I'm not aware of any changes for warm vs. cold regions starting from model year 2012. Per https://www.autoblog.com/2011/07/19/2012-nissan-leaf-higher-price-tag-standard-equipment/, CWP became standard w/model year 2012.
http://www.mynissanleaf.com/viewtopic.php?t=4404 has some details on the...