This is kind of a cool tool. Does lots of things, but it also shows total estimated precip from up to the past 72hrs. You can reduce that down to the last 1hr, 3hrs, etc. You can also go as far back as one week to look at data. You can zoom in pretty close, and include county lines, etc.
https://mrms.nssl.noaa.gov/qvs/product_viewer/