Top Camping Tips - North Dakota Camping Gems - North Dakota Tips Weather With the hottest summer month, July, topping out at an average of 83.3 degrees, you'll want to pack a few snugly clothes for night time activities or cool days. January is the coldest month with average temperatures ranging from 2 degrees Fahrenheit in the northeast to 17 degrees in the southwest.  In general, you'll find warmer temperatures in the southern part of the state.