Name ___________________________
Period _________
Storms and Severe Weather
Mid-Latitude or Cyclonic Storms
*Most of our weather in Buffalo comes from
these mid-latitude lows. These storms track
to the east or northeast because they are in
the prevailing westerlies. The faster cold
front eventually overtakes the warm front,
creating an occluded front.
1. Movements of ________ masses along the __________________ of
the middle latitudes can result in the formation of _______-pressure
storm systems called ____________________ , or just wave cyclones.
2. The __________________ is the boundary between the northerly cool
air masses in the _________________________ and the southerly
warm air masses in the __________________________.
3. The polar ______________________ is a fairly narrow zone of very
strong winds in the upper __________________ just above the polar
front (page 14 of your reference tables).
4. A “kink”, or ____________, in the polar front causes a low (L) pressure
area to develop.
5. With the help of the coriolis effect and global wind directions, cold air
(L) drives south forming a ________________, and warm
air east of the (L) drives north forming a _______________.
west of the
Hurricanes
*Hurricanes usually occur in
the late summer and early fall.
The central clear area of
sinking air is the eye, and the
intense thunderstorms
surrounding the eye is called
the eye wall. Hurricanes are
made up of spiral bands of
cumulus and cumulonimbus
clouds, which average over
600 kilometers across.
1. Hurricanes, also known as tropical ____________ or typhoons, are
intense tropical _______-pressure areas with sustained winds of
_______ kilometers per hour (74 miles per hour).
2. These low-pressure centers gain their energy from the
_____________________ of millions of gallons of water vapor. As the
tropical low-pressure center gains energy, the wind speeds
__________________.
3. Hurricanes can last for many _____________, which is why they are our
most destructive storms.
4. Although damage is caused by high winds, the greatest destruction
(widespread flooding and the collapse of buildings) is caused by a rise in
the sea called a __________________. These form when the hurricane
piles up water along the shore and then blows it inland.
Hurricane Stages & Categories
1. Tropical Cyclone – A large low
pressure system develops in the
tropics. As they strengthen…
2. Tropical Disturbance – Storm
activity between 100 to 300 miles
in size and lasting for 24 hours.
3. Tropical Depression – A tropical
cylcone with 28 to 38 mph winds.
4. Tropical Storm – Winds are 39 to
74 mph. Storm gets named.
5. Hurricane –
a. Category I - Winds 75-95 mph
b. Cat. II – Winds 96-110 mph
c. Cat III – Winds 111-132 mph
d. Cat IV – Winds 133-155 mph
e. Cat V – Winds above 155 mph
5. Atlantic hurricanes move
_____________ due to the NE
tradewinds, and sometimes hit
the U.S. coast. They then lose
strength due to the ________
of their water vapor source.
6. They usually move _______
into the prevailing westerlies,
and miss the U.S. coast.
7. Hurricane Watch – Hurricane
conditions are possible within
_______________ hours.
8. Hurricane Warning – Hurricane
conditions are expected within
________ hours or less.
Tornadoes
1. A tornado is a narrow, funnel-shaped column of spiral winds that extends
downward from the base of a ________________ cloud and touches the
ground. Tornadoes are usually only about _______ feet across, but can
get up to one mile across.
2. Tornadoes are the most violent of all storms, yet only last a few
______________. Some have lasted over an hour.
3. Tornadoes are ranked from F-0 to F-5 on the Fujita scale of tornado
intensity.
a. F-0 (gale tornado): Winds 40-72 mph; breaks branches off trees
b. F-1 (moderate tornado): Winds 73-112 mph; peels surface off roofs
c. F-2 (significant tornado): Winds 113-157; roofs torn off houses
d. F-3 (severe tornado): Winds 158-206 mph; uproots trees
e. F-4 (devastating tornado): Winds 207-260 mph; houses leveled
f. F-5 (incredible tornado): Winds 261-318 mph; cars thrown 100 meters
4. The greatest danger to humans from tornadoes is from the
________________ debris cause by the tremendous wind speeds and
the very low air pressure, which _________________ up materials from
the surface.
5. At the first warning or sighting of a tornado, go into the ____________
available structure, in the strongest ____________________, at the
___________ possible level, and _____________ your head and body.
6. Tornadoes over water are called ___________________, and are
weaker than tornadoes.
7. Below shows that tornadoes are most common in the central U.S. due to
the battle of the cold Canadian and warm tropical ________________.
Draw a Tornado
Thunderstorms
1. At any one time over ___________ thunderstorms are happening on
Earth.
2. Thunderstorms are heavy rainstorms accompanied by ____________
and _______________ from cumulonimbus clouds.
3. Thunderstorms form from the ____________ of warm moist air by cold
fronts, by convective rising from local heating, or by hurricanes.
4. Hazards of a thunderstorm:
a. ____________________
e. __________________
b. ____________________
c. ____________________
d. ____________________
5. In many years, more people get killed from ________________ than
from any other weather-related cause.
6. To protect yourself from lightning:
a. Don’t be the ____________ object in the area.
b. Don’t stand under a __________, since lightning might strike it.
c. Don’t touch ______________ devices during a thunderstorm.
d. Don’t take a _______________ or run the water from the sink.
Blizzards
1. A blizzard is a storm with winds of ________ mph or greater with large
amounts of falling/blowing snow.
2. Blizzards are usually associated with the frontal conditions of
___________________ lows.
3. Blizzards can shut down all types of _____________________, disrupt
_______________ and ________________ service, prevent people
from obtaining needed services and products such as __________ and
____________.
4. People caught in a blizzard without proper shelter and clothing can suffer
____________, _______________, and ______________________.
5. To prepare for a blizzard, people should have ___________ and other
supplies and stay indoors.
6. As a wintertime low-pressure center travels from the southwest end of
Lake Erie to the northeast end, a tidal effect occurs causing the lake
level to cycle. This tidal effect is called a ______________, and causes
major beach erosion and property damage.