The bigger the plant, the better it should be able to tolerate lower temperatures.
From asking a bunch of questions myself, I have concluded that as long as the plants do not experience long periods of low temperatures and the ground does not freeze, your plants should be fine although they may slow down in growth. If you do get freezing temperatures in your area, you can help protect the plants by wrapping their main stalk and the ground with something to hold in the heat. If you have access to electricity, you can plug in a small space heater or run a 100W incandescent in the lower branches of the plant to help keep the ground and stalk warm.
Once you get your first hard frost you should take a look at your plant. If the sun leaves (the big fan leaves) are looking wilty and watery, then you are done. You should go ahead and harvest. If your preventative measures kept the plant from going into shock, and the temps are back within the acceptable range, then you can leave the plant out for a bit longer.
Hope this helped!