A wedge tornado is a tornado that is at least as wide as it is tall. Some criteria that would qualify a wedge tornado includes moisture in air, intervening terrain, soil and dust lofting, cloud base height and actual tornado size. Wedge tornadoes are also associated with causing damage, producing potential F4-F5 tornadoes and covering more ground, according to National Oceanic and Atmospheric Administration.
According to AccuWeather Expert Senior Meteorologist Dan Kottlowski, a wedge tornado is a large tornado that has more than one vortice. This can be thought of as a massive cloud that produces a tornado but has many other smaller tornadoes around the center of the massive cloud.
This type of tornado forms when warm, humid air, usually from the Gulf of Mexico, collides with cold, dry air from Canada, according to Kottlowski.
Wedge tornadoes are usually more threatening than a single tornado because of their large size. They also tend to last longer, according to Kottlowski.
Kottlowski said there are usually a dozen wedge tornadoes per season and that wedge tornadoes usually develop in the Plains region during the months of April, May and June.
Southern Mississippi saw a wedge tornado earlier in February. The University of Southern Mississippi received minimal damage. There were no fatalities reported, but some people were treated for minor injuries.
A deadly wedge tornado wiped through Xenia, Ohio, on April 3, 1974, according to NOAA. This particular wedge tornado was rated a F5. More than 30 people were killed and 1,100 were injured.
Tornado safety should be practiced in preparation for severe weather. NOAA recommends practicing a weather drill at least once a year in your home, keeping an eye to the sky because tornadoes can form without warning and keeping up to date with any watches or warnings for your local area by tuning into your local weather station.
Photo courtesy of AP Images: (AP Photo/Chuck Cook) A couple cross West Arlington Loop in Hattiesburg, Miss., Monday, Feb. 11, 2013, after a tornado damaged the area Sunday afternoon.
Rain will return across much of the eastern U.S. to begin the last month of 2015.
Snow will linger across parts of the northern Plains to the Upper Midwest as December begins.
After the brief shot of chilly air this past weekend, the month of December will start out mild across the Northeast.
December will begin with a roar across the Northwest as rounds of rain, mountain snow and even ice are in store this week.
The reprieve from heavy rain across southern India will not last with the threat for flooding downpours set to return for the final day of November.
Tens of thousands will gather in rainy and mild conditions at 30 Rockefeller Plaza in New York City on Wednesday, Dec. 2, 2015, for the 83rd annual Christmas tree lighting.
Ohio, Ontario (1996)
A line of severe thunder storms moved across the state. In Cleveland, OH there was a 60 mph wind gust. An 18-foot tractor trailer was blown over on I-77 in Richfield, OH. In Guelph, ON a wind gust lifted the roof of a gym, where a church group was playing basketball. Residents of one neighborhood saw a car spinning on its grill like a top.
Erie Canal (1831)
Coldest December ever closed Erie Canal.
Snow fell for 5 minutes in South Florida in the Ft. Myers area.