Based on current la Nina conditions that are expected to transition to near-neutral conditions during the heart of the hurricane season, the Colorado State University (CSU) hurricane forecast team is calling for an active season.

The CSU team calls for 16 named storms forming in the Atlantic basin between June 1 and Nov. 30. Nine of those are expected to turn into hurricanes with five developing into major hurricanes with sustained winds of 111 mph or greater.

“We remain – since 1995 – in a favorable multi-decadal period for enhanced Atlantic Basin hurricane activity, which is expected to continue for the next 10-15 years or so,” says forecaster William Gray. “Except for the very destructive hurricane seasons of 2004-2005, U.S. coastal residents have experienced no other major landfalling hurricanes since 1999. This recent nine of 11-year period without any major landfall events should not be expected to continue.”

The team predicts that tropical cyclone activity in 2011 will be approximately 175% of the average season. By comparison, 2010 witnessed tropical cyclone activity that was 196% of the average season.

The hurricane forecast team's probabilities for a major hurricane making landfall on U.S. soil:

  • A 72% chance that at least one major hurricane will make landfall on the U.S. coastline in 2011 (the long-term average probability is 52%).
  • A 48% chance that a major hurricane will make landfall on the U.S. East Coast, including the Florida Peninsula (the long-term average is 31%).
  • A 47% chance that a major hurricane will make landfall on the Gulf Coast from the Florida Panhandle west to Brownsville (the long-term average is 30%).
  • The team also predicts a 61% chance of a major hurricane tracking into the Caribbean (the long-term average is 42%).
Probabilities of tropical storm-force, hurricane-force and major hurricane-force winds occurring at specific locations along the U.S. East and Gulf Coasts are listed on the forecast team's Landfall Probability website at www.e-transit.org/hurricane.