Wednesday, June 12, 2013

Wild weather night ahead to our north

All the pieces are falling in place for a night of very violent weather to our north, across parts of the Midwest, Great Lakes and Ohio Valley.

Remember the word "derecho."  Those of you who follow weather closely are already familiar with the term.

Many forecasters believe a derecho will form Wednesday evening and surge across Illinois, Indiana and Ohio, leaving a long trail of wind damage.

At mid-afternoon Wednesday, the Storm Prediction Center in Norman, Okla., said it was preparing to issue a tornado watch for parts of Iowa and Illinois. A low pressure system is expected to slide southeast from the Dakotas, moving into the Great Lakes.

Meteorologists say a few tornadoes could form initially, but they expect the storm complex to morph into a line of powerful thunderstorms later in the evening. A derecho is a term used for a long-lived line of damaging thunderstorms. There are numerous recorded accounts of a derecho lasting for hundreds of miles, covering several states.

Derecho thunderstorm winds typically are in the range of 60 to 80 mph, about the same as a weak tornado and plenty strong enough to leave millions of people without power. Sometimes those winds reach 100 mph.

Meteorologist Bernie Rayno of Accu-Weather said Wednesday morning that he expects the worst damage to be in a corridor between Interstates 70 and 80. The Storm Prediction Center has taken the unusual step of placing that area at "high" risk of severe weather later today. That "high risk" category is used only a few times each year.

People who live in or near Chicago, Indianapolis, Louisville, Cincinnati and Columbus will be most at risk. But wind and hail damage, along with flooding rain, also is possible in places like Detroit, Cleveland and Pittsburgh.

The next question is what happens Thursday.

Earlier this week, it appeared as if another outbreak of widespread severe weather would develop in the Carolinas -- as part of a much larger system stretching from New York City down to South Carolina on Thursday. But some of the more recent computer models have indicated the Carolinas could be in the middle of a weather sandwich, with severe storms to the north (Middle Atlantic) and south (Gulf coast) and the Charlotte region catching a break.

We'll watch that development over the next 12 to 18 hours.


Anonymous said...

You asked us to "remember" the word. Then never bothered to actually tell us what it is. So here goes:

"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(backward "C") form of squall line, forming in an area of wind divergence in the upper levels of the troposphere, within a region of low-level warm air advection and rich low-level moisture."

Charlie Tombassio said...

My friend and I were talking about derecho on our way to the store a few days ago, so Steve's post is ironic to us. My friend and I are also from Ohoi, so we think Steve is great!

Anonymous said...

Ok, we have remembered derecho. So where is it??

Anonymous said...

It came. It too, uh huh.

Anonymous said...

Hey Steve,

Did anyone send you a picture of the weird clouds yesterday? There was one big white cloud that looked like a snake and stretched for miles. Was that the derecho?

Charlie Tombasio said...

The derecho actually looked very much like a pelican holding a tennis racquet. My friend and I saw it.

Anonymous said...

Ed Clark! Where are you Ed Clark?