Phase

Definition:

No hazard.

Precaution

--- Be Alert ---

Possible occurrence (lower than 30%) of a certain natural hazard within 8 to 24 hours.

Watch

---Prepare Yourself---

Conditions of a natural hazard are possible (30 to 50%) within next 3 to 12 hours.

Advisory

--- Protect Yourself--

Conditions of a natural hazard are imminent (higher than 50%), within 1 to 2 hours.

Warning

--- Protect Yourself---

Conditions of a natural hazard are imminent (higher than 50%), within 1 to 2 hours and pose a larger threat.