Watch- Issued when the risk of a hazardous weather or hydrologic even has increased significantly, but it's occurrence, location, and/or timing is still uncertain.  It is intended to provide enough lead time so those who need to set their plans in motion can do so.

Warning- Issued when a hazardous event is occurring or has a very high probability of occurrence.  Warnings advise of a threat to life or property.

Advisory- Issued when a hazardous event is occurring or ahs a very high probability of occurrence.  Warnings advise of a threat to life or property.

Advisory- Issued when a hazardous event is occurring or has a very high probability of occurrence.  Advisories describe events that cause significant inconvenience.