Weather

1
Weather Climate

• Storms

2
Objectives

• List and describe the main types of storms and
  explain how they form
• CC STATEMENT (CC 2.1.7) Global patterns of
  atmospheric movement influence local weather.

3
STORMS

• A storm is a violent disturbance in the
  atmosphere.
• They involve sudden changes in air pressure.
• Changes in air pressure causes rapid air movement.

4
Thunderstorms
Formation W/in large cumulonimbus, or thunderheads Form when warm air is forced upward at a cold front Temperature Hot, humid afternoons in the spring and summer Precipitation Heavy rainfall Sometimes hail Safety Avoid touching metal objects Install metal lightening rods Find a low area away from trees Stay away from water
5
Thunderstorms

• During a thunderstorm, positive and negative
  electrical charges build up in the clouds.
• The discharge of the electricity between clouds
  is lightening.
• Lightening is as hot as 30,000C, hotter than the
  sun.
• The heated air expands and explodes producing
  thunder.

6
Checkpoint

• What is El Nino?
• What is a storm?

• Weather pattern related to the temperature of the
  water in the tropical Pacific Ocean.
• Any type of violent disturbance in the atmosphere.

7
Tornado

• Rapidly whirling, funneled-shaped cloud that
  reaches down from a storm cloud to touch Es
  surface
• Most frightening disruptive storm
• Usually brief, touching the ground approx. 15
  minutes or less
• Wind speeds may reach 480 km/hr

8
Tornado
Formation Develop in low, heavy cumulonimbus clouds When warm dry air mass and cool air mass collide Temperature Warm humid air Spring and early summer when ground is warm Precipitation Heavy rain and wind Safety Listen for watches warnings Basement level, or to the middle room on ground floor Stay away from windows Lie in a ditch
9
Tornado

• Tornado Watch tornadoes are possibly in your
  area
• Tornado Warning tornadoes have been seen in the
  sky or on weather radar
• Occur most often in the US
• Approx. 800 tornadoes a year

10
Checkpoint

• Where do tornadoes form?
• Why is there a tornado valley?
• What states make up tornado valley?

• Low heavy cumulonimbus clouds
• Warm humid air mass moves north from Gulf of
  Mexico and meets a cold dry mass that is moving
  south from Canada
• SD, Iowa, Nebraska, Kansas, Missouri, Oklahoma,
  TX, NM, and Arkansas

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Hurricanes

• Tropical storm that has winds of 119 km/hr
• Usually occur between June and November in the
  eastern US
• Hurricanes that occur in western US are called
  typhoons
• Bring much needed rainfall to S Asia SE Asia

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Hurricanes
Formation Begins over warm water as a low pressure area, tropical disturbance Gets it energy from warm humid air at the oceans surface Temperature Warm temperatures Precipitation Strong winds Rain which generally causes flooding Safety Evacuate Move into the interior room and stay away from windows
13
Hurricanes

• Occur between June and November
• Effect people that live on the coast of the
  Atlantic, Pacific, and Indian Oceans
• Hurricanes bring needed rainfall to S Asia and SE
  Asia
• Eye center of a hurricane

14
Winter Storms

• Lake-effect Snow In the fall and winter, land
  cools faster than the lakes.
• When cool air mass moves from Canada across Great
  Lakes it picks up water vapor and heat from
  lakes.
• After the air mass
• passes the lakes it begins
• to cool and the water vapor
• condenses and falls as snow

15
HOMEWORK

• Section Review p. 91 1-4 COMPLETE SENTENCES
• Be able to explain the CC statement that relates
  to todays lesson
• BRING WORKBOOKS TO CLASS TOMORROW