document: One of nature 's most vicious spectacles , the tornado , is poised to renew its annual assault on America , as changeable spring weather breeds the storms that spawn twisters . Last year was one of fewer than normal tornado deaths , but even so , more than 700 of the violent funnel clouds struck the nation . In 1988 the nation recorded 32 tornado deaths , down from the 59 killed a year earlier and well below the long-term average of 99 fatalities annually , the National Weather Service reported on Sunday . But while that 's good news , it is n't an indication that the danger has lessened . `` There is no way of knowing what this tornado season will bring , but the way to survive is through preparedness , '' said Ed Ferguson , deputy director of the National Severe Storms Forecast Center in Kansas City . Meteorologists have attributed the decline in tornado deaths in recent years to increased public awareness of the storms , which are most common in May and June but can occur in any month of the year . Unusually warm and wet weather last November helped trigger a record number of tornadoes for that month , at 121 across the country . The average for November is only 23 tornadoes , and the record had been 81 , set in 1973 . Last year also recorded the largest tornado outbreak in 14 years . That took place on Mother 's Day when 57 twisters tore through parts of Arkansas , Illinois , Iowa and Wisconsin . That outbreak did n't cause any deaths , although 10 injuries were reported . Arkansas and Tennessee recorded the most fatalities last year with six deaths apiece , followed by Florida with five . Four people were killed in North Carolina and two each in Mississippi and Nebraska . States with a single fatality apiece were Kentucky , Michigan , Missouri , New York , Oklahoma , South Carolina and Texas . The transition from winter to spring , spurring unsettled weather and frequent thunderstorms , helps create tornadoes , violently twisting winds that reach down from thunderclouds . After a low point in the winter they begin to increase sharply in March and peak in May with a national average of 166 twisters in that month , according to records kept at the National Climatic Data Center . June ranks second , averaging 150 tornadoes , followed by April with 109 in a typical year . Other months averaging more than a twister-a-day somewhere in the nation are July , 82 ; August , 57 ; March , 50 and September , 38 . Hot weather stirring the air helps form thunderstorms and their tornadoes , with 60 percent of all twisters occurring between noon and sunset , according to the National Center for Atmospheric Research . Tornadoes are least likely during the early morning just before sunrise . The typical tornado is only about 50 yards wide and travels about two miles on the ground _ 87 percent of the time heading toward the northeast , NCAR researchers report . But while an individual twister can cover only a small area , they often come in groups and in the affected area destruction can be total . The familiar funnel cloud is the most common sign of a tornado although adjacent winds can also cause severe damage . When twisters are in an area , common sense and knowing a few simple rules can save lives , the National Weather Service says . If tornadoes threaten , turn on radio or television to keep current on the danger , the agency says . The weather service even has its own radio network which can provide continual updates . If a twister is reported , safety rules include : _ At home , seek shelter immediately in a basement or interior hallway . Stay away from windows and outside walls . _ At school , move to hallways and lie flat on the floor with head covered . _ In a mobile home or trailer , leave immediately . Head for a secure shelter or lie flat on the ground . Be wary of areas with poor drainage , however , because of the possibility of flooding from the thunderstorm . _ At work or in public buildings , head for interior hallways on the lowest floor , or designated shelter areas . _ In an automobile , leave immediately . Do not try to outrun a tornado .
extractive_keyphrases: tornadoes tornado deaths tornado outbreak public awareness storms tornado season fatality