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This site is being migrated from my previous wiki at

For the Eclipse on August 21, 2017 please see Eclipse 2017


I am a trained Skywarn spotter. See What is Skywarn for more information.

Here is a script I use to alert me on days that spotter activation may be required based on the NWS HWO product for my forecast office (WFO or WSFO).

The HWO or Hazardous Weather Outlook is created daily by your local forecast office. In it is always a mention of Skywarn Spotter activation.

Even if you are not a trained spotter it is still good to know the outlook of the area where you will be that day. I travel fairly enough and visit relatives across several geographical areas. I can modify my script on a given day to include additional forecasts by the local WFO when I am traveling. Or I can put in the URL below (modify the "issuedby=" in the URL) and change the WFO or simply visit the top site at and put in the zip code or city name for your current location and click down to Hazardous Weather.

Since I spend 90% of my time in Deltona, FL and 10% in Greeneville, TN (I own property in each) I monitor both offices statements.

The two offices I monitor are Melbourne, FL coded as "MLB" at and Morristown, TN coded as "MRX" at

The text only HWO for MLB is at

The text only HWO for MRX is at

There is also a RAW text source for MLB but I am not sure how long it will last:



Notice the "issuedby=" in the URL. That is where you would put in the code for your local forecast office. Forecast offices nearest you and their codes can be found at

The output of the script is sent to via email daily at 7:30am via cron (in Linux)

30 7 * * *  /home/kinscoe/bin/ | mailx -s "Daily Hazardous Weather Outlook" -r 2>&1

This script runs in Linux Bash shell ( however it can also run in Mac (which already has Bash installed) or Windows using the Cygwin install. For Cygwin see For the Mac (and Linux as well if you do have these dependencies installed) the script should work fine but you will also need to install curl and html2text. Curl is likely already installed on both Mac and Linux by default. It has been on the Mac since 10.8 I believe. For Linux consult your distribution for the proper way to install Curl or visit the source code download at html2text may be slightly harder to obtain. You can visit the source code page at In Mac you can obtain a port using Macports or Homebrew. I recommend Homebrew. In Homebrew I used the command

brew install html2text

The Bash shell script:

The script is now at Github.

The output which I will see in email similar to (actual email received 2017-07-20):

HWO statement for MLB...

Spotters are requested to monitor the weather and self activate
if needed. In addition, please report any rainfall amounts greater
than 3 inches to the National Weather Service.

For full outlook click on

HWO statement for MRX...


Spotter activation will not be needed.

For full outlook click on 

This could also be sent to Twitter or other such alerting media.


Nexrad Radar

IMG 0003r.jpg

"NEXRAD or Nexrad (Next-Generation Radar) is a network of 158 high-resolution Doppler weather radars operated by the National Weather Service, an agency of the National Oceanic and Atmospheric Administration (NOAA) within the United States Department of Commerce. Its technical name is WSR-88D, which stands for Weather Surveillance Radar, 1988, Doppler. NEXRAD detects precipitation and atmospheric movement or wind. It returns data which when processed can be displayed in a mosaic map which shows patterns of precipitation and its movement. The radar system operates in two basic modes, selectable by the operator: a slow-scanning clear-air mode for analyzing air movements when there is little or no activity in the area, and a precipitation mode with a faster scan time for tracking active weather. NEXRAD has an increased emphasis on automation, including the use of algorithms and automated volume scans. Second generation NEXRAD radar systems will have the capability to optically detect hailstone size down to the square mile." - Intellicast

Details on the NEXRAD system are available in Federal Meteorological Handbook No. 11.

There are additional handbooks (publications) available for download from the Office of the Federal Coordinator for Meteorology (

Four volumes are available:

  • A - System Concepts, Responsibilities, and Procedures
  • B - Doppler Radar Theory and Meteorology
  • C - Products and Algorithms
  • D - Unit Description and Operational Analysis

The official Interface Control Documents (ICDs) contain detailed information on the binary data formats and product specifications.


Public -


Weather Radar Applications -

The netCDF data format ( is a set of software libraries and machine-independent data formats that support the creation, access, and sharing of array-oriented scientific data. The Java NEXRAD Viewer allows users to export Level II or Level III radar data into netCDF format for later manipulation using programs such as MATLAB.

Archived data




My code (to be migrated from SVN) is at