https://www.gamespot.com/articles/fortnites-new-limited-time-mode-steady-storm-avail/1100-6461003/

Fortnite's 5.20 update has arrived for PC, PS4, Xbox One, Nintendo Switch, and iOS. On top of introducing a new weapon and an assortment of gameplay tweaks to Battle Royale mode, it marks the start of the game's latest limited-time event: Steady Storm.

As its name implies, Steady Storm mode features one storm that continuously closes in on the island over the course of the entire match. Unlike a typical game of Battle Royale, there are no safe zones in Steady Storm, so players will have to stay on the move and keep track of the storm on the map in order to survive.