Eric Blake, a hurricane specialist at the National Hurricane Center (NHC), commented on the lack of hurricanes west of 55 degrees longitude in the Atlantic basin so far this season. Blake said this marks the first time there have been no western Atlantic hurricanes through Sept. 22 since 1914, when there weren't any.
The 1914 season was the last time no hurricanes formed anywhere in the Atlantic basin, which includes the Caribbean Sea and Gulf of Mexico.
Lack of Moisture
A graphic showing precipitable water, or a measure of moisture in a column of the atmosphere, anomalies this Atlantic tropical season. There has been a notable lack of moisture from the Gulf of Mexico into the Caribbean.
Two factors working against hurricane development, wind shear and dry air, have been quite prevalent from the Gulf of Mexico into much of the Caribbean all summer long.
Hurricanes thrive off of rich, tropical moisture evaporating into the air from warm ocean water. Dry air is detrimental to hurricane formation because it disrupts the cycle of warm moist air rising to form clouds and thunderstorms – a cycle that essentially gives a hurricane its source of energy.
Likewise, wind shear, or the change of wind direction and speed with height, creates a hostile environment for tropical systems, as it too disrupts the ability of clouds and thunderstorms to organize in a way that supports the formation or continuation of a hurricane.
El Niño can be partially to blame. This setup features warming of the Pacific Ocean and is generally associated with unfavorable wind patterns across the western Atlantic.
http://www.weather.com/storms/hurricane/news/no-hurricanes-western-atlantic-2015
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