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[IDV #QHV-523927]: Plotting observerd wind barbs in m/s

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  • Subject: [IDV #QHV-523927]: Plotting observerd wind barbs in m/s
  • Date: Tue, 30 Sep 2008 10:32:09 -0600
Hi Bill-

> Full Name: Bill Bauman
> Email Address: address@hidden
> Organization: NASA/AMU
> Package Version: 2.5 build date:2008-05-08 07:05 UTC
> Operating System: Windows XP
> Hardware: Java: home: C:\Program Files\IDV_2.5\jre version: 1.6.0_01 
> j3d:1.5.1 fcs (build6)
> Description of problem: I'm plotting wind tower mesonet observations.
> 
> I've converted the observations from kt to m/s (to include mean wind speed 
> and peak wind speed) in the data file..
> 
> When I plot the observations, the wind barbs are plotted in kt instead of m/s.
> 
> I don't see an option in the plot model to force the barbs to plot in m/s - 
> is there a way to do so?
> 
> In the attached file showing the plotted observations, the top number is peak 
> speed in m/s, the middle number is mean speed in m/s and the bottom number is 
> the tower identifier.

By definition, there is no distinction in a barb representation of
winds based on units.  A long flag is 10 kt and a short flag is 5 kt.

So, a 8 m/s wind will look the same as a 15 kt wind:

\
 \_\____

since 8 m/s is ~16 kt.

(how's that for ASCII art? ;-))

I'm assuming you are plotting the mean speed so to me they look correct.

I used to have a good web reference on this, but can't find it right now.
The closest I could come up with is:

http://cimss.ssec.wisc.edu/tropic/other/faq_winds.html

Don







Ticket Details
===================
Ticket ID: QHV-523927
Department: Support IDV
Priority: Normal
Status: Open