Download Ch 17 Weather Patterns

Ch 17 Weather Patterns
Modified True/False. If false, change the identified word or phrase to make the sentence
true.
1. Cold, humid air masses that bring fog to the West Coast are continental polar air
masses.
2. At a warm front, warm air meets and moves over cold air.
3. The decreasing air pressure of anticyclones is often associated with storms and
precipitation.
4. During a tornado, a basement is the safest place to be.
5. Tornadoes form in the same kind of cloud as thunderstorms.
6. A person who is caught in a flood while inside a car should leave the car.
7. Most flash floods are caused by large amounts of melting snow.
8. Weather balloons in the exosphere carry cameras that are used to photograph clouds.
9. Rain or snow usually is associated with falling air pressure.
10. On a weather map, isobars join places that have the same air pressure.
Complete each sentence.
11. A ____________ air mass can bring thunderstorms to the United States in summer.
12. Hot, dry air moves into the Southwest in summer from a ____________ air mass.
13. A/n ____________ front may bring many days of rain because neither air mass can
move the other.
14. Where a warm air mass is caught between two cooler air masses, a/n____________
front occurs.
15. From the center of a “high” or ____________, winds spiral outward toward areas of
low pressure.
16. During a thunderstorm, a person should not touch objects that are made of
__________.
17. Before a hurricane occurs, people may be asked to ____________, or leave their
homes.
18. A large amount of humid air that cools below 0o C can produce a ___________
storm.
19. Storms that form within large cumulonimbus clouds and produce rain and lightning
are called ___________.
20. To be safe from the cold during a _____________, try to find shelter from the wind
and cover any exposed parts of the body.
21. When so much water pours into a river that it overflows its banks, a/n ___________
occurs.
22. Sudden, violent floods that occur within hours or minutes are called _____________.
23. Scientists called _______________ study the causes of weather and attempt to
predict it.
24. A long-lasting storm that begins over the warm surface of the ocean and has winds of
119km/hr or higher is a/n _____________.
25. Weather forecasters use ____________ to quickly process information from
instruments and make forecasts.
26. On a weather map, places that have the same temperature are joined with lines called
_________________.
27. A weather map uses triangles and half-circles to show the type and direction of
movement of ________________.
28. On newspaper weather maps, colors are often used to indicate ________________
ranges for different areas.
29. A/n ________________ front is a fast-mving front that often brings thunderstorms
followed by clear skies.
30. Cold, dry ____________ air masses blow into the United States from central Canada.