How strong are downburst winds?
Downburst wind speeds have been known to exceed 100 mph -- as strong as a tornado! Also, from a distance downbursts can sometimes look similar to tornadoes, as seen in the image on the left below.
The downdrafts can be as strong as 6,000 FPM. Horizontal winds near the surface can be as strong as 45 knots resulting in a 90 knot shear (headwind to tailwind change for a traversing aircraft) across the microburst.
downburst. a strong downdraft that originates within the lower part of a cumulus cloud or thunderstorm and descends to the ground, often resulting in strong straightline winds.
Wind speeds in microbursts can reach up to 100 mph, or even higher, which is equivalent to an EF-1 tornado! Winds this high can cause major damage to homes and other structures and level hundreds of trees. It is very important that you take Severe Thunderstorm Warnings just as seriously as Tornado Warnings!
Downburst is the general term for all localized strong wind events that are caused by a strong downdraft within a thunderstorm, while microburst simply refers to an especially small downburst that is less than 4 km across. A gust front is the leading edge of rain-cooled air that clashes with warmer thunderstorm inflow.
So it's all about the sustained wind speed when we're talking about the difference between breezy and windy, not the gusts. Breezy is described as a sustained wind speed from 15-25 mph. Windy is a sustained wind speed from 20-30 mph.
These downdrafts can be very powerful, with vertical winds of 6,000 ft per minute. When a strong downdraft, referred to as a downburst or microburst, hits the surface, the wind diverts horizontally outwards.
A severe downdraft and strong winds hit Pan Am Flight 759, causing the plane to crash shortly after takeoff. A similar catastrophe took place in 1985 in Dallas, Texas. A Delta Air Lines aircraft encountered a strong downdraft, leading to a loss of control, and crashed short of the runway.
Although microbursts are not as widely recognized as tornadoes, they can cause comparable, and in some cases, worse damage than some tornadoes produce. In fact, wind speeds as high as 150 mph are possible in extreme microburst cases.
Downbursts are sometimes described as a microburst when it covers an area of less the 2.5 square miles and last 3-7 minutes, or macroburst when they cover larger areas or last for more than 7 minutes. On rare occasions, downbursts can have wind speeds in excess of 150 mph.
What is the most intense type of downburst?
Most of the largest damage swaths are associated with derechos—a family of downburst clusters. The most intense winds associated with these larger downburst-producing storms appear to be associated with small-scale low-level rotation centers (i.e., embedded mesovortices).
Most downbursts are less than 4 km (2.5 mi) in extent: these are called microbursts. Downbursts larger than 4 km (2.5 mi) in extent are sometimes called macrobursts. Downbursts can occur over large areas.
A gale is a strong wind; the word is typically used as a descriptor in nautical contexts.
What is a Dust Devil? A common wind phenomenon that occurs throughout much of the world, including Arizona, are dust devils. An example of a dust devil can be seen to the left. These dust-filled vortices, created by strong surface heating, are generally smaller and less intense than a tornado.
See shelter immediately in basem*nt or interior room on lower level; take position under sturdy table. Stay away from windows, doors, outside walls; do not open windows. If not sheltered, lie flat in ditch with hands covering head. Avoid buildings with wide span roofs.
In other words, a downburst will appear as a circular area that is half red (which denotes air moving away from the radar) and half green (which denotes air moving towards the radar).
Though microbursts are rare and usually fairly short-lived, these vertical hurricanes can cause extensive damage.
At 32 to 38 mph, whole trees will be in motion, and you may experience some difficulty when walking into the wind. Trees that are already weakened or diseased may be at risk of falling or losing branches. At 39 to 46 mph, branches and limbs can be broken from trees.
47-54 Mph 75-88 kph 41-47 knots Strong Gale Slight damage occurs to buildings, shingles are blown off of roofs. High waves (6 meters), rolling seas, dense foam, Blowing spray reduces visibility. 55-63 Mph 89-102 kph 48-55 knots Whole Gale or Storm Trees are broken or uprooted, building damage is considerable.
While the most damaging winds are classified as those at 50 mph or stronger, you can see serious damage at much lower wind speeds than that. Gusts often outdo the sustained wind speed, making wind speed forecasts a shaky ground for comfort. Even gusts of 20 mph or so can be dangerous under the right circ*mstances.
What is the difference between a downburst and a microburst?
However, most downbursts are smaller than 2.5 miles in diameter - these are called microbursts. Because of their intense winds, destructive capabilities, and relatively small scale, microbursts may often be confused with tornadoes - but they are very different phenomenon.
Besides the obvious downdraft that could push you into the ground, the massive wind shear across the microburst can cause you to stall, and adds to your descent rate. Here's an example flight through a microburst, step-by-step.
A Cessna 172 flipped over when a gust of wind swept through John Wayne Airport Monday morning. No injuries were reported. Above, private planes are shown parked at the airport. A gust of wind flipped over a single-engine plane at John Wayne Airport Monday morning, but the pilot avoided any injury.
For all intents and purposes, a plane cannot be flipped upside-down, thrown into a tailspin, or otherwise flung from the sky by even the mightiest gust or air pocket. Conditions might be annoying and uncomfortable, but the plane is not going to crash.
There are many factors to consider when choosing between a range hood or a downdraft vent, but it ultimately gets down to your household's cooking habits. For regular meals, without a lot of open flame or flying grease, downdraft vents are quiet and efficient solutions.
