you probably want to get both dates into timestamp format, using the mktime() function. then you can compare them with the current timestamp, which you can get from the time() function. adding one day to the current timestamp would just mean adding 24 hours' worth of seconds, with consideration for daylight savings time if need be.
$date1 = mktime($hour, $min, $sec, $mo, $day, $year);
$now = time();
if ($date1 >= $now)
{
...
}