Weather is an all-encompassing term used to describe all of the many and varied phenomena that can occur in the atmosphere of a planet. The term is normally taken to mean the activity of these phenomena over short periods of time, usually no more than a few days in length. Average atmospheric conditions over significantly longer periods are known as climate. Usage of the two terms often overlaps and the concepts are obviously very closely related.
Basic mechanism
Weather phenomena result from temperature differences around the globe, which arise mainly because areas closer to the tropics, around the equator, receive more energy from the Sun than more northern and southern regions, nearer to the Earth's poles.
Weather & Natural Disasters Coverage | NewsHour with Jim Lehrer | PBS
Gustav Returns to Hurricane Strength, Heads Toward Gulf Coast The storm Gustav strengthened back into a hurricane Friday as it left Jamaica and headed for the Cayman Islands, still on track to reach the U.S. gulf coast by Tuesday, the National Hurricane center said Friday. Hurricane Katrina's Aftermath The days after Hurricane Katrina made landfall in Greater New Orleans, the normally lively city was eerily empty, save for law enforcement officers, military and journalists. Follow a reporter's journey through the city after the storm. Three Years After Katrina, New Orleans Braces for Another Storm Almost exactly three years after Hurricane Katrina inundated New Orleans, the city's residents and officials are preparing for the possible arrival of another strong storm.
