I'm not familiar enough with your area to know whether tulips would have to be lifted and stored for the winter or not. I can
tell you that you should allow the leaves to die back before you dig the bulbs. That is how the bulb stores enough food to support the flowers for the next year.
Just leave the bulbs where they are until the leaves turn yellow and then brown. When the leaves look dead, and you can pull them loose with a gentle tug, it will be time to dig and store your bulbs. If none of the members here can advise you on whether to dig the bulbs or leave them in the ground, you can always ask at a good nursery in your area (not a big box type of store, but a real nursery), or else just phone your local Extension service.