Severe Storms…

Lesson 8

Severe Stormspgs. D74-D81

Chapter 11 Lesson 8

1. thunderstorms…• Most common kind of severe storm.• Form in clouds called thunderheads (cumulonimbus

clouds)• The lightening heats the air and causes the noise called

thunder.• Usually have heavy rains and strong winds.• Starts when intense heating causes air to rise very

quickly.

2. tornadoes…• Are a violent whirling wind that moves across the

ground in a narrow path.• Often grow out of a thunderstorm.

3. hurricanes….• Are very large, swirling storms with very low

pressure at their center.• Form over tropical oceans near the equator.• Hurricane winds whip up large waves in the

ocean.

4. storm surge…• Is a great rise of the sea along a shore.

• Causes the most destruction.

• Its main cause is low air pressure.

Discovery Education Video

Weather Smart: Tornadoes (15 min.)http://player.discoveryeducation.com/index.cfm?guidAssetId=B3C0DBEE-FB31-4DBE-94CC-F5381BE77817&blnFromSearch=1&productcode=US

Where do most tornadoes occur?(Explore Activity with Skolaut or Gupton pg. D75)

Discuss

maps of Tornado Alley on next slide…

Tornado Alley

Tornado Alley includes parts of Texas, Oklahoma, Kansas, Nebraska, eastern Colorado and western Iowa, and is characterized by a high frequency of strong and violent tornadoes and a relatively consistent season from year to year.

• The main hazard of a thunderstorm is:

A) thunder

B) funnel-shaped winds

C) heavy rain

D) lightning

• A hurricane is approaching the east coast of Florida. What dangers should the people there take precautions against?

A) cold temperatures, blowing snow, and poor visibility

B) funnel-shaped winds that can lift large objects

C) lightning and hailstones

D) flooding, large waves, and strong winds

• Why do hurricanes usually start over oceans near the equator?

A) the air is warm and moist near the equator.

B) the ocean currents are stronger near the equator.

C) The winds blow only to the west near the equator.

D) the sky usually has fewer clouds near the equator.