The 2011 Atlantic hurricane season will be nearly as busy as the one that just ended, Colorado State University meteorologists predicted on Wednesday.

Forecast Parameter and 1950-2000  

Climatology (in parentheses)

8 December 2010

Forecast for 2011

Named Storms (NS) (9.6) 17
Named Storm Days (NSD) (49.1)


Hurricanes (H) (5.9)


Hurricane Days (HD) (24.5)


Major Hurricanes (MH) (2.3)


Major Hurricane Days (MHD) (5.0)


Accumulated Cyclone Energy (ACE) (96.1)


Net Tropical Cyclone Activity (NTC) (100%)



The forecasting team anticipates 17 tropical storms, with nine of those strengthening into hurricanes during the season that runs from June 1 to November 30.

Five will grow into “major” hurricanes of category 3 or higher on the five-step Saffir-Simpson scale of hurricane intensity, with sustained winds of at least 111 mph (178 km per hour), the team predicted.

That compares with 19 tropical storms, 12 hurricanes and five major hurricanes during the 2010 season that just ended on November 30. The 2020 season tied with 1887 and 1995 for the third-highest storm total on record.

An average season brings 11 storms, six hurricanes and two major hurricanes in the Atlantic, Caribbean and Gulf of Mexico.

The forecasters said sea surface temperatures in the North Atlantic were still at record warm levels, indicating the region is still in a multi-decade period of high activity for hurricanes.  It also seemed unlikely that El Nino would develop. El Nino is a warming of the tropical Pacific that produces wind patterns that squelch development of tropical storms in the Atlantic.

There is a great deal of uncertainty in forecasts issued so far in advance but meteorologists have become more effective at analyzing large-scale patterns and predicting whether the next season will be busy, average or calmer than average.  This gives those of us in the field of emergency management just a bit of a heads up!