1. Tornadoes
Margaret Loik & Aleksandra Ruutsaar

2. • A tornado is a violently rotating column of
air that is in contact with both the surface
of the earth and a cloud .
• They are often referred to as twisters or
cyclones.
• Tornadoes come in many shapes and sizes,
but they are typically in the form of a visible
condensation funnel, whose narrow end
touches the earth and is often encircled by
a cloud of debris and dust.
• Most tornadoes have wind speeds less than
110 miles per hour (177 km/h), are about
250 feet (76 m) across, and travel a few
miles (several kilometers) before
dissipating.
• The most extreme tornadoes can attain
wind speeds of more than 300 miles per
hour (483 km/h), stretch more than two
miles (3.2 km) across, and stay on the
ground for dozens of miles (more than 100
km).

3. Tri-State Tornado
The Great Tri-State Tornado of Wednesday,
March 18, 1925, was the deadliest tornado in
U.S. history. Inflicting 695 fatalities, the tornado
killed more than twice as many as the second
deadliest, the 1840 Great Natchez Tornado.
The continuous 352 km track left by the
tornado was the longest ever recorded in the
world: the tornado crossed from southeastern
Missouri, through southern Illinois, then into
southwestern Indiana.Snapping not only trees
and houses in its wake, this Tornado snapped
records for wind speed, length of path and
duration.
The Tri-State tornado waltzed its way through a
total of 10 cities, leaving 6 of them completely
in ruins, and severely damaging the other 4.
Massive amounts of dust and debris hid the
tornado's base and funnel and prevented
people from seeing the massive tornado
approaching

4. Great Natchez Tornado
The Great Natchez Tornado hit Natchez, Mississippi on May 7, 1840. It
is the second deadliest single tornado in United States history, killing
317 people It is also the only recorded massive tornado in the U.S.A.
that killed more people than it injured: only 109 were injured. The
Fujita scale rating of this tornado is almost certainly an F5 but since
there was no Fujita scale at the time, this tornado remains
uncategorized.
The tornado formed southwest of Natchez, shortly before 1 p.m., and
moved northeast along the Mississippi River.
The vortex then struck the river port of Natchez Landing, located below
the bluff from Natchez. The mile-wide tornado tossed 60 flatboats into
the river, drowning their crews and passengers. A piece of a steamboat
window was reportedly found 30 miles (50 km) from the river. Many
doing business onshore were also killed. At Natchez Landing, the
destruction of dwellings, stores, steamboats and flatboats was almost
complete.

5. Daulatpur-Saturia tornado
The Daulatpur-Saturia, Bangladesh Tornado was an extremely destructive tornado that
occurred in the Manikgonj District, Bangladesh on April 26, 1989. It was the costliest and
deadliest tornado in Bangladesh's history. There is great uncertainty about the death
toll, but estimates indicate that it killed around 1,300 people, which would make it the
deadliest tornado in history. The tornado affected the cities of Daulatpur and Salturia
the most, moving east through Daulatpur and eventually northeast and into Saturia.
Previously, the area that the tornado hit had been in a state of drought for six months,
possibly generating tornadic conditions. Damage was extensive over the area, as
countless trees were uprooted and every home within a six square kilometer area of the
tornado's path was completely destroyed. After the storm hit, an article in the
Bangladesh Observer stated that "The devastation was so complete, that barring some
skeletons of trees, there were no signs of standing infrastructures". The tornado was
estimated to be approximately one mile wide, and had a path that was about 50 miles
long, through the poor areas and slums of Bangladesh. Approximately 80,000 people
were left homeless by the storm, and 12,000 people were injured by the storm. Saturia
and Manikgonj were both fully destroyed by the tornado. The Fujita scale rating of this
storm is unknown due to poor housing construction and lack of data. In Bangladesh,
housing construction in the poor areas is very poor, so sometimes a strong gust of wind
may knock over a home and kill the residents inside. This is also why the vast majority of
homes hit by the tornado were leveled

6. The 2011 Joplin tornado
The 2011 Joplin tornado was a catastrophic EF5
multiple-vortex tornado that struck Joplin, Missouri in
the late afternoon of Sunday, May 22, 2011. It was part
of a larger late-May tornado outbreak sequence and
reached a maximum width of nearly 1 mile (1.6 km)
during its path through the southern part of the city.
A total of 158 people were killed by the tornado and
over 1,100 injured. It was the deadliest tornado in
America since 1947.
The insurance payout is expected to be $2.2 billion; the
highest insurance payout in Missouri history, higher
than the previous record of $2 billion in the April 10,
2001 hail storm.

7. 1999 Oklahoma tornado outbreak
The second most expensive tornado
outbreak in U.S. history and the deadliest
of the year occurred May 3–4, 1999, in
Oklahoma and Kansas. In less than 21
hours, a total of 74 tornadoes touched
down across the two states, with as many
as four tornadoes from different storms on
the ground at once.
An F-5 tornado, the strongest on the Fujita
Tornado Scale, moved along a 61-km path,
from Chickasha through south Oklahoma
City and the suburbs of Bridge Creek,
Newcastle, Moore, Midwest City, and Del
City. With 8,000 buildings damaged, the
Oklahoma City tornado is the second most
expensive single tornado in history, causing
about a 2 billion dollars in damage. In all,
the tornadoes killed 46 people, injured 800,
and caused $1.5 billion in damage.

8. The May 2007 Tornado Outbreak
• The May 2007 Tornado Outbreak was an extended
tornado outbreak that started on May
4, 2007, affecting portions of the Central United
States.
• The most destructive tornado in the outbreak
occurred on the evening of May 4 in western
Kansas, where about 95% of the city of
Greensburg in Kiowa County was destroyed by an
EF5 tornado.
• The super cell killed at least 13 people including
11 in Greensburg and two from separate
tornadoes.
• At least 60 people were injured in Greensburg
alone. It was the strongest tornado of an outbreak
which included several other tornadoes reported
across Oklahoma, Colorado, Kansas and South
Dakota that occurred on the same night. 25
tornadoes were confirmed that night.
• The outbreak did not end there; a total of 84
tornadoes were confirmed reported on May 5 in
the same area
• Damages:$268 million The center of Greensburg, Kansas, twelve days after being
hit by the 2007 tornado

10. Tornadoes are classified into 5 different categories
depending on wind speed. The 5 categories are :
Damage
Scale Km/H Miles/H Frequency
path(meters)
F0 64-116 40-72 38.9% 10-50
F1 117-180 73-112 35.6% 30-150
F2 181-253 113-157 19.4% 110-250
F3 254-322 158-206 4.9% 200-500
F4 333-418 207-260 1.1% 400-900
F5 419-512 261-318 <0.1% >900