What Are Straight-Line Winds?
How To Recognize And Be Prepared For Downburst Wind Damage
Sep 3, 2008
Straight-line winds are caused by a storm front, and can have gusts of 100 mph or more. They can be accompanied by hail or large rain drops, or be dry. They often strike without warning and cover a much larger area than a tornado. Particularly large straight-line winds can be known as a derecho, from the Spanish word for straight.
What Are Straight-Line Winds?
Sometimes the damage from a straight-line wind is so great that people will claim it came from a tornado, but it's easy to tell which caused the destruction after the storm. Straight-line winds are similar to tornados as far as having the same wind speeds and same amount of damage, but tornadoes destroy with circular winds, and are most often found in the rear of severe storms. Straight-line winds do damage that appears more like that of a hurricane with trees and crops laying flat in a single direction.
The most likely cause of a straight-line wind in a storm is from a downburst, which is colder air being forced down vertically in front of a storm. Once the downburst hits the ground, either on land or water, it has nowhere else to go, and is forced along the ground at great speed.
Unfortunately, unlike tornadoes which can be tracked with decent accuracy, downbursts are more unpredictable and may develop before the television and radio weather teams have time to put out a warning. Also, it's believed that downbursts are the reason some boats and airplanes have disappeared without warning in the past, and why they have crashed during otherwise calm weather.
How To Prepare For Downbursts And Straight-Line Winds
Those living in a storm-prone area can take the same steps they would to protect themselves from a tornado, such as designating a storm area.
The key is to plan in advance and take steps to get to get settled into a safe place well ahead of the storm, instead of waiting for tornado warnings or the television alerts. A good storm preparedness packet includes: A flashlight, first-aid kit, battery-powered radio, bottled water and maybe even some non-perishable food.
Meteorologist Jeff Haby gives several tips on how to reduces damage from straight-line winds in his article "What Are Straight-Line Winds" on the Ultimate Weather Education Website. He says that when a storm is coming, residents should secure lawn furniture and ornaments. Before a storm, they can keep trees pruned and take down any trees that are unhealthy and could be knocked easily into the house.
