The National Hurricane Center will in the future maintain any necessary hurricane watches or warnings even if a storm is no longer technically a hurricane, as in the case of Superstorm Sandy.
Center officials made the changes permanent Friday in light of confusion over alerts issued as Sandy approached in October. The new policy aims to ensure the public is aware of the dangers a storm might pose, regardless of where it fits within meteorological taxonomy.
Some criticized the center after Sandy devastated parts of the New Jersey shore, New York and Long Island because a hurricane warning was not issued ahead of the storm. As Hurricane Sandy approached the East Coast, it began to lose some "tropical" cyclone characteristics, meaning while it still packed dangerous winds and heavy precipitation, it was behaving more like a winter storm than a hurricane.
The policy change gives hurricane center forecasters the option of keeping those warnings in place, "in those cases when the system continues to pose a significant threat to life and property," National Oceanic and Atmospheric Administration officials said.
When Sandy struck, a hurricane warning was warranted when sustained winds 74 mph or higher were imminent and associated with tropical or subtropical cyclones. The new policy adds "post-tropical" cyclones to that definition. Similar changes apply to hurricane watches and tropical storm watches or warnings.
Separately, the hurricane center is also exploring widening the scope of its tropical storm forecasting. The forecast looks 48 hours ahead and issues a probability that any active weather systems might develop into a cyclone; a proposed change with expand that window to five days.
The center is also slightly reducing the size of forecast cones it issues, which show the scope of the possible track a storm could take.