Week display template missing variables

For the week display, I've worked with calendar-week-overlap.tpl.php to try to display the date in the date ("January 21, 2015") in the heading in addition to the weekday ("Wednesday"). The documentation at the top of this file refers to several promising looking variables: $rows['date'], $rows['datebox'], $min_date_formatted, but if I try to use them in this template file I get a PHP error stating that each of these variables does not exist!