Ohio State Vegetable Specialist Robert Precheur explains the 'Super Derecho'
From The Ohio State University Extension Vegetable Crops VegNet newsletter Vol. 19(13), July 10, 2012. Online at http://vegnet.osu.edu
Sources: Accuweather.com, NOAA, Wikipedia
While you probably have another “D” word or adjective in mind to describe the storm that hit OH on June 29th the correct meteorological term is “derecho”. A derecho is a widespread, long-lived, straight-line windstorm that is associated with a fast-moving band of severe thunderstorms.
Generally, derechos are convection-induced and take on a bow echo form of squall line, forming in an area of divergence in the upper levels of the troposphere, within a region of low-level warm air advection and rich low-level moisture. The June 29th storm went 700 miles from Indiana to the mid-Atlantic coast in just 12 hours at an average speed of 60-65 miles per hour. Check out the radar graphic from NOAA. Wind gusts were clocked at the Ft Wayne, IN airport at 91 mph and the Columbus airport at 80 mph, equivalent to a category 1 hurricane. It maintained this violent wind even when it reached Tuckerton on the south Jersey coast where gusts were clocked at 81 mph.
In Ohio, the violent wind snapped power poles in half, blew tractor trailers off the road and quickly took down trees, leaving many without electric power for a week or more. The electronic news zipper on the Columbus Dispatch building in downtown Columbus said on Friday night, over 10 million people were without power from the mid-west to the mid-Atlantic coast.
|Two-foot diameter oak trees fell like dominoes, and |
many, at dangerously high levels requiring special attention.
|Pepper plants laid over exposing fruit to sunburn.|