Looking for a short story I read many years ago. As I recall, these anomalies would appear, and everyone was required to move to the centre in order to survive. But more than that, the anomalies exerted a sort of force that prevented you from ever moving further away from the centre — all houses had to be designed to have multiple exits to avoid trapping people, infants might be trapped out of reach, someone could get stuck just by taking a wrong turn, etc. (Breathing, circulation, etc. were fine.)
I'm wondering if this was compiled into one of the Year's Best Sci-fi anthologies by Gardner Dozois, but I've flipped through all the ones I can find on my bookshelves and nothing rings a bell.