storm door

• storm-door (archaic)

storm door (plural storm doors)

1. A door normally leading to a storm cellar, cellar or a basement, for protection from a tornado or a violent storm.
2. A secondary door placed exterior to the primary door, to better weatherproof an entrance. Those storm doors that are also screen doors can be used for ventilation purposes when the primary door remains open. Typically found on front doors, rear doors, side doors, balcony doors.

• storm shutter

(door leading to a storm protected location):

• storm cellar

(secondary door for weatherproofing):

• storm window
• screen door
• aluminum door / aluminium door