Lesson 3.2 Weather Patterns

Vocabulary high-pressure system air mass low-pressure system front

Essential Questions What are two types of pressure systems? 1 What drives weather patterns? 2 Why is it useful to understand weather patterns? 3

Warm v. Cold Explore Activity Does the temperature of water determine how it moves? Watch what happens when warm water and cold water mix in the demonstration.

Pressure Systems Pressure systems influence local and regional weather patterns.

Air Masses Air masses are large bodies of air that have uniform temperature, humidity, and pressure.

Global Influences on Local Weather Local weather is influenced by a number of global factors including ocean currents, jet streams, and global winds. These factors have an effect on daily weather conditions and weather variables.

Fronts A weather front is a boundary between two air masses.

Warm Fronts A warm front not only brings warmer temperatures, but it also causes the wind to shift directions.

Weather Map

Mini-Assessment 1. Which image shows an approaching cold front? CORRECT B D

Mini-Assessment 2. Which weather system does this diagram illustrate? high pressure A air mass B low pressure C CORRECT front D

Mini-Assessment 3. How do jet streams influence local weather? They are the cause of global winds. A They increase the temperature of surrounding areas. B They increase the rate at which water evaporates. C They push air masses around and move weather systems. D CORRECT

Mini-Assessment 4. Which air mass contains cold, humid air? continental polar A maritime tropical C continental tropical B maritime polar D CORRECT