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NOAA’s updated 2012 Atlantic Hurricane Season Outlook indicates a high likelihood (85% chance) of a near- or above-normal season. The outlook calls for a 50% chance of a near-normal season, a 35% chance of an above normal season, and only a 15% chance of a below-normal season. See NOAA definitions of above-, near-, and below-normal seasons. The Atlantic hurricane region includes the North Atlantic Ocean, the Caribbean Sea, and the Gulf of Mexico. 

All indications are that the 2012 Atlantic hurricane season will reflect competing factors, some supporting stronger hurricane activity and some likely suppressing hurricane activity later in the season. 

Favoring more activity are very conducive conditions now in place, which are linked to the ongoing the tropical multi-decadal signal. This climate pattern has been associated with increased Atlantic hurricane activity since 1995. It is linked to above-average sea surface temperatures (SSTs) across the tropical Atlantic Ocean and to an enhanced west African monsoon, both of which are in place as was predicted in the May pre-season outlook. 

El Niño is a competing factor that acts to suppress Atlantic hurricane activity by increasing the vertical wind shear over the tropical Atlantic. The timing of El Niño is very important to this outlook. El Niño is expected to develop during August or September, but its suppressing influence is not expected until later in the season. The possibility of near-average SSTs in the far eastern tropical Atlantic also suggests a more moderate hurricane season. 

Based on these competing factors, we estimate a 70% probability for each of the following ranges of activity for the entire 2012 Atlantic hurricane season:


12-17 Named Storms, (top winds of 39 mph or higher), including: 
5-8 Hurricanes (top winds of 74 mph or higher), of which: 
2-3 are expected to become Major Hurricanes (Cat. 3-5, wind speeds at least 111 mph). 
An Accumulated Cyclone Energy (ACE) range of 75%-135% of the median. 

The seasonal activity is expected to fall within these ranges in 70% of seasons with similar climate conditions and uncertainties to those expected this year. These ranges do not represent the total possible ranges of activity seen in past similar years.