Thursday, February 12, 2009

More On Severe Weather

There were nearly 400 reports of severe weather yesterday in the Ohio and Tennessee River Valleys as a squall line of severe thunderstorms passed through.

There were dozens of reports of tree and roof damage reported throughout the region.

CoCoRaHS observer Michael from Westmoreland, Tennessee lost a pear tree to the storm. Here is a link to his blog with a picture.

The CoCoRaHS observer near Scottsville, Kentucky lost part of their greenhouse roof!

Many of the comments mention winds in excess of tropical storm, and in some cases, hurricane strength.

Many also mention the rain measurements may not be accurate due to the winds blowing the rain horizontally at times.

So let's quickly talk about severe weather and what criteria must be met to classify a storm as "severe".

The National Weather Service has three criteria for a storm to be severe, and a warning will be issued when one or more have been met.

  • Hail 3/4" in diameter or greater (dime size approx.)
  • Winds greater than or equal to 58 MPH
  • Producing a tornado

    It looks like the weather will be a little more on the quiet side (in terms of widespread organized severe weather) for the next few days.

    In addition to the line of severe thunderstorms yesterday, it was just down-right windy across a large section of the eastern US.

    Look at the surface observations from mid-afternoon. Windy!!

    By the way, if you are not familiar with how to read a wind barb, here is a great link. Click here.
  • 1 comment:

    1. I encourage everyone to attend a NWS storm spotting class for their area. The storm spotters represent the "eyes and ears" reporting of severe weather in your area. And like CoCoRaHS, more volunteers equals better data, and better data in severe weather equals lives saved.