php time zone strings america code example
Example: Pacific Daylight Time Zone php
date_default_timezone_set('America/Los_Angeles'); // or wherever you are
$time = time();
if ($time >= strtotime("Second Sunday March 0") && $time < strtotime("First Sunday November 0"))
{
echo date('m/d/y h:i a', $time);
} else {
echo date('m/d/y h:i a', $time);
}