Displaying "open" or "closed" based on current Date/Time excluding Saturday and Sunday PHP

I am trying to display an "open" or "closed" graphic on a PHP page if the current date/time is between the stores opening times:

$mycurrentdateandtime = new DateTime();

$open = new DateTime( $mycurrentdateandtime->format('Y-m-d').' 09:30');
$close = new DateTime($mycurrentdateandtime->format('Y-m-d').' 17:00');

if (($mycurrentdateandtime >= $open) && ($mycurrentdateandtime <= $close)) {
    echo 'yes we are open';
} else {
    echo 'sorry we are closed';
}

I'm not great at PHP but the above works fine however I'd like to display "sorry we are closed" if it's either a Saturday or a Sunday. How can I edit the above code to check that?

Thank you. NJ