1. Predicting the Weather

2. Weather Forecasting A weather forecast is a prediction of the weather.
You use weather forecasts to decide what to wear each day and what activities you can participate in.
Scientists use tools to measure the current weather to help make their predictions about future weather.

3. Weather Maps
Weather maps can show what the weather was like in a place on a certain day.
Scientists use data from weather stations all over the world to create weather maps.

4. Weather Maps and Symbols
Click the link below to see an explanation of weather maps:

5. Air Masses There are 4 basic types:
Weather maps show the movement of air masses. An air mass is a large body of air with about the same temperature and humidity throughout.
There are 4 basic types:
Cold and Dry Warm and Dry
Cold and Humid Warm and Humid

6. Fronts
Weather Maps also show fronts. A front is a place where 2 different air masses meet.
Click below to learn more about air masses and fronts:

7. Cold Front Warm Front Stationary Front Occluded Front
Cold air mass bumps against warm air mass
Strong storms happen here (thunderstorms in warm weather, snowstorms in winter)
Causes temperature in an area to drop.
Warm air mass meets colder air mass and rises over it
Stratus clouds form which often bring rain
Causes temperature in an area to rise
Forms when 2 air masses meet and stop moving
Bring clouds and precipitation lasting longer because air masses are not moving
An occluded front is a combination of two fronts that form when a cold front catches up and overtakes a warm front.

8. Air Pressure Air pressure is measured with a barometer.
Low air pressure usually brings rainy or stormy weather.
High air pressure usually brings fair weather.

9. Weather Patterns in the United States
In the United States, weather usually moves from WEST to EAST.
Rain forming over the Pacific Ocean moves east over California and weather forming over the middle of the U.S. often moves towards North Carolina and other eastern states within days.
WEST to EAST