Greetings.
You may have heard of CloudSat, a recently commissioned satellite with a powerful 90GHz RADAR for profiling the moisture content of clouds.
The other day I discovered a site where "First Look" cloudsat data can be downloaded:
http://www.cloudsat.cira.colostate.edu/dpcstatusQL.phpFrom memory cloudsat is in an orbit which repeats every 14 or 16 days so coverage is fairly limited and, my location at least, only has passes during the early morning hours, so it may not be all that useful for disecting afternoon thunderstorms.. but it's still groovy nonetheless.
Best wishes,
Dave