How can I query for posts using a date stored in post-meta?

Question

I’m working on a games release feature for a website I’m building. So far everything is going smooth, but I’m stuck on one area. For the listings on the front end, I want it to look at the “release_date” field and only display games that have a release date >= that date.

I feel the code below should work, but it doesn’t return/display anything on the front end. And if I switch it to <=, it displays everything.

Any help would be greatly appreciated! Below is the query code.

$releasewindow = date('M j, Y', strtotime("-31 days"));
    
    $q = new WP_Query(array(
        'post_type' => 'game_release',
        'posts_per_page' => 5,
        'meta_key'  => 'release_date',
        'orderby'   => 'release_date',
        'order' => 'ASC',
        'meta_query' => array(
        array(
            'key'     => 'release_date',
            'compare' => '>=',
            'value'   => $releasewindow,
        )
    ),