be in the calm before the storm

To be in a period of inactivity or tranquility before something chaotic begins. Likened to a literal period of calm before a storm begins. Oh, things are quiet now, but we're just in the calm before the storm—the dinner rush will turn this place into a mad house. Activists are preparing for a massive legal battle over the proposed legislation. They say that we're currently in the calm before the storm. When there's only a few minutes until an event is set to start, you realize that you're in the calm before the storm and you get a rush of adrenaline.