of destructive tornadoes, building codes, such as requiring strengthened roofs and more secure connections between the building and its foundation, are not necessarily stricter compared to other areas of the United States and are markedly weaker than some hurricane prone areas, such as south Florida. One particular tornado-afflicted town, Moore, Oklahoma, managed to increase its building requirements in 2014. Other common precautionary measures include the construction of storm cellars and the installation of tornado sirens. Tornado awareness, preparedness, and media weather coverage are also high. The southeastern United States is particularly prone to violent, long track tornadoes. Much of the housing in this region is less robust compared to other areas in the United States, and many people live in mobile homes. As a result, tornado-related casualties in the southern United States are higher. Significant tornadoes occur less frequently than in the traditionally recognized tornado alley; however, very severe and expansive outbreaks occur every few years. Frequency of tornadoes These figures, reported by the National Climatic Data Center for the period between 1991 and 2010, show the seventeen U.S. states with the highest average number of tornadoes per per year. Florida: 12.3 Kansas: 11.7 Maryland: 9.9 Illinois: 9.7 Mississippi: 9.2 Iowa: 9.1 Oklahoma: 9 South Carolina: 9 Alabama: 8.6 Louisiana: 8.5 Arkansas: 7.5 Nebraska: 7.4 Missouri: 6.5 North Carolina: 6.4 Tennessee: 6.2 Indiana: 6.1 Texas: 5.9 Tornadoes in Canada Canada gets the second most tornadoes in the world after the United States. The average number of tornadoes per equal area of land is highest in the southern parts of Alberta, Saskatchewan, Manitoba, and Ontario. Roughly half of all Canadian tornadoes strike the Canadian Prairies and Northern Ontario as far east as Lake Superior. Together, these regions make up the northernmost border of the U.S. Tornado Alley. Tornadoes up to EF5 in strength have been documented in this region. Another third of Canadian tornadoes strike Southern Ontario and Quebec, especially in the region between the Great Lakes and the nation's capital city, Ottawa. Tornadoes do not often hit lake shadow regions, although they are not unknown, and some, such as the 2011 Goderich tornado, and the 2018 Ottawa tornadoes have been violent. However, most Ontario tornadoes are concentrated in a narrow corridor from Windsor to Ottawa as well as through portions of Central Quebec. Tornadoes up to F4 in strength have been documented in this region. Southwestern Ontario weather is strongly