Hi,
you can read it directly in the Output Window (remember that this window is independent from the GUI panels, so you can access it even while the GUI is popping up anything...), but if the number of warnings exceeds the default threshold (5), then you will miss the others. In this case, ANSYS writes in the Output Window something like "NNN warnings encountered [..]. 5 displayed, others may exist. Please check the [log] / [err] file". In fact, they are also recorded in the LOG file (the file which has the same name of your running job, and the ".log" extension) and / or the ERROR file (same thing, but with ".err" extension).
As regards the Output Window: my advice is to set it "as big as you can" on the monitor, and to expand the buffered number of lines to something like 5000 (it will only take some more memory to the operating system, but being it only ASCII characters it results in a very small consumption); don't forget to tell the OS to "remember these settings for all applications with the same name".
Regards