Downburst
A Downburst is created by an area of significantly rain-cooled, descending air that, after hitting ground level, spreads out in all directions producing strong winds. Often confused with tornados.
Updraft
Updrafts are found when a wind blowing at a hill or mountain has to rise to climb over the hill. Updrafts can also be caused by the sun heating the ground. The heat from the ground warms the surrounding air, which causes the air to rise. The rising pockets of hot air are called thermals.
Wind Shear
Wind shear is caused by a change in wind speed and/or direction resulting in a change in headwind or tailwind that can displace an aircraft abruptly from its intended flight path, requiring substantial control action to be taken.