When using a date as part of a filename or directory name, you should follow the format yyyyMMdd (at least in that order). I cringe every time I find some other formats. Having the date in this format allows it to be sortable.
20171014 is easier to work with than 10_14_17.
While we’re on the topic, you should be using 24 hour time formats too.
Trump : "We can wipe North Korea off the map."
"Can you get supplies to Puerto Rico?"
Trump : "It's not that easy because of a big ocean."