On average, the north Atlantic hurricane season produces 11 named storms, with six becoming hurricanes, including two major hurricanes. In 2005, the Atlantic hurricane season contained a record 28 storms, including 15 hurricanes. Seven of these hurricanes were considered "major," of which a record four hit 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," added Lautenbacher.
Warmer ocean water combined with lower wind shear, weaker easterly trade winds, and a more favorable wind pattern in the mid-levels of the atmosphere are the factors that collectively will favor the development of storms in greater numbers and to greater intensity. Warm water is the energy source for storms while favorable wind patterns limit the wind shear that can tear apart a storm's building cloud structure.
This confluence of conditions in the ocean and atmosphere is strongly related to a climate pattern known as the multi-decadal signal, which has been in place since 1995. Since then, nine of the last 11 hurricane seasons have been above normal, with only two below-normal seasons during the El Niño years of 1997 and 2002.
With neutral El Niño/Southern Oscillation (ENSO) conditions expected across the equatorial Pacific during the next three to six months, the NOAA Climate Prediction Center scientists say that neither El Niño nor La Niña likely will be a factor in this year's hurricane season. (Click NOAA image for larger view of conditions that will make 2006 an above-normal hurricane season. Please credit "NOAA.")
"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 National Hurricane Center. "One hurricane hitting where you live is enough to make it a bad season."
The north Atlantic hurricane season runs from June 1 through November 30. NOAA will issue a mid-season update in early August just prior to the normal August through October peak in activity.
The north Atlantic hurricane seasonal outlook is a product of NOAA's Climate Prediction Center, National Hurricane Center and Hurricane Research Division. The NOAA National Hurricane Center has hurricane forecasting responsibilities for the north Atlantic as well as the east Pacific regions.
NOAA, an agency of the U.S. Department of Commerce, is dedicated to enhancing economic security and national safety through the prediction and research of weather and climate-related events and providing environmental stewardship of the nation's coastal and marine resources.
Through the emerging Global Earth Observation System of Systems (GEOSS), NOAA is working with its federal partners, 61 countries and the European Commission to develop a global network that is as integrated as the planet it observes, predicts and protects.
Relevant Web Sites
NOAA North Atlantic Hurricane Outlook
NOAA Hurricanes Page (Links to 2005 NOAA Satellite Images)