Although the impending hurricane has huge potential to wreck havoc, for those of us who like to paddle whitewater rivers, big rain events such as these have a bit of a silver lining. The game always has been to figure out where the rivers are coming up and just how much. GIS offers some tools to help this process exponentially.
Although I have quite a few ideas for greatly streamlining, automating and making this process quite a bit more powerful, here is an example of what can be accomplished in about 15 minutes of work.
The data is downloaded directly from NOAA. This is predicted rainfall five days out, speculating the effects of the approaching hurricane. Laid underneath this are watershed boundaries to easily see which side of the ridge it is raining on. All of this was created using free services on ArcGIS.com. I did not use any desktop or server software besides the website. If you want to see this full screen, a web application is available here.
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