There is No Bad Light for Street Photography.
How true. Todays cameras, at least those in the last 3 years or so make shooting at high iso under low light conditions easy. Unlike years ago when high iso produced noise in digital or grain in film today you have much greater control of the look especially in black and white work.
I think this article I am linking you to touches on some very interesting philosophies and techniques in regards to “street photography.”
Remember even on vacation life on the streets will add flavor to your normal travel pics.
Give it a try.