Considering the temperatures we're expecting overnight, you can put the feeders into totes and put them outside in the shade.
Alternatively, fill some empty 1-2 liter plastic bottles with water, put those outside, and put the bottles in the freezer once the water has frozen. Swap bottles as needed.
You can also pre-emptively set all of your refrigerators and freezers to their lowest setting right now so that the contents stay cold longer.