Do the many bulbs that are rising up to 8″ out of the ground need to be covered since the forecast has temperatures down to 17 degrees F these next few mornings?
The bulb foliage should be fine as it is. Any flowers, on the other hand will probably turn to mush. If you’re feeling protective or nervous you may want to cover up the foliage with burlap, cloth rags, sheets, etc. Once the clouds come back you can remove the protection.
Here is an article on predicting frost from Michigan State University.