on the horizon as the Yellowstone River winds its way through Hayden Valley Yellowstone National Park (September 17-20, 2009)

My daughter spotted this rainbow over Yellowstone Lake as we were sitting in rocking chairs on the porch of Lake Lodge Yellowstone National Park (September 17-20, 2009)