TEST 8: Std. 3, Obj. 2 Review
Cloudy – chance of storms What kind of weather comes with a low pressure system? Cloudy – chance of storms
What instrument measures air pressure? Barometer
What instrument measures relative humidity What instrument measures relative humidity? (Hint: Our recent lab activity.) Psychrometer!
If the barometer reading falls, what do we know about the weather? Storm’s a-comin’!
What will warm, moist air moving over a mountain range do? Clouds!
What do we call precipitation that falls through freezing air close to the ground? Sleet!
If enough energy is absorbed by liquid water, what happens to the water? Evaporation = Gas
What kind of storms do cold fronts produce? Short, Violent
Large Area, Sometimes Violent What kind of storms do warm fronts produce? Large Area, Sometimes Violent
When warm air moves into cold air, that is called a . . . Warm Front
When cold air moves into warm air, that is called a . . . Cold Front
*Cold air mass advances *Runs into warm air mass Describe what happens during a cold front. *Cold air mass advances *Runs into warm air mass *Lifts warm air mass up
How do winds in the Northern Hemisphere move in a low pressure system? Counter-clockwise
How do winds in the Northern Hemisphere move in a high pressure system? Clockwise
Warm, Moist Air Cold Air The most severe thunderstorms are caused by . . . Cold Air Warm, Moist Air
What determines the type of air mass that forms? Location!
*water temperature changes slowly *this stabilizes the air temperature What makes areas by the ocean warmer in winter and cooler in summer, compared to inland areas? Oceans: *water temperature changes slowly *this stabilizes the air temperature
Temperature Drops Water Condenses What happens when an air mass moves upward quickly? Temperature Drops Water Condenses
What does “nimbo-” or “-nimbus” (as in cumulonimbus clouds) mean? Rain-producing
What kind of clouds bring thunderstorms and/or hail? Cumulonimbus!
Why are weather satellites better than ground instruments? Broad Area
Location, Extent, Movement What information can Doppler radar give us? Location, Extent, Movement
What do meteorologists make from their computer data to help them forecast the weather? Computer Models
What are you measuring when you collect data such as air pressure, humidity, temperature, etc.? Weather!
Watch out – storm’s comin’! How does Doppler radar save lives? Watch out – storm’s comin’!
Bounces radio waves off precipitation How does Doppler radar measure snow or rain? Bounces radio waves off precipitation
What do all the weather stations, world-wide, do with the information they collect? Share It!
High pressure equals . . . Cold!
High pressure equals . . . Cold air sinking
Low pressure equals . . . Warm!
Low pressure equals . . . Warm air rising
*warm, moist air rises fast How does a hurricane form? *warm, moist air rises fast *moisture condenses *latent heat released
Canada’s cold, dry air runs into warm, moist air from Gulf of Mexico Why do the mid-central United States have more tornadoes? Canada’s cold, dry air runs into warm, moist air from Gulf of Mexico Spring and early summer – Tornado Alley
True or False: A tornado travels a predictable path if it touches down.
Oceans add water vapor and Why do hurricanes develop over oceans? Oceans add water vapor and energy to an air mass.
*air sinks and flows outward What is an “anticyclone”? *opposite of cyclone *air sinks and flows outward *brings dry weather
In the United States, what direction do air masses move In the United States, what direction do air masses move? (Hint: Same as wind.) West East
Look at this weather map. What do the “L” and “H” indicate? Pressure!
What do meteorologists use on a weather map to convey information? Colors! Symbols!
What is this air mass called and which way is it moving? Cold Front
What is this air mass called and which way is it moving? Warm Front
What is this air mass called and which way is it moving? Occluded Front
Dude, it ain’t goin’ nowhere! What is this air mass called and which way is it moving? Stationary Front Dude, it ain’t goin’ nowhere!
Temperatures will rise. What will temperatures in Chicago be like in the next few days? See the warm front? Temperatures will rise.