Dr. William Gray and Philip Klotzbach at Colorado State University have issued their long range forecast for seasonal hurricane activity in the Atlantic for next year.
They are calling for 13 named storms next season. The long term climatalogical average is 9.6. The team at CSU predicts 7 of the cyclones will grow to become hurricanes. The long term average is 5.9. They forecast 3 intense hurricanes (SSHS Category Three or higher.)
So, their prognostication is that the seasonal storm counts will be higher than normal. This same trend carries over into their forecast for some of the other parameters, including 30 hurricane days (average is 24.5) and ACE or Accumulated Cyclone Energy. This index combines the duration and intensity of the tropical cyclone activity for the year to deliver a truer picture of the intensity of the season. This year, the ACE index is projected by the CSU team to be 115. The long term average is 96.1.
In 2007, the counts were above normal, but below the seasonal forecasts issued by the CSU Tropical Meteorology Project. But the tropical cyclones in 2007 were short lived and despite having two category five hurricanes make landfall for the first time in recorded history, generally on the weak side. In fact, some have questioned whether all of the named storms should have been named.
As far as landfalls of a major hurricane on the U.S. coast, Gray and Klotzbach’s team say the probability is 60% this year. The average for the last century is 52%. They say the probability of a Gulf landfall from the Florida Panhandle west to Brownsville is 36%. The long term average in 30%.
So the first prediction for the 2008 North Atlantic Hurricane Season is that it will again be an above normal year. They base their forecast on many factors, including above normal Atlantic sea surface temperatures and expected La Nina conditions. Keep in mind that the TMP forecasts have shown little more skill than climatology this far out. The main purpose of the seasonal forecasts is to focus coastal communities on preparedness. Even in a slow year, one landfalling major hurricane can make it a bad year. Remember, 1992 was a slow season, save for a storm named Andrew.
