Hodographs

[Ryan Wichman]

Can anyone help me understand hodographs a little better? I have very limited knowledge on how to read them. I have tried to ask around with some of the other meteorology students here at Western Illinois University and no one seems to have a really good grasp on them. Thanks

[Chris Bowman]

A hodograph is a plot of wind vectors with their tails at the center of the plot and end point pointing from the direction the winds are from. Generally only the end point is plotted and then to finish the graph the dots are connected. Then you plot your storm motion. When you plot line segments going from the storm motion to any wind vector endpoint, that area is the amount of helicity.

As far as trying to read a hodograph it can be kind of tricky. For tornadoes something that looks like a fish hook would be ideal. The comet module "convective storm matrix (http://www.meted.ucar.edu/convectn/csmatrix/)" does a good job of illustrating the types of storms associated with a general shape of a hodograph.

Here is a good .PPT (http://www.google.com/url?sa=t&ct=res&cd=5&url=http%3A%2F%2Fkkd.ou.edu%2FMETR4433_Spring_2008 %2FHodograph_and_Rotation.ppt&ei=XpEaSOixLJT8gQTCg6y4Dg&usg=AFQjCNGaxJptOezCEYOBUk0jyLRfIMwCYg&sig2=beNSGZhZbW7_1pX1-VU1oQ) about hodographs from I am guessing a lecture from OU.

[Brent Gilles]

Just to add to that storms tend to be more linear when the hodograph is more of a straight line, but definitely check out the comet module, its good stuff.