I believe an ideal scenario would be wind driven snow blowing off the frozen parts (preventing the insulating properties of snow) and slushing up the open water. That slushed up water will now freeze. Hopefully working to lock up the body of water.
Hamilton res had a bunch of open areas and wide cracks with water. After a few squalls and cold nights, the open parts are smaller and the cracks are frozen solid.
I was there this morning and I was able to fish in places I couldn't a few days ago. Ice is still pretty thin in places but it was cold today and upcoming forecasts show it getting ALOT colder.