
It's because you have lost the weight.
That fat kept you warm. I live in the midwest and since I gained all this weight I can go the whole winter without being very cold. I used to visably shake, but no more. All this padding keeps me insulated. I can go outside in 30 degree weather and never button up my coat.It's the only thing I will regret about losing the weight.
But, I won't be a hot, sweaty mess in the summer!!!!