WEATHER -the state of the atmosphere at a specific time and place -air pressure, wind, temperature, and humidity - The SUN provides most of Earth’s energy, driving the water cycle

AIR TEMPERATURE A measure of how much molecules are moving Higher temp = faster moving, far apart molecules Lower temp = slower moving, closer together molecules

Anemometer- an instrument that measures wind speed Caused by air moving from areas of high pressure to areas of lose pressure Anemometer- an instrument that measures wind speed

The amount water vapor present in the air HUMIDITY The amount water vapor present in the air Warmer temperatures allow for the humidity of air to be higher Condensation occurs when there is enough water vapor in the air for it to be saturated Relative humidity- the measure of the amount of water vapor present compared to the amount needed for the air to be saturated at a specific temperature

The TEMPERATURE at which air is saturated and condensation occurs It changes with the amount of water vapor in the air

Form as warm air is forced upwards, expands, and then cools CLOUDS Form as warm air is forced upwards, expands, and then cools Made of billions of tiny droplets of water attached to small particles of dust or salt that are suspended in the air 3 main types

STRATUS Form at low altitudes and are associated with fair weather, rain, or snow

CUMULUS masses of puffy, white clouds, with flat bases Found at great heights Associated with fair weather and thunderstorms

CIRRUS Fibrous and curly High, thin, white, feathery cloud made of ice crystals Associated with fair weather and can indicate approaching storms

PRECIPITATION Water falling from clouds Rain- temperature above freezing Snow- water vapor turns directly to a solid Sleet- starts as rain but then freezes on the way down Hail- lumps of ice