Based on numbers of expected storms, hurricanes and major hurricanes and not factoring in potential impact to land, 2012 is expected to be less active than last year.
There are a couple of factors that have led the AccuWeather.com Long-Range Forecasting Team to forecast lower numbers of named storms this year.
Starting Out with Less-Favorable Conditions
Compared to 2011, this Atlantic Hurricane Season will start out with a less-conducive environment for tropical storms to develop. The official start of the season in the Atlantic is June 1.
Strong high-level winds are in place over the western and central Caribbean, promoting increased wind shear. If these high-level winds do not abate, increased wind shear will inhibit tropical storm development early in the season.
Strong wind shear, which is the change of wind speed or direction with altitude, causes building clouds to be tilted, restricting vertical development. Unless a tropical system has a vertically oriented core, its ability to develop are diminished.
The surface pressure across the Atlantic is not as low as it was in 2011, when there was below-normal surface pressure across the Caribbean. The surface pressure is now near to above-normal in the same region.
When surface pressure is lower, it promotes tropical storm development.
"If numbers are low early in the season, then overall numbers for the entire season will turn out lower than the forecast," AccuWeather.com Expert Senior Meteorologist Dan Kottlowski cautioned.
Transition into El NiñoA shift into an El Niño pattern is expected by the peak of the Atlantic Hurricane Season, which occurs around Sept. 11. El Niño is a phenomenon classified by above-normal water temperatures in the central and eastern equatorial Pacific Ocean. It is often associated with diminished development of tropical systems in the tropical Atlantic.
"A change to El Niño forces the westerlies to migrate farther south, causing increased [wind] shear that will diminish or perhaps shut down further development beyond September," Kottlowski said.
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A surge of milder air will bring the warmest air since mid-November to the United Kingdom this week.
Dry weather will prevail much of the week across Germany as the recent chill eases.
The storm system that drenched the south-central U.S. since this past weekend will soak the Southeastern and mid-Atlantic states on Tuesday.
A blast of arctic air will create wintry travel in the Upper Midwest and part of the Northeast later this week.
On the heels of Cyclone Nada, a more significant tropical cyclone threatens to take aim at India this week.
The storm that recently brought the first snow of the season to coastal areas of the northwestern U.S. will target the interior West into midweek.
Before the coldest air so far this season arrives, parts of the northeastern United States will face slow and slick travel early this week.
The threat for flash flooding and localized severe thunderstorms, including isolated tornadoes, will expand across the southern United States early this week.