NOAA confirms average hurricane season ahead

(CNS): Just one week ahead of the official start of the hurricane season experts from the US are calling for nine to 15 tropical storms four to eight of which will become hurricanes in its 2012 long term Atlantic forecast. The National Oceanic and Atmospheric Administration is expecting what it described as a "near normal" season with one to three major hurricanes of Category 3 or higher intensity on the Saffir-Simpson scale. Hurricane season for the Atlantic Ocean, Caribbean Sea and Gulf of Mexico officially runs from June 1 to November 30, but tropical Storm Alberto came well ahead of time and on Friday morning the NHC was giving a broad area of low pressure near the north-western Bahamas a 70 percent chance of becoming a tropical storm this weekend.

Pre-season storms are not uncommon and experts say there is not necessarily a connection between an early start and a busy season. For the entire six-month season, NOAA’s Climate Prediction Center said there was a 70 percent chance of nine to 15 named storms. Forecasters said that a near normal or average season brings 12 tropical storms with six hurricanes. Experts say the region is still in the midst of a multi-decade active period for hurricanes that began in 1995 but temperatures in the eastern Atlantic are cooler this year and the strong wind shear will combine to keep limit storm numbers. El Nino, which is warming the tropical Pacific could also "kill off" Atlantic hurricanes, forecasters said.

“NOAA’s outlook predicts a less active season compared to recent years,” said NOAA Administrator Jane Lubchenco, Ph.D. “But regardless of the outlook, it’s vital for anyone living or vacationing in hurricane-prone locations to be prepared.”
Although Improvements in monitoring and predicting hurricanes have been remarkable over the last two decades Lubchenco said more work remains to be done to unlock the secrets of hurricanes, especially in the area of rapid intensification and weakening of storms.

“We're stepping up to meet this challenge through our Hurricane Forecast Improvement Project, which has already demonstrated exciting early progress toward improving storm intensity forecasts," she said.

This season NOAA is introducing enhancements to two of the computer models available to hurricane forecasters – the Hurricane Weather Research and Forecasting (HWRF) and the Geophysical Fluid Dynamics Laboratory (GFDL) models. The HWRF model has been upgraded with a higher resolution and improved atmospheric physics. This latest version has demonstrated a 20 to 25 percent improvement in track forecasts and a 15 percent improvement in intensity forecasts relative to the previous version while also showing improvement in the representation of storm structure and size. Improvements to the GFDL model for 2012 include physics upgrades that are expected to reduce or eliminate a high bias in the model's intensity forecasts.

The seasonal outlook does not predict how many storms will hit land. Forecasts for individual storms and their impacts are provided by NOAA’s National Hurricane Center, which continuously monitors the tropics for storm development and tracking throughout the season using an array of tools including satellites, advance computer modeling, hurricane hunter aircraft, and land- and ocean-based observations sources such as radars and buoys.