Radiation Storm in Fallout 4 is a random, emergent environmental effect that can be quite deadly to the player.
- A Radiation Storm's arrival is marked by a yellowing of the sky as the storm approaches. It also emits a unique thunder/explosion sound which is hard to miss.
- If the player is caught outside while the storm passes, they will incur Radiation damage over the duration of the storm.
- Going inside a building (that requires a load screen) can provide protection. Structures that can be walked into without loading do not seem to offer protection. As long as your location is considered to be the Commonwealth, you are vulnerable.
- Equipping Power Armor offers protection against the radiation effects.
- A Hazmat Suit is also useful if you have one in your inventory.
- Assault Gas Mask is a useful headgear during these storms.