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20051221: NLDN data access in NOAAPORT

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  • Subject: 20051221: NLDN data access in NOAAPORT
  • Date: Thu, 22 Dec 2005 01:00:53 -0700
>From: Deirdre Garvey <address@hidden>
>Organization: NCAR/RAL
>Keywords: 200512220023.jBM0Ne7s000956 IDD lightning

Hi Deirdre,

>Is there any way to the get the 1-minute NLDN data from the NOAAPort
>via the LDM?  Tim Alberta told me to contact you.

The lightning data is available in the IDD HDS datastream.  Please
note, however, that this data is encrypted.

Here is a brief note about the lightning data extracted from:

http://www1.ncdc.noaa.gov/pub/data/documentlibrary/tddoc/td9603.pdf

  1. Abstract: These lightning data are incidents of lightning strokes that
  have been detected by the U.S. National Lightning Data Network (NLDN) sensors
  and by lightning detectors outside the Continental U.S. These data are
  retrieved from NOAAPORT and are encoded in binary. U.S. data are identified
  by their message ID SFUS41 and non-U.S. data by their message ID SFPA41.
  Decoder software developed at the National Climatic Data Center (NCDC)
  converts the binary format to a formatted ASCII record. A detailed
  description of the ASCII record are provided below.
  
  2. Element Names and Definitions:
  POS: 1-4
  Year
  The year the data were observed. A four-digit number.
  
  POS: 5-6
  Month
  The month the data were observed. Range of values are 01 to 12.
  
  POS: 7-8
  Day
  The day the data were observed. Range of values are 01 to 31.
  
  POS: 9-10
  Hour
  The hour the data were observed. Range of values are 00 to 23.
  
  POS: 11-12
  Minute
  The minute the data were observed. Range of values are 00 to 59.
  
  POS: 13-14
  Second
  The second the data were observed. Range of values are 00 to 59.
  
  POS: 15
  Not Used
  
  POS: 16-24
  Latitude
  Latitude of the lightning stroke. Format XXX.XXXXX.
  MIN: -90.00000 MAX: 90.00000
  
  POS: 25
  Not Used
  
  POS: 26-35
  Longitude
  Longitude of the lightning stroke. Format XXXX.XXXXX.
  MIN: -180.00000 MAX: 180.00000
   ...

You can verify that you are receiving the data using the LDM 'notifyme'
utility:

<as 'ldm'>
notifyme -vxl- -f HDS -p SFUS41
notifyme -vxl- -f HDS -p SFPA41

>Thanks for your help,

No worries.

Cheers,

Tom Yoksas
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