A Tornado Is Born
Use a dictionary, the Internet and other resources to define each of the words. If possible,
draw a picture of the word to help others understand its meaning.
anvil cloud: The flat, wide top of a tall thunderstorm cloud, shaped like an anvil.
Atmosphere: The layer of gases surrounding the Earth.
Condense: When water vapor cools and changes into liquid droplets.
cumulus cloud: A fluffy, white cloud usually indicating fair weather.
cumulonimbus cloud: A towering cloud often associated with thunderstorms and severe
weather.
downdraft: A downward current of air, often found in storms.
front: The boundary between two different air masses.
funnel cloud: A rotating, funnel-shaped cloud extending from a storm but not touching the
ground.
mesocyclone: A rotating column of air within a supercell thunderstorm.
supercell: A powerful, rotating thunderstorm that can produce severe weather.
thunderhead: The top part of a thunderstorm cloud, often a cumulonimbus.
updraft: An upward current of warm air.
vortex: A spinning column of air or fluid.
vertical wind shear: A change in wind direction and speed at different heights.
Marisol García
May 23rd, 2023.
A Tornado Is Born
Below is a description of the way tornadoes form. Some of the words are missing. Use the
words from the first part to complete the description. Then, draw a story board in your
notebook showing the formation of a tornado.
High in the _______atmosphere_______________, cool air pushes against warm air. The
place where the two kinds of air meet is called a __________front____________. A front
can stretch over 100 miles (161 kilometers).
On warm days, the air neat the ground is much warmer than it is at higher elevations.
Warm air rises by bubbling up from the ground, just like the bubbles in a pot of boiling
water. If the air has enough moisture in it, the moisture
______consenses________________and forms ________cumulus cloud______________.
Sometimes, the rising air is trapped by a layer of cooler air above it. As the day continues,
the warm air builds up. If this pocket of warm air rises quickly, it can break through the cap
of cooler air like water shooting up from a fountain and a
_______thunderhead_______________, or _________cumulus clouds_____________
(kyu-mya-lo-NIN-buhs) cloud grows, topped by an _________anvil cloud_____________.
The thunderheads most likely to cause tornadoes are those that form along and ahead of
fronts.
Strong, fast winds tend to blow along and above fronts. If slower surface winds blow
opposite to the direction of the higher winds, a ________vortex______________ forms.
Vertical wind shear can cause the rising air in a thunderhead to begin to rotate.
A __________supercell____________ is a thunderstorm with a constantly rotating
__________updraft____________. Supercells are responsible for a high percentage of
severe weather events, especially ___________tornadoes___________.
If the rising column of air I n a thunderhead begins to rotate, it is called a
__________mesocyclone____________ (mez-uh-Sy-klon). In a mesocyclone the updrafts
Marisol García
May 23rd, 2023.
A Tornado Is Born
and __________downdrafts ____________ are in near balance, allowing the storm to
continue for several hours.
As a mesocyclone rotates, it stretches toward warm air near the ground. The lower part of
the mesocyclone narrows. The narrower it becomes, the faster it spins.
When this ___________vortex___________ dips down from the mesocyclone, it draws in
warm, moist air. The air cools as it is pulled up into the column. Tiny droplets of water form
and a whirling cloud appears. This cloud is called a __________funnel
cloud____________.
Some funnel clouds hang straight down from the storm cloud. Others stretch side-ways
thorough the sky. A funnel cloud may dip down and retract into the mesocyclone, or it
may touch the ground. If it touches the ground, the funnel cloud is called a
____________tornado__________.
You need to bring (by table) for Thursday:
2 two-liter soda bottles with caps
2 ballons
Marisol García
May 23rd, 2023.
A Tornado Is Born
Food coloring
Marisol García
May 23rd, 2023.
