[xml][/xml]
The Bahamas Weekly Facebook The Bahamas Weekly Twitter
Bahamas Weather Last Updated: Feb 13, 2017 - 1:45:37 AM


2015 NOAA Hurricane Season Outlook
By Wayne Neely, Bahamas Meteorology Deparment
May 29, 2015 - 12:46:51 AM

Email this article
 Mobile friendly page
2015_NOAA_Hurricane_Season.jpg

NOAA (National Oceanic Atmospheric Administration) has finally released their 2015 North Atlantic Hurricane Season Outlook: NOAA is predicting 6 to 11 named storms (winds of 39 mph or higher) in the North Atlantic, of which 3 to 6 could become hurricanes, including 0 to 2 major hurricanes...NOAA is predicting that along the North Atlantic, there will be a 70 percent likelihood of six to 11 named storms (winds of 39 mph or higher), of which between three and six could become hurricanes (winds of 74 mph or higher). At most, two of those are expected to become major hurricanes, defined as Category 3, 4 or 5, characterized by winds of 111 mph or higher. Like the other governing bodies hurricane season outlooks, they are also going for a below average season. This outlook is forecast to be dominated by effects of the strengthening El Niño conditions.

"The main factor expected to suppress the hurricane season this year is El Niño, which is already affecting wind and pressure patterns, and is forecast to last through the hurricane season," said Gerry Bell, Ph.D., lead seasonal hurricane forecaster with NOAA's Climate Prediction Center. "El Niño may also intensify as the season progresses, and is expected to have its greatest influence during the peak months of the season. We also expect sea surface temperatures in the tropical Atlantic to be close to normal, whereas warmer waters would have supported storm development."
The hurricane impacts of El Niño and its counterpart La Niña are like a see-saw between the Pacific and Atlantic oceans, strengthening hurricane activity in one region while weakening it in the other. El Niño is a cyclic climate phenomenon that involves both the ocean and the atmosphere. One of its hallmarks is warmer-than-average sea-surface temperatures in the tropical Pacific Ocean. Although the El Niño fizzled last winter, the pool of warm water stuck around this spring and strengthened into a full-blown event. In El Niño years, the wind patterns are aligned in such a way that the vertical wind shear is increased over the Caribbean and Atlantic. The increased wind shear helps to prevent tropical disturbances from developing into hurricanes. whereas, the opposite applies in the eastern Pacific, the wind patterns are altered in such a way to reduce the wind shear in the atmosphere, contributing to more storms.

From experience when many Bahamians hear 'below average season' they tend to let their guards down because they think 'below average' means no hurricanes this year for them and tend to prepare less. Keep in mind that While a below-normal season is likely in Atlantic, there is still a 10 percent chance of an above-normal season.

A below-normal season doesn't mean we're off the hook or we will be spared. As we've seen before, below-normal seasons can still produce catastrophic impacts to The Bahamas. Sadly, one notable example of this was the 1992 season in which only seven named storms formed, yet the first was Andrew - a very powerful Category 5 Major Hurricane that devastated The Bahamas and left a staggering $250 million dollars in damage to The Bahamas alone and over $26.5 Billion in the state of Florida. It's been 10 and 11 years respectively since the historic 2004 and 2005 hurricane seasons, when three hurricanes Frances, Jeanne and Wilma devastated the island of Grand Bahama, leaving millions of dollars in damage and the economy of Grand Bahama in disarray. It is fair to say that even to this day, the economy of Grand Bahama has still not fully recovered from those hurricanes.

This season's first storm, Tropical Storm Ana which formed on May 8 and came ashore in the Carolinas earlier this month, bringing rain from Virginia to South Carolina. It did not cause any major problems.

Why we forecast a below average 2015 North Atlantic hurricane season:

The forecasters cited the following main factors that will influence the coming season:

1) The current borderline weak/moderate El Niño event is expected to persist or intensify during the 2015 hurricane season. El Niño events tend to suppress Atlantic hurricane activity in three ways:
- By creating high levels of wind shear over the tropical Atlantic, which tends to tear storms apart.
- By increasing sinking motion and high pressure over the tropical Atlantic.
- By making the air more stable over the tropical Atlantic.

2) Near-average sea surface temperatures (SSTs) are in place over the hurricane Main Development Region (MDR), from the Caribbean to the coast of Africa between between 10°N and 20°N. These SSTs are expected to be near or below average during the peak August - October portion of hurricane season, and are expected to be cooler than SSTs in the remainder of the global tropics (SSTs in the remainder of the global tropics were 0.31°C warmer than SSTs in the MDR in May.) This configuration of SSTs is often quite hostile to Atlantic tropical cyclone development.

3) The active period of hurricane activity that began in 1995 due to a natural decades-long cycle in hurricane activity called the Atlantic Multi-decadal Oscillation (AMO) may now be over. The SST pattern associated with that cycle is absent this year, and NOAA said: "There have been two seasons in a row, 2013 and 2014, with below-normal and near-normal activity respectively and neither had an El Niño event responsible for the reduced activity. The current configuration of SSTs in the Atlantic Ocean, both in the MDR and the entire North Atlantic, are suggestive that the AMO may no longer be in the warm phase."


Bookmark and Share




© Copyright 2015 by thebahamasweekly.com

Top of Page

Receive our Top Stories



Preview | Powered by CommandBlast

Bahamas Weather
Latest Headlines
Inclement and a very wet weather ahead for the week for The Bahamas
Severe Thunderstorm warning - November 5th
Severe Weather Warning- Oct. 22
6am News Item on Tropical Storm Nicholas
Alert #21 on Tropical Depression Fred