Tropical cyclones with an organized system of clouds and thunderstorms with a defined circulation, and maximum sustained winds of 38 mph (61 kph) or less are called “tropical depressions”. Once the tropical cyclone reaches winds of at least 39 mph (63 kph) they are typically called a “tropical storm” and assigned a name.

If maximum sustained winds reach 74 mph (119 kph), the cyclone is called:

A hurricane in the North Atlantic Ocean, the Northeast Pacific Ocean east of the dateline, and the South Pacific Ocean east of 160°E, (The word hurricane comes from the Carib Indians of the West Indies, who called this storm a huracan. Supposedly, the ancient Tainos tribe of Central America called their god of evil “Huracan”. Spanish colonists modified the word to hurricane.),

A typhoon in the Northwest Pacific Ocean west of the dateline (super typhoon if the maximum sustained winds are at least 150 mph / 241 kph),

A severe tropical cyclone in the Southwest Pacific Ocean west of 160°E or Southeast Indian Ocean east of 90°E,

A severe cyclonic storm in the North Indian Ocean, and

Just a tropical cyclone in the Southwest Indian Ocean.
Hurricanes are further classified according to their wind speed. The Saffir-Simpson Hurricane Scale is a 1-5 rating based on the hurricane’s present intensity. This is used to give an estimate of the potential property damage and flooding expected along the coast from a hurricane landfall.

Wind speed is the determining factor in the scale, as storm surge values are highly dependent on the slope of the continental shelf in the landfall region. Note: all winds are using the U.S. 1-minute average.

Kicking off National Hurricane Preparedness Week, the U.S. National Weather Service (NWS) announced its predictions for the 2006 Hurricane Season on Monday. Forecasters indicate the chance of strong hurricanes hitting along the Atlantic Coast of the United States is about 80 percent above normal for 2006. The north Atlantic hurricane season runs from June 1 through November 30.

This year, the National Oceanic and Atmospheric Administration (NOAA) is expecting an active season predicting 13 to 16 named tropical storms with eight to 10 becoming hurricanes. Of those, four to six could become major hurricanes of Category 3 strength or higher.

In 2005, of an unprecedented 28 storms and 15 hurricanes, with four major hurricanes hitting the United States.

“Although NOAA is not forecasting a repeat of last year’s season, the potential for hurricanes striking the U.S. is high,” said retired Navy Vice Adm. Conrad C. Lautenbacher, Ph.D., undersecretary of commerce for oceans and atmosphere and NOAA administrator.

In the month’s following last year’s major hurricanes Katrina, Rita and Wilma the Red Cross served more than 50 million meals and snacks, lent financial aid to more than 1 million people and had more than 3 million overnight stays in its shelters. As the recovery efforts continue in the gulf coast region, the Red Cross urges everyone to be prepared for what storms this year’s hurricane season may bring.

“Whether we face an active hurricane season, like this year, or a below-normal season, the crucial message for every person is the same: prepare, prepare, prepare,” said Max Mayfield, director of the NOAA Hurricane Center. “One hurricane hitting where you live is enough to make it a bad season.”

Hurricane Preparedness Week runs from May 21 through May 27 with the goal of providing the public with useful knowledge about hurricane hazards that can be used to take action and prepare. By knowing your vulnerability and preparing yourself and your loved ones, you can greatly reduce some of the devastating effects of a major hurricane.

NCDC is the world’s largest active archive of weather data. NCDC produces numerous climate publications and responds to data requests from all over the world. NCDC operates the World Data Center for Meteorology which is co-located at NCDC in Asheville, North Carolina, and the World Data Center for Paleoclimatology which is located in Boulder, Colorado.

NCDC supports a three tier national climate services support program the partners include: NCDC, Regional Climate Centers, and State Climatologists.

The National Climatic Data Center (NCDC) is the Nation’s Scorekeeper in terms of addressing severe weather events in their historical perspective. As part of its responsibility of “monitoring and assessing the climate,” NCDC tracks and evaluates climate events in the U.S. and globally that have great economic and societal impacts. NCDC is frequently called upon to provide summaries of global and US temperature and precipitation trends, extremes, and comparisons in their historical perspective.