How to control block stacking order in mobile layout

I have blocks arranged in a grid on a page (3 blocks across, 3 blocks down) when I switch to mobile layout and the blocks are rearranged into a single column, they do not appear in the order that I want. Is it possible to manually order the items in mobile layout?

I've had this problem before, you have to snap them in place. The bar that comes up when you're splitting into more columns, you have to put the one that you one to show up next, so that the snap bar comes up. 

The full bar will place that image directly after that whole column in the mobile order. The half bar will place that image after the image in mobile order.

Hope this helps!

Thank you! I appreciate your quick response with a simple explanation. That worked perfectly!

yay! glad I could help! Your site looks beautiful by the way 

Thank you. I'm no expert but I'm slowly getting there.