Display posts from today and future in Elementor ‘posts widget’

Here is the working solution:

add_action( 'elementor/query/my-custom-query', function( $query ) {  

    $meta_query = $query->get( 'meta_query' );
$query->set( 'date_query', array(
    array(
            'after' => date('l, F jS, Y', strtotime('+0 day')),
        )
    ) ); 
} );

You can change the strtotime (+1 day….+n day ….-n day) to fetch the event’s date you’re looking for.

The date format here is (‘l, F jS, Y’), you may change based on your WordPress setting (Dashboard >setting >General)
Elementor query id: my-custom-query