How can I create an effect cross breeze?

Question

We are shutting the air of at night to save money. I have been told by several people opening all windows will not allow a cross breeze to form. What is the best way to do this? I am not concerned about a breeze in the whole house just two upstairs bedrooms. Should I just crack those window? really open those windows? do I need another open for some reason?

Answer 1

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Answer 2

~~We put a box fan in one window upstairs blowing out, then open the remaining windows. You will get a very strong breeze and it pulls the cool air in through the open windows. We do the same for downstairs. It's way colder and breezier than we could ever afford to set our a.c. at!~~