Description You're welcome Nebraska! These super thunderstorm cells come flying over the Colorado Rocky Mountains and head out east to the plains. A normal spring summer day on the Rocky Mountains foothills is waking up to clear blue skies over the mountains. By 1:00 pm the clouds start rolling in and building over the foothills sometimes by 3:00 to 4:00 it rains and clears by sunset and the best is when it kicks up at sunset and last till about 11:00pm. Those are the storms best to photograph.