Impact-based warnings

A traditional forecast says what the atmosphere will do. An impact-based warning says what that will mean on the ground — which roads flood, which crossings close, which sea conditions stop a fishing trip.

Every Grenada Meteorological Service warning is built around real hazard likelihood and impact, not meteorological thresholds alone.

The matrix is a guide, not a rule. A duty forecaster may raise or lower a level where operational experience justifies it, and records the reason on the warning.

Local knowledge matters here: a river crossing that has failed twice this season carries a higher impact than its rainfall total alone would suggest.