Although the 2008 Atlantic Basin Hurricane Season doesn't officially start until June 1st, meteorologists have developed predictions for the number of hurricanes.

Colorado State University’s Department of Atmospheric Science hurricane research team issued a revised bulletin for the 2008 Atlantic Basin Hurricane Season on April 9, 2008. Instead of the previous prediction of 13 Named Storms and 7 Hurricanes made in December 2007, the team is now predicting 15 Named Storms and 8 Hurricanes this summer.

Atlantic Basin Seasonal Hurricane Forecast

The forecast for the 2008 hurricane season now includes:

• 15 named storms
• 80 named storm days
• 8 hurricanes
• 40 hurricane days
• 4 intense hurricanes (Category 3, 4, or 5)
• 9 intense hurricane days

The Net Tropical Cyclone (NTC) activity is predicted to be 160 percent of normal (100 percent) for the long term average. Climatology data results average 5.9 hurricanes each season, 9.6 named storms and 2.3 intense storms (Category 3, 4, or 5).

The Tropical Meteorology Project - CSU

Hurricane season predictions from Colorado State University’s “Tropical Meteorology Project” rely on 58 years of data and atmospheric and ocean measurements. Using statistical forecast methodology, hurricane activity predictions are made to benefit human curiosity. CSU has correctly predicted hurricane activity for 45 out of 58 seasons. Heading the project, Professor William Gray has made predictions for 25 years, and has researched tropical meteorology for more than 40 years.

According to the meteorologists, some of the factors determining a lower frequency of hurricanes include:

• Cooler Atlantic Ocean temps
• Drier mid-level atmosphere over Atlantic Ocean
• Higher tropical Atlantic sea level pressures
• Stronger tropical Atlantic vertical wind shear
• Warmer sea surface temperatures in the tropical eastern and central Pacific

The effects of El Nino or La Nina also have an impact on the frequency of hurricanes. EL Nino creates warmer water, and stronger winds that rip tropical depressions apart before they become tropical storms or hurricanes. La Nina creates cooler water, resulting in more hurricanes.

NOAA also makes hurricane season predictions, which are due out in May. NOAA uses more general terms to describe the outlook, rather than a specific number, such as:

• Average
• Above-average
• Below-average

In 2007, NOAA predicted an above-normal hurricane season, with 13-17 named storms, 7-10 hurricanes, and 3-5 major hurricanes

Another producer of hurricane season forecasts is the UK's Tropical Storm Risk (TSR) program. The British venture forecasts an active hurricane season for 2008, estimated 35 percent above the norm. The Tropical Storm Risk forecast for the Atlantic Basin was issued several days before the revised predictions from Colorado State University's team. The TSR predictions are based on trends, climatology data and scientific measurements, such as trade wind speed.

Hurricane Terms Defined

The term “Named Storms” refers to tropical storms or hurricanes. Hurricanes are defined as “a tropical cyclone with sustained low-level winds of 74 miles per hour or great” (CSU, 2008). The Atlantic Basin consists of the areas of the North Atlantic Ocean, Caribbean Sea and Gulf of Mexico.

Hurricane Season

The hurricane season officially runs June 1st through November 30. Although occasional storms form before or after these dates, the majority of storms occur within the given dates.