gistfile1.txt

$myposts = get_posts( $args );

$fri =  date('Y-m-d',strtotime('friday this week'));
$sat =  date('Y-m-d',strtotime('saturday this week'));
$sun = date('Y-m-d',strtotime('sunday next week'));

// one of the posts dumped in this has the "single date" array
var_dump($myposts);
 
 
  foreach ( $myposts as $post ) : setup_postdata( $post );
  	$customdates = get_post_meta($post->ID,'custom_date', true);
  	
  	//$customdates is what is tossing the error 
  	foreach ($customdates as $eventday)
  	{
  	switch ($eventday) {
  	    case $fri:
  	        $friray[]=$post->ID;
  	        break;
  	    case $sat:
  	        $satray[]=$post->ID;
  	        break;
  	    case $sun:
  	        $sunray[]=$post->ID;
  	        break;
  	}
  	
   	}