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each year America gets around four times
as many twisters as the rest of the
world combined taken all together
countries outside the US see around 200
to 300 twisters annually compared to
more than 1,200 that strike American
soil so what makes the u.s. so special
to make a tornado you need just the
right mix of ingredients warm humid air
near the ground cold air higher up in
the atmosphere and wind that overlaps
while moving at different speeds or
directions
believe it or not few places on earth
check all of these boxes and none
compares to the great plains of the
United States also known as Tornado
Alley and that's largely thanks to this
the Gulf of Mexico the Gulf of Mexico is
actually the warmest body of water on
earth at its latitude and when it comes
to making tornadoes the warmer the air
the better as hot air rises off the Gulf
it crawls north across the plains where
it meets air blowing West out of the
American Rockies
and when the two come together they can
create a vortex of wind that spins
horizontally now here's where that warm
air is key as it rises as warm air likes
to do it tilts part of the tube vertical
to form a rotating storm called a
supercell and up to 20% of those super
cells spawn tornadoes now you can find
these conditions elsewhere in the world
so anywhere where you can find warm
water that's Equator word of some area
that also finds itself downwind of a
major mountain chain tornadoes have an
elevated risk I would say take
Bangladesh for example warm humid air
spreads from the Bay of Bengal and
travels north where it overlaps with
winds blowing southeast out of the
Himalayan mountains this produces an
average of around 6 tornadoes each year
including the world's deadliest which
struck in 1989
it killed 1,300 people and injured
another 1,200 more
but six tornadoes a year doesn't even
come close to the 1200 we see each year
in the US my goodness
that is a thing of beauty and tornadoes
don't just strike the US during tornado
season from March through June in
January for example we get about 36 of
them that's because you can find those
perfect tornado conditions year round
and over a region several times the size
of Bangladesh
but that said tornadoes are probably not
as common in the US as you think most
people greatly overestimate how often
tornadoes occurred in Tornado Alley
maybe if you watch the movie twister
it's easy to think that every day at 4
o'clock they sound the alarm and just go
underground that really most people who
live in Oklahoma have never seen a
tornado before that's because even in
Oklahoma
the tornado capital of the world these
storms only strike the same spot once
every 1200 to 1500 years on average
tornado winds can reach a whopping 400
km/h plenty fast enough to sweep you and
everything else off the ground
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