Hurricane Forecast Boosted: 11 to 14 More Storms Expected
Posted on August 2, 2005
The National Oceanic and Atmospheric Administration has boosted the total number of storms they expect this season. 18-21 storms with 5-7 major hurricanes are now expected after the season got off to a quick start with 7 storm by the end of July. That leaves 11-14 more storms for the rest of the season which includes the most active months of August, September and October. There is a 95% to 100% chance that this will be an above normal season according to NOAA.
For the 2005 Atlantic hurricane season the outlook calls for an extremely active season, with the seasonal ACE index forecasted to range from 180%-270% of the median. This range is above the 175% baseline that Goldenberg et al. (Science, 2001) use to define a hyperactive season. The outlook also calls for a seasonal total of 18-21 tropical storms, with 9-11 becoming hurricanes, and 5-7 of these becoming major hurricanes [categories 3-4-5 on the Saffir-Simpson scale]. Because the ACE index does not directly account for the numbers of tropical storms, hurricanes, and major hurricanes, the predicted ACE range can verify even if these numbers fall outside their predicted ranges.Update: The Seattle Times has more on the forecast upgrade.This forecast reflects NOAA’s highest confidence of an above-normal hurricane season since their outlooks began in August 1998. This prediction also reflects a continuation of above-normal activity that began in 1995, and will likely be the seventh extremely active season since 1995.
Even though there has already been considerable early season activity (7 tropical storms, with two becoming major hurricanes), most of the activity is still expected to occur during the climatological peak months of August-October. Many of the storms during this period will develop from disturbances moving westward from the west coast of Africa, and will likely form over the tropical Atlantic Ocean and Caribbean Sea in the region between 9°N-21.5°N (black box). Historically, tropical storms that first form in these areas account for 55% of all hurricanes and 80% of all major hurricanes. They also account for nearly the entire difference in hurricanes and major hurricanes between above-normal and below-normal hurricane seasons.
