FOR IMMEDIATE RELEASE
Contact: Susan Harrison
Even though the 1999 Atlantic hurricane season has produced one named tropical storm to date, National Oceanic and Atmospheric Administration scientists still expect a busier-than-normal hurricane season across the North Atlantic Ocean and Caribbean Sea during the peak period from mid-August through mid-October. In an update to the hurricane outlook NOAA released in May, scientists still say three or more intense Atlantic storms are possible this season, and residents living in communities along the East and Gulf coasts should remain prepared.
"Last year we had fourteen named storms, and the first hurricane (Bonnie) didn't develop until mid-August," said Gerald Bell, a research meteorologist at NOAA's Climate Prediction Center. "This year, many of the most prominent atmospheric and oceanic factors that can generate tropical storm and hurricane activity in the Atlantic basin are already in place, and are expected to persist through the season. Just because we haven't seen a hurricane yet this year, don't get fooled into thinking that this will be a light season."
Those factors, Bell said, include: low wind shear across the tropical Atlantic, below average air pressure across the tropical Atlantic Ocean and Caribbean Sea, a structure and location of the African easterly jet, which may provide energy to developing storm systems, and above average sea surface temperatures across the tropical Atlantic Ocean and Caribbean Sea.
Bell added that "the expected continuation of these conditions is based on their strong link to existing patterns of tropical rainfall and cooler-than-average tropical Pacific Ocean temperatures (La Niña), both of which are expected to persist through the remainder of the hurricane season." La Niña refers to cooler-than-average sea-surface temperatures across the central and eastern tropical Pacific Ocean, which historically have contributed to a greater number of hurricanes in the Atlantic.
Last year, the CPC issued its first-ever Atlantic hurricane outlook in August and accurately forecast an above-normal number of tropical storms and hurricanes for the remainder of the season. In all, the 1998 hurricane season produced 14 tropical storms, including three major hurricanes. These storms inflicted $7.3 billion in damages and 23 fatalities in the United States alone.
In an average season, the Atlantic Basin experiences between five and six hurricanes, two of which are severe and 1.5 storms make land fall.
Bell said two additional factors -- reduced wind shear over the Caribbean Sea and a northward extension of deep tropical moisture and rainfall to the hurricane development region -- that are typically observed during active hurricane seasons are not yet in place, but are expected to develop during the coming weeks.
Residents living in hurricane-vulnerable areas should remain vigilant, said Jerry Jarrell, director of NOAA's National Hurricane Center. "With only one tropical storm so far, the potential remains high for considerable activity in the 10 weeks remaining in the most active part of the typical season."