Admitted to the Union in the year 1907, Oklahoma is the 46th state of the United States. It is home to roughly 3,963,516 people, and ranks as the 20th largest state, occupying an area of 181,038 km2. Oklahoma lies midway between the humid subtropical southeast and east, the humid continental north, and the semi-arid in the west. This effectively puts it in a place where it uniformly enjoys a humid subtropical climate. This is further influenced by the moisture brought along by the winds of the Gulf of Mexico. Oklahoma faces an average of 60-65 tornadoes per year - among some of the highest numbers in the world. Precipitation levels are average, and there's most in the west than in the east.
For Oklahoma residents, rooftops have to be able to handle the extreme cold temperatures and heavy snowfall - this is a must. Shingles are by far the top choice here - but the materials vary by preferences on upkeep, maintenance, cost and aesthetic appeal. Asphalt, wood (mostly cedar), tile, metal (either seamless or corrugated and either plain or painted), rubber, metal and slate are common choices. Synthetic materials which use recycled fiber and plastic have also become recently common due to its low-cost, especially in commercial structures. Clay roof tiles, though are not popular as they do not fare well in the cold weather, and tend to become brittle fairly fast.