Weather Unit Test

Which system results in rainy or stormy weather?

• high pressure

• low pressure

• hurricane

• weather system

Why do clouds and rain usually occur along the front?

• The warm air rises, expands, and cools.

• The warm air sinks, expands, and warms.

• The cool air rises, compresses, and cools.

• The cool air sinks, compresses, and warms.

An air mass entering Alaska from the northern Pacific Ocean would most likely be labeled on a weather map as

• cP

• cT

• mP

• mT

Which weather variable would most likely decrease ahead of an approaching storm system?

• wind speed

• air pressure

• cloud cover

• relative humidity

The map of North America below shows the source region of an air mass forming mostly over Mexico. This air mass originating over Mexico is classified as

• continental polar

• continental tropical

• maritime polar

• maritime tropical

Which atmospheric conditions occur when the dry-bulb temperature is 30°C and the difference between the dry-bulb temperature and wet-bulb temperature is 1°C?

• warm and humid

• warm and dry

• cool and humid

• cool and dry

The weather map below shows a storm centered north of Iceland. Points A, B, C, and D indicate locations on Earth's surface. Isobars are labeled in millibars. Which location was probably experiencing the highest wind speed?

• A

• B

• C

• D

The heavy monsoon rains affecting India and Southeast Asia occur during

• winter, when winds blow from the land

• winter, when winds blow toward the high pressure

• summer, when winds blow from the ocean

• summer, when winds blow toward the high pressure

Air masses are identified on the basis of temperature and

• type of precipitation

• wind velocity

• moisture content

• atmospheric transparency

Clouds usually form when

• air temperature reaches the dewpoint

• evaporation has warmed the surrounding air

• relative humidity is 0%

• condensation nuclei have been removed from the air