Tornadoes

Tornadoes are the most violent storms , according to the national Oceanic and Atmospheric Administration or NOAA . These violent storms frequent the United States east of the Rocky Mountains during the spring and summer months . It is defined as a violently rotating column of air extending from a thunderstorm to the ground (NOAA ) For it to be called a tornado , it must be in contact with the cloud and the ground base (Edwards ) It is very destructive , causing damage in excess of one mile wide and 50 miles long (NOAA

What 's so interesting

about tornadoes is that even scientists do not know how they form (Edwards ) Usually , it is started by a change in wind direction and an increase in the wind speed . This is invisible , but can be felt because it occurs in the lower part of the atmosphere . The change in the wind direction and wind speed causes a horizontal spinning effect , and combined with the rising air within the thunderstorm , this horizontal spinning wind turns vertical , usually two to six miles wide A low cloud base can then be seen , identifying the place where the tornado will come from . This place is usually rain-free , and when the low cloud base strikes the ground , we then have a tornado . Softball-size hail and straight-line winds also occur with the tornado (NOAA ) But don 't be scared ! Hail , winds and rain do not immediately mean a tornado Always be on the lookout though , because they can be indicators of an incoming tornado (Edwards

Tornadoes take many shapes , sizes , and strengths but those are not indicators of its strength . For size , tornadoes can be classified into rope , which is narrow , and wedge which is wider (Edwards ) Strength can be classified into weak tornadoes , which is 69 of all tornadoes , strong tornadoes which is 29 of all tornadoes , and violent tornadoes which is 2 of the tornadoes . The last one , even though it rarely occurs , is the most destructive , causing 70 of all tornado deaths (NOAA ) Another classification is the multivortex tornado , which contains two or more smaller rotating winds called subvortices inside a larger cyclone (Edwards

The strength of a tornado can be measured by the F-Scale , developed by Dr . T . Theodore Fujita . It relates the degree of damage to the intensity of the wind . The wind speeds of the original F-Scale was never scientifically proven , and so the Enhanced F-Scale was made . This scale was better than the first one , because it believes that a tornado scale should take into consideration the strengths and weaknesses of the different kinds of structures . No tornado is insignificant , really , but tornadoes with a F2 scale rating is considered to be a significant one (Edwards

Tornadoes can occur anytime of the year , but it is most frequent during March to May in the southern states , while it is most frequent in summer in the Northern States (NOAA

In the U .S , the National Weather Station (NWS ) issues tornado forecasts nationwide . There is no easy...