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There is a lot more work that goes into preparing people for hurricanes than just the forecast. Risk communication is critical, and language barriers as well as cultural and operational differences between countries are major challenges.

The National Hurricane Center (NHC) handles naming, categorizing and forecasting tropical systems in the Atlantic and Eastern Pacific Basins. For people in the United States, Puerto Rico and U.S. territories, the NHC also issues watches and warnings for tropical systems.

An explanation of the NHC’s watches and warnings is given at the bottom of this page, as well as the process for issuing them.

For other nations of the Caribbean, however, it is up to the individual governments to issue their own watches and warnings based on information they receive from the NHC.

“Some countries are reluctant to issue warnings for their people unless the storm coming at them is a very bad one”

This can present challenges at times due to language barriers and cultural and operational differences between the NHC and these other countries.

“Some countries are reluctant to issue warnings for their people unless the storm coming at them is a very bad one,” said Mike Brennan, Senior Hurricane Specialist with the NHC.

“The Caribbean countries take our forecast suggestions and make the decision on whether they are going to issue a watch or warning,” Brennan added. “NHC does not issue watches and warnings for other countries.”

Brennan explained how there was a case when a country changed a warning to a watch because their emergency personnel were not yet prepared to go to a warning. Instead, a watch was issued for a few hours before a warning was posted.

Language barriers are another challenge with many countries throughout the Caribbean being French- and Spanish-speaking. As a result, the NHC has a number of employees who speak more than one language.

Four of the NHC’s forecasters speak both English and Spanish. The NHC also has a Mexican Air Force meteorologist who helps coordinate aircraft reconnaissance missions in and around Mexico.

Process for Issuing Watches and Warnings

The NHC calls each country’s meteorology office to coordinate watches and warnings about 90 minutes before the issuance of an advisory.

The NHC then has a conference call with the National Weather Service one hour before the release of a forecast to brief everyone affected on the movement of the storm and its potential future.

Definitions from the National Hurricane Center

Hurricane Warning:

An announcement that hurricane conditions (sustained winds of 74 mph or higher) are expected somewhere within the specified area. Because hurricane preparedness activities become difficult once winds reach tropical storm force, the hurricane warning is issued 36 hours in advance of the anticipated onset of tropical-storm-force winds.

Hurricane Watch:

An announcement that hurricane conditions (sustained winds of 74 mph or higher) are possible within the specified area. Because hurricane preparedness activities become difficult once winds reach tropical storm force, the hurricane watch is issued 48 hours in advance of the anticipated onset of tropical-storm-force winds.

Tropical Storm Warning:

An announcement that tropical storm conditions (sustained winds of 39 to 73 mph) are expected somewhere within the specified area within 36 hours.

Tropical Storm Watch:

An announcement that tropical storm conditions (sustained winds of 39 to 73 mph) are possible within the specified area within 48 hours.

Advisory:

Official information issued by tropical cyclone warning centers describing all tropical cyclone watches and warnings in effect along with details concerning tropical cyclone locations, intensity and movement, and precautions that should be taken. Advisories are also issued to describe: (a) tropical cyclones prior to issuance of watches and warnings and (b) subtropical cyclones.