A continuation of warmer-than-normal Atlantic Ocean temperature anomalies into the summer and fall and the likelihood of a favorable or neutral wind shear environment on the heels of the current La Nina event will bring an active 2008 Atlantic hurricane season, WSI Corp. forecasters said Wednesday.
WSI's forecast calls for 14 named storms and seven hurricanes, including three intense hurricanes (Category 3 or greater) during the coming Atlantic hurricane season. The forecast numbers are all larger than the 1950-2007 averages of 9.7 named storms, 5.9 hurricanes and 2.3 intense hurricanes. Hurricane season runs from June 1 to Nov. 30.
"Since 1995, most tropical seasons have been more active than the long-term averages, due to warmer Atlantic Ocean temperatures," said WSI seasonal forecaster Todd Crawford. "We do not see any reason why this active regime will not continue in 2008. The current La Nina event, which will likely decay this spring, should leave behind a wind shear environment that is favorable for the development of tropical systems in the summer and fall of 2008."
WSI predicted 15 named storms and eight hurricanes, including four intense hurricanes, prior to the start of the 2007 hurricane season. Like most forecasters, WSI's preseason prediction was somewhat higher than the numbers the season actually produced: 15 named storms and six hurricanes, including two intense hurricanes -- with only one minor hurricane, Humberto, making landfall in the United States (see related story). In an Aug. 14 update, WSI reduced its forecast numbers to 14 named storms and six hurricanes including three intense hurricanes.
Last month weather forecasters at Colorado State University (CSU) predicted a somewhat above-average 2008 hurricane season, calling for 13 named storms and seven hurricanes, including three major hurricanes (see NGI, Dec. 10, 2007). The CSU forecasters said their analysis was based on a new statistical forecast technique that explains a considerable amount of hurricane variability in hindcasts issued from 1950 to 2007.
The CSU hurricane forecast team also predicted a 60% chance that at least one major hurricane will make landfall on the U.S. coastline this year. The long-term average probability is 52%. For the U.S. East Coast, including the Florida peninsula, the probability of an intense hurricane making landfall is 37%; for the Gulf Coast from the Florida Panhandle west to Brownsville, in southernmost Texas, the probability is 36%, it said.
At the conclusion of the 2007 hurricane season, scientists with the National Oceanic and Atmospheric Administration (NOAA) said they were reviewing a set of dynamic weather patterns to understand why there was lower-than-expected hurricane activity in the Atlantic Basin (see NGI, Dec. 3, 2007). The United States was "largely spared" from significant landfalling storms, but "several noteworthy events took place, including two back-to-back Category 5 hurricanes hitting Central America and the rapid near-shore intensification of the single U.S. landfalling hurricane," NOAA noted. Like the WSI and CSU teams, NOAA had forecast above-average hurricane activity at the beginning of the 2007 season (see NGI, May 28, 2007) before eventually trimming its storm prediction.
WSI is scheduled to issue an update to its 2008 tropical season April 22.
©Copyright 2008 Intelligence Press Inc. All rights reserved. The preceding news report may not be republished or redistributed, in whole or in part, in any form, without prior written consent of Intelligence Press, Inc.