$re = '/((?:\d{6}?)([A-Z\d]{3})?(?:[\^r\ ]+)(([A-Z\d]{6}|[A-Z\d]{5} |[A-Z\d]{4} ))?)/m';
$str = 'FPCN54 CWNT 080810^r^r EXTENDED FORE
ASUS42 KMHX 080425^r^r RWRMHX^r^r WEAT
RXUS30 KWNO 081300^r^r XOBUS ^r^r <?xm';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php