Understanding Weather Carin Miranda Smyrna Middle School Winter 2013

Water in the Air Evaporation is when water changes from a liquid to a gas. When air reaches its dew point relative humidity is at 100%

Clouds Nimbostratus clouds will bring light to heavy continuous rainy weather. Cumulonimbus clouds are large thunderstorm clouds that produce precipitation. Altocumulus clouds are puffy mid-level clouds. Cirrus clouds are high clouds made of ice crystals.

Precipitation Sleet-Starts as rain then freezes in the air. Snow-Water vapor changes directly into a solid because of cold temperatures. Hail-Forms when precipitation is sent back up into the clouds many times.

Air Masses Continental polar (cP) dry and cold Maritime polar (mP) wet and cold Continental tropical (cT) dry and warm Maritime tropical (mT) wet and warm C=dry P=cold M=wet t-=warm

Fronts Warm front-warm air moves over cold air and replaces it. Stationary front-Not moving. Brings many days of cloudy, wet weather. Cold front-cold air mass displaces a warm air mass. Occluded front-warm air mass is caught between two cold air masses and is forced to rise. Lots of precipitation.

Meteorology Images of weather systems on television come from weather satellites. From a weather map you can tell the locations of cold and warm fronts. The lines connecting points of equal pressure on weather maps are called isobars. Isobars help meteorologists by showing areas of high and low pressure.

Vocabulary Humidity Air mass Front Barometric pressure Meteorologist Psychrometer

Vocabulary 2 Thermometer Barometer Anemometer Rain Gauge Wind Vane Wind

Vocabulary 3 Hygrometer Weather Relative Humidity Condensation Cloud Precipitation