However, there is a disagreement between warning centers on the nature of the system.

Scientists and military chiefs studying the threat are calling for a global warning centre to be set up to inform governments immediately of asteroid impacts.

The warning centre said there was no wider tsunami threat to Pacific coastlines.

Generally, when a tropical storm moves from a warning centre's area of responsibility to another, its original name will be retained.

During 1957, hurricanes that formed east of 140 W were not given names by the local warning center.

Below is a summary of the classifications used by the official warning centres worldwide.

Reports among warning centers often differ; as such, information from all three agencies has been included.

All data is taken from the warning centers from the region unless otherwise noted.

Leisurely radar training continued and the recently organized early warning center was left minimally staffed.

No cyclones were named by this warning centre during the 1997-98 season.