Installation And Requirements
From WeatherCat Wiki (Mahler)
WeatherCat version 1.00 will run on computers running Mac OS X version 10.5 or later (PowerPC & Intel). Note that WeatherCat version 1.1 will drop PowerPC support as development moves from XCode 3 to XCode 4. Version 1.xx will still be available for purchase for those wishing to run on an older computer.