By default, sort performs a string sort. If you want it to do a numeric sort, you have to do something like this.

popup_menu(-name=>"month_array",
           -values=>[sort { $a <=> $b } %month_array],
           -labels=>\%month_array,
           -default=>$mon,
           -class=>"formfield")
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Since the keys are the numbers 1-12, you could also try -values=>[1..12] and forget the sort.

---
print map { my ($m)=1<<hex($_)&11?' ':'';
$m.=substr('AHJPacehklnorstu',hex($_),1) }
split //,'2fde0abe76c36c914586c';
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