change time zone and set time zone to UTC

 <?php

$date = new DateTime();

$date->setTimezone(new DateTimeZone('America/Los_Angeles'));

echo $fdate = $date->format('Y-m-d H:i:s');

echo date('Y-m-d H:i:s T', time()) . "<br>\n";

date_default_timezone_set('UTC');

echo date('Y-m-d H:i:s T', time()) . "<br>\n";

?>