The 2013 Atlantic hurricane season is gearing up to be an extremely active one according to NOAA’s Atlantic Hurricane Season Outlook, which was released yesterday. The outlook, issued by NOAA’s Climate Prediction Center, states that there is a 70% chance of there being 13 to 20 named storms this year. Out of these, 7 to 11 will likely become hurricanes, of which 3 to 6 will likely be major hurricanes. By “major hurricanes” the report means Category 3, 4 or 5 storms — winds of 111 mph or more.
The six-month hurricane season “officially” begins on June 1, though of course, storms follow their “rules”, not human-created ones. The numbers in the 2013 outlook are significantly higher than the seasonal average — 12 named storms, 6 hurricanes and 3 major hurricanes. The prospect of another major storm, such as Hurricane Sandy, striking the US is likely in the back of many people’s minds, especially considering that not much has really been done to improve coastal resiliency since that storm.
“With the devastation of Sandy fresh in our minds, and another active season predicted, everyone at NOAA is committed to providing life-saving forecasts in the face of these storms and ensuring that Americans are prepared and ready ahead of time.” said Kathryn Sullivan, Ph.D., NOAA acting administrator. “As we saw first-hand with Sandy, it’s important to remember that tropical storm and hurricane impacts are not limited to the coastline. Strong winds, torrential rain, flooding, and tornadoes often threaten inland areas far from where the storm first makes landfall.”
Larger, and more intense, storms are predicted to occur with increasing frequency in the coming years as result of climate change. Such storms can be devastating on their own, but when you factor in the other associated effects of global climate change, such storms are likely to have a truly profound effect on many people’s lives in the future.
With regards to the 2013 hurricane outlook, the primary cause of the extremely active season is the convergence of three separate “climate factors”.
These factors are:
– “A continuation of the atmospheric climate pattern, which includes a strong west African monsoon, that is responsible for the ongoing era of high activity for Atlantic hurricanes that began in 1995.”
– “Warmer-than-average water temperatures in the tropical Atlantic Ocean and Caribbean Sea.”
– “El Niño is not expected to develop and suppress hurricane formation.”
“This year, oceanic and atmospheric conditions in the Atlantic basin are expected to produce more and stronger hurricanes,” said Gerry Bell, Ph.D., lead seasonal hurricane forecaster with NOAA’s Climate Prediction Center. “These conditions include weaker wind shear, warmer Atlantic waters and conducive winds patterns coming from Africa.”
Something to keep in mind — NOAA’s seasonal hurricane outlook doesn’t predict how many hurricanes will make landfall, simply how many will form. Those predictions can’t be made until the weather patterns that cause hurricane formation are already in action. Such forecasts, for all of the individual storms, will be provided throughout the season by NOAA’s National Hurricane Center.
“New for this hurricane season are improvements to forecast models, data gathering, and the National Hurricane Center communication procedure for post-tropical cyclones. In July, NOAA plans to bring online a new supercomputer that will run an upgraded Hurricane Weather Research and Forecasting (HWRF) model that provides significantly enhanced depiction of storm structure and improved storm intensity forecast guidance.”
“Also this year, Doppler radar data will be transmitted in real time from NOAA’s Hurricane Hunter aircraft. This will help forecasters better analyze rapidly evolving storm conditions, and these data could further improve the HWRF model forecasts by 10% to 15%.”
“The National Weather Service has also made changes to allow for hurricane warnings to remain in effect, or to be newly issued, for storms like Sandy that have become post-tropical. This flexibility allows forecasters to provide a continuous flow of forecast and warning information for evolving or continuing threats.”