Transcript Chapter 11 - Cal State LA

Chapter 11 Hurricanes
 Maritime Tropical air-masses (mT) air
 Streamlines are used to analyze and track
weather
 Tropical waves
Clusters of thunderstorms
 Tropical squalls
 Easterly waves

 Hurricanes
Same as typhoons, cyclones
 Form in different parts of the world
 West of Dateline: called typhoons

Hurricanes
 Intense storm of tropical origin with sustained winds
exceeding 64 knots (74 mi/hr)
 Hurricanes, typhoons, cyclones
All form in warm tropical waters.
 They occur in the

• North equatorial Pacific
• Northwest Atlantic
Sea surface Temperatures must be in the low 80’s
 Dept of warm water needs to be at least 300 ft.
 Enough water vapor must be in the air for a tropical wave to
become a hurricane
 Winds need to be calm from surface to upper atmosphere for
hurricanes to form

Hurricane Movement
 Hurricanes develop in the low latitudes
 They are pushed by easterly winds
 As they move north, they encounter winds of
higher latitudes
Subtropical High Pressure systems to the north
 Sub polar low or low pressures systems to the north
 Hurricanes are difficult to forecast beyond about three
days
 Hurricanes tracks are getting better to forecast, but their
intensity remains an issue

Hurricanes Hazards
 Storm surge
 Hurricane
pushes ocean out ahead of storm
 Heavy rain-flooding
 Rainbands
associated with hurricanes
 Strong winds
 Associated
with storm, especially around the center
 Small tornadoes
 Around
the northeast part of the storm
 Wind shear develops as the storm moves ashore
End of Chapter 11
 Key Terms
 Questions for Review: 1, 2, 3 4, 5, 6,
7a-b, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18,
21, 22
 Questions For Thought and
Exploration: 3, 4, 6, 5