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This is reposted from the storm forum by Ed Dunham, as the winter storm is affecting much of the south, Its the start of a New Year and time to consider the initial outlook for tropical cyclone activity during 2014 in the Atlantic basin. After three highly active years from 2010 to 2012, tropical cyclone activity dropped quite a bit during the 2013 season. Although there were 13 named storms - a slightly above normal number, the season produced just two hurricanes and no major hurricanes. Last year in the Outlook I noted that there has never been 4 seasons in a row with a high level of activity and 2013 kept that premise intact. With only two hurricanes, the Accumulated Cyclone Energy (ACE) for the basin was quite low - and 2013 was not an El Nino year. The downward trend in activity is likely to continue for two reasons: 1) the latest NCEP SST Forecast issued on December 30th, 2013, predicts Northern Hemisphere ENSO neutral conditions for the Spring of 2014 and El Nino conditions in the 3.4 region for the Summer of 2014. The NCEP Forecast seems reasonable, and there is a good chance that at least a Moderate El Nino will exist for the August through October peak of the Atlantic hurricane season. 2) 2013 was the first year since 1994 without a major hurricane (the last season with just two hurricanes was 1982). With the expectation for lower tropical cyclone totals in the Atlantic basin in 2014, its quite possible that the so-called 25-year cycle of peak activity in the basin (which actually has never been exactly 25 years) could be over. Unlike recent years when it was difficult to pinpoint a good analog year, 2014 has a bunch of them. The best analog seems to be 1963 - here is the list with corresponding storm totals: 1. 1963 9/7/2 2. 1979 9/5/2 3. 1982 6/2/1 4. 1968 8/4/0 5. 1991 8/4/2 6. 2002 11/4/2 With western Atlantic SSTs expected to remain on the warm side during the 2014 season, I'll lean toward the first two analogs with an initial slightly below normal outlook of 9 named storms and 5 hurricanes with 2 of the hurricanes reaching major hurricane status of Cat III or higher (9/5/2). If the trend toward a more significant El Nino becomes evident in the late Spring, the final forecast may require a downward adjustment. We typically have a mini contest for season numbers, which you can see in the Storm Forum. |