The Java-based animation script that the NWS RIDGE Radar pages has been using for years, is no longer supported. In order to maintain functionality of the pages, that portion of the page has been switched over to a Flash-based version.
The look and feel of the mechanism remain largely unchanged. The only exception to that, is the way in which you "un-zoom."
Use the Left click to zoom.
"Ctrl" + Left click to zoom out