Web alarm clock for 2:30 a.m.
Before handing the watch to someone else, you set a 2:30 am alarm so the windows are secured before the typhoon arrives. The handover should name which rooms still need checking, especially any jalousie windows that may look shut but are not fully latched. That leaves the next person with a clear task to finish before 3:00 am rather than repeating your whole inspection.
While passing responsibility for the windows, check where the alarm sound will actually play. A phone may quietly remain connected to earphones, so the person taking over might never hear the alert from across the room. Disconnect them or test the alarm aloud before you step away. Keep the browser running and the phone awake as well: if either stops, the alarm cannot prompt the window check.
Typhoon preparations at this hour are easier when the route through the house is already visible. Before your shift ends, switch on a hallway light or place a charged lamp where the next person can reach it without searching. Keep glare away from the windows so reflections do not hide movement outside, and leave curtains positioned so every latch can be checked quickly at 2:30 am.