- var_dump: documentation ( source)
- preg_match: documentation ( source)
<?php
$str = 'September 14-20, 26, 28-30, October 1-8, 10, 11, 15-20, 24, November 25, 28-30';
preg_match('/(\w+)\s(\d+)/', $str, $pieces);
$first_month = $pieces[1];
$first_day = $pieces[2];
var_dump($first_month, $first_day);