dias-de-la-semana.php

<?php

$timezone = new DateTimeZone('America/Santiago');
$now = new DateTimeImmutable('now', $timezone );

$dds = $now->format('N');

switch ( $dds ){
	// sabado
	case 6:
		$hoy = $now;
		$manana = $hoy->add( new DateInterval('P2D', $timezone) );
		break;
	// domingo
	case 7:
		$hoy = $now->add( new DateInterval('P1D', $timezone) );
		$manana = $hoy->add( new DateInterval('P2D', $timezone ) );
		break;
	default:
		$hoy = $now;
		$manana = $hoy->add( new DateInterval('P1D', $timezone ) );
		break;
}

$dia_hoy    = $hoy->format('N');
$dia_manana = $manana->format('N');