[Barquito]

Second is Weather Underground. It really doesn't make much difference - it's all based on the same NOAA weather radar systems.

That's true, but, some of the sites have things like probability cones. That is nice to get an idea about where a storm is going. You can do this (and I often do), by looking at the NWS radar in motion, and figuring out what speed the storm is going. It is just easier if the web site does it for you.