The newest Macs (all of them) are incapable of running Snowy. I was a little confused by your question (confusion is my middle name) so I'll answer a possible alternative. The 13" non retina June 2012 MBP originally came with Lion. It won't run anything older than that.
Jon
macOS 11.7.10, iMac Retina 5K 27-inch, late 2014, 3.5 GHz Intel Core i5, 1 TB fusion drive, 16 GB RAM, Epson SureColor P600, Photoshop CC, Lightroom CC, MS Office 365
| 
