Download Severe Weather PPT - Effingham County Schools

Severe Weather
• Thunderstorms and tornadoes occur
because of sudden changes in air
pressure or as a fast moving cold
front hits a slow moving warm front.
• Large thunderstorms and tornadoes
occur most frequently in the spring
and summer. The ground is warming
and warm air masses move north
from Mexico, while cold air masses
move south from Canada.
Tornadoes are a destructive vortex of
violently rotating winds having the
appearance of a funnel-shaped cloud
and advancing beneath a large storm
system.
• A severe storm that forms as a
rapidly rotating funnel cloud is called
a tornado.
• A hurricane is a large tropical storm
system with high-powered circular
winds.
• Lightning is as hot as the surface of
the sun.
• When clouds collide they either lose
or gain electrons. This difference in
electrons causes an electron
imbalance. When the electrons flow
together to balance the electron
inequality, lightning occurs.
• Hail is formed by a
rising current of
warm air forces
water drops to rise.
When the water
droplets reach
colder, higher
altitude they
freeze. The frozen
rain droplets fall to
the ground as hail.
• Hurricanes are the largest of storm
systems.
• The storm surge of a hurricane
causes the most deaths during the
storm.
• Tornadoes have the highest wind
speed of all storms systems.
• Events, such as volcanic eruptions
and clear cutting of trees in the
rainforest, can have global effects on
weather patterns.