The last hurricane season in the Atlantic was anemic, being one of least active periods on record. This was attributed to extra dust blown off the Sahara which inhibits hurricane development.
Right now, the various forecasting agencies around the world are agreeing that there is a greater than 50% chance, perhaps a 70% chance of an El Nino event happening this year, starting in the Summer or Fall. Traditionally, we think of El Nino events as inhibiting tropical storm and hurricane formation in the Atlantic. Today, a group that predicts hurricane activity in the Atlantic every year has used the likely El Nino event to predict that this year’s season will be relatively low level.
According to this prediction, there will be nine named storms in the Atlantic, three of which will become hurricanes, one of those a major hurricane (Category 3 or above), with a 35% chance of a major hurricane hitting the US coast somewhere.
Personally, I’m not sure about the effects of El Nino, should it occur. There haven’t been that many El Ninos during the period for which there are high quality records. This year’s El Nino, if it materializes, will occur during a period when we are experiencing strange and different things in the Arctic. Many of the teleconnections between El Nino and other conditions elsewhere in the world are highly variable and many are not all that well understood. Overall, with global warming, conditions may simply be different enough this year from any other prior year that predictions may be off. While it makes sense that if there is an El Nino we should expect an attenuated Atlantic hurricane season, I’m not going to be surprised if several of the usual links between El Nino and various weather conditions are different than “usual.”