2Review 13: Weather Meteorologist – scientists who study the weather. What direction do most weather systems travel in the U.S.?
3How many types of precipitation can you name? Review 13: Weather2. Humidity – the amount of water vapor in the air. Determines whether precipitation will fallThe higher the humidity, the more likely it is there will be precipitation.3. Water cycle – drives the Earth’s weatherHow many types of precipitation can you name?condensationcondensationprecipitationtranspirationevaporationrunoffground waterwater
4Review 13: Weather3. Air pressure – the weight of all the air molecules in an area.4. Barometric pressure – air pressure caused by the weight of the air.
5Review 13: Weather5. High-pressure system – when cold air sinks to the ground, warms up, and absorbs water vapor, causing sunny skies.6. Low-pressure system – when warm air rises higher in the sky, causing water vapor to cool and form clouds and precipitation.Predict what will happen if a high-humidity air mass located over an ocean moves inland and up a mountain slope. Why do you think so?
6Cirrus – highest clouds bring fair weather Review 13: WeatherCirrus – highest cloudsbring fair weatherCumulus – bright white wads of cottonseen with fair weather
7Review 13: WeatherStratus – form gray sheets that spread across the skyBring heavy mist and snowor drizzleCumulonimbus – largest clouds. Bring heavy rain, highwinds, hail and tornadoes.Describe the clouds you see outside.Do they fit any of the categories?
8Review 13: Weather7. Hail – when a raindrop freezes and forms an icy ball before falling to the ground.8. Sleet – when a raindrop falls from a cloud and passes through below-freezing air making a slushy blob.9. Snow – when ice crystals form in clouds and fall to the ground without melting.
9Review 13: WeatherMake a prediction. What kind of precipitation will fall if there are:Below-freezing temperatures in the cloudsTemp. barely above freezing on the ground?Describe the air temperature, precipitation, winds, and humidity during:Winter? Spring?Summer? Fall?
10Review 13: Weather Wind speed is described in miles per hour. Wind direction is the direction from which the wind blows.A north wind comes from the north.The tail points to where the wind is coming from.The barbs on the tail show the speed of the wind. More barbs – faster windThe dot points to the direction the wind is going.
11Tools to gather data about the weather: Review 13: WeatherTools to gather data about the weather:Thermometer – measures temperatureAnemometer – measures wind speed
12Tools to gather data about the weather: Review 13: WeatherTools to gather data about the weather:Rain Gauge – measures the amount of precipitationBarometer – measures air pressureWeather Vane –indicates wind direction
14Review 10: WeatherTornado – a small storm that forms funnel clouds of powerful winds, sometimes topping 300 miles per hour.Thunderstorm – a large storm bringing violent winds, heavy rain and lightning.
15Review 10: WeatherBlizzard – a strong winter storm that brings high winds, very cold temperatures and heavy snow.Hurricane – a severe tropical storm that brings strong, destructive winds and tidal surges.
16Review 10: WeatherFronts – lines that connect a very large mass of air having the same temperature, pressure and moisture.Warm front – front of a warm air mass. Brings steadier, lighter precipitation.Cold front – front of a cold air mass. Brings a drop in temperature and stormy weather.