Conditions of readiness
From Glossary of Meteorology
conditions of readiness
In the U.S. Navy, those preliminary measures prescribed for a given area in anticipation of hazardous and destructive weather phenomena.
The conditions are IV, III, and II for possible threat of destructive winds (of force indicated) within 72, 48, and 24 hours, respectively, and condition I for imminent destructive winds within 12 hours.