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Calculate the length of hail paths

2 messages · Barry Rowlingson, St John Brown

Original
Barry Rowlingson
# 
I downloaded the hail and tornado shapefile It looks like hailstorms in the
original data files don't really move, except maybe one 10m grid square.
This first one from 2013 goes nowhere:

Slot "coords":
         [,1]      [,2]
[1,] 185758.3 -246307.6
[2,] 185758.3 -246307.6

I reckon theyve tried to use the same format as the tornado data, which can
have quite large differences between start and end point, but hailstorms
are such a short intense event that the motion isn't important relative to
the size.

So I don't think there's essentially any "track" information in the data,
and it should be considered point events.

Barry




On Mon, Oct 27, 2014 at 2:49 PM, St John Brown <st_john_brown at yahoo.com>
wrote:

  
  


  


    

    

      
      

        


  

        

      St John Brown
    

    

      
      #
    

  


  

      
Frede and Barry,

Thank you very much for your responses. I spoke directly with the NOAA person responsible for maintaining the data. He said that the spatial lines do not represent paths, but point observations. I made an assumption that the lines were hail paths because there was no text describing the data. I close my question.

Thank you,

St. John

        
On Tuesday, October 28, 2014 4:47 AM, Barry Rowlingson <b.rowlingson at lancaster.ac.uk> wrote:

        
I downloaded the hail and tornado shapefile It looks like hailstorms in the original data files don't really move, except maybe one 10m grid square. This first one from 2013 goes nowhere:

Slot "coords":
         [,1]      [,2]
[1,] 185758.3 -246307.6
[2,] 185758.3 -246307.6

I reckon theyve tried to use the same format as the tornado data, which can have quite large differences between start and end point, but hailstorms are such a short intense event that the motion isn't important relative to the size. 

So I don't think there's essentially any "track" information in the data, and it should be considered point events.

Barry

        
On Mon, Oct 27, 2014 at 2:49 PM, St John Brown <st_john_brown at yahoo.com> wrote:

        
Hello,