Windspeed Estimate Video Scale?

[Dave Gallaher]

While watching Tornado Alley on IMAX last weekend and wondering what the windspeeds were in some of Casey's penetrated intercepts, I wondered if anyone has ever set up a reference page of videos that would represent different velocities by interaction with trees.

I recognize that a margin of error would be present depending upon tree species, growth age, terrain features, etc. But after all these years of storm videos, some good examples should be available from the ST archives.

I've sought to educate my own estimates by guessing, then verifying with measurements posted by NWS. It'd be nice to have a video scale that showed representatives of confirmed velocities. Perhaps some spotter trainings offer this? I don't think I've encountered it in the various spotter classes I've taken.

 

[Jeff Duda]

Starting at about 0:39 in this video, you'll see sustained winds over 50 mph with a gust to 61 mph. The picture quality wasn't great, and there aren't many objects to see affected, but it's something.

 

[Dave Gallaher]

Good start--thanks, Jeff. Looks like you guys had to eat some of that dust.

 

[Jeff Hawkins]

Being the novice that I am, this is an idea I've wondered about. Could a tornado be rated in a video based on what it does to trees. And not just interaction with trees, but with any object where the tor causes a change in said object.
I would think several possible factors would need to be accounted for: distance from the tor, lighting, video quality, surrounding meso components and larger regional weather phenomena...I'm sure others can add more criteria that would need to be considered. Given that, is the idea of using video to rate a tornado's wind speed impossible???....I've just blown my head apart...I need to go get a coffee now.

 

[Nicholas_Scherber]

I would think it is possible to get at least a rough estimate on windspeed by measuring how fast an object in the video is moving, however its probably not going to be very accurate. Still, this is a pretty interesting idea.