Meteorologists with the National Weather Service say a derecho is to blame for a deadly disaster in Houston, Texas yesterday that cost 7 lives and billions of dollars in damages.

According to the National Weather Service, a  derecho (pronounced similar to “deh-REY-cho”) is a widespread, long-lived wind storm that is associated with a band of rapidly moving showers or thunderstorms. Although a derecho can produce destruction similar to the strength of tornadoes, the damage typically is directed in one direction along a relatively straight swath. As a result, the term “straight-line wind damage” sometimes is used to describe derecho damage. By definition, if the wind damage swath extends more than 240 miles  and includes wind gusts of at least 58 mph (93 km/h) or greater along most of its length, then the event may be classified as a derecho.

The Houston office of the National Weather Service says there was straight-line winds up to 100 mph spread throughout downtown Houston. They also said straight-line winds near Baytown and the Galena Park area were clocked at 90-100 mph. An EF-1 rated tornado also touched down near Cypress; that tornado had winds estimated of 110 mph.




The wind storm which leveled power lines outside of Houston and blew out numerous windows in the city is responsible for claiming the lives of seven people. Houston officials said that fallen trees were responsible for 2 deaths, a crane accident was responsible for 1,  1 was killed when trying to move an energized electrical pole, and another was killed after lightning struck and ignited the trailer she was in. Authorities said that another victim lost his life while trying to get power to his portable oxygen tank.

Today, Houston mayor John Whitmire  signed a Declaration Proclaiming a Local State of Disaster for the City of Houston. This creates a path for additional authority and resources from both state and federal partners to assist with citywide storm recovery.