colorectal. pertaining to or of the nature of the colon and the rectum. colorectal polyp. benign or malignant; most commonly occurs at the anorectal junction in middle-aged dogs, causing diarrhea, dyschezia and rectal bleeding.
Although favorable conditions for tornadoes in the United States can occur at any time, they are most common in spring and least common in winter. Because spring is a transitional period for the climate, there are more chances of cooler air meeting with warmer air, resulting in more thunderstorms.
Tweet. Tornadoes occur around the world, most notably in the United States, South America and parts of Africa and Asia. One of the key points of activity is a section of the U.S. known as Tornado Alley, which is considered to be where tornadoes are most common. According to the United States National Weather Service, Oklahoma City, Oklahoma, has the dubious honor of having been struck by tornadoes more often than any other city in the U.S., with the count in excess of 100.