A microburst is a small, very intense downdraft that descends to the ground resulting in a strong wind divergence. The size of the event is typically less than 4 kilometers across. Microbursts are capable of producing winds of more than 100 mph causing significant damage. The life span of a microburst is around 5-15 minutes.
When rain falls below cloud base or is mixed with dry air, it begins to evaporate and this evaporation process cools the air. The cool air descends and accelerates as it approaches the ground. When the cool air approaches the ground, it spreads out in all directions and this divergence of the wind is the signature of the microburst. In humid climates, microbursts can also generate from heavy precipitation.
Also Known As: downburst
Examples: A downburst is defined as a strong downdraft with an outrush of damaging winds on or near the ground. If the swath is less than 2.5 miles, it is called a microburst. Microbursts are quick-hitting events and are extremely dangerous to aviation. Microbursts are sub-classified as dry or wet microbursts, depending on how much rain accompanies the microburst when it reaches the ground.