bring it inside if you can...give it more time the leaves will fall I noticed some of the more "common" plumerias can handle cold more than your fancy or harder to find ones.

Trip, your plant looks great! They will go dormant, I don't necessarily believe in forcing them into dormancy. I think Walley is right, some can handle it longer than others, and if you have one of those great hardy ones, let it weather the storm, or cut the leaves and bring it inside. (stop watering if you go that route)

Wendy

Thanks friends
I am relieved after knowing that this is common.
Decided not to interfere and let her slip into dormancy on it's own.Watering will be reduced to cope up with changed scenerio

Trip, I was looking closer at the pic, it almost looks like a Singapore, they don't typically loose leaves during the winter. Hard to tell with the pic, but just a thought in case you never loose em and start to worry.

Wendy

You may be right Wendy
I have seen few grown up trees at my place who had not shed their leaves.Maybe my plumie is also of that family