Six consecutive two-week forecasts were issued during the peak months of the Atlantic hurricane season from August-October. These forecasts were based on current hurricane activity, predicted activity by global forecast models and the phase of the Madden-Julian Oscillation (MJO). These two-week forecasts generally verified well.

 Integrated measures such as Net Tropical Cyclone (NTC) activity and Accumulated Cyclone Energy (ACE) were at top ten levels based on Atlantic hurricane data going back to the mid-19th century. Well above-average sea surface temperatures and reduced levels of vertical wind shear in the tropical Atlantic were two of the primary reasons why such an active season was observed.

While the season was very active, it will be most remembered for several hurricanes that devastated portions of the continental United States as well as islands in the Caribbean and other parts of the tropical Atlantic. Hurricane Harvey brought epic flooding to the Houston metropolitan area, while Irma and Maria both brought devastation to islands throughout the Caribbean and tropical Atlantic. Irma also made landfall in the Florida Keys as a Category 4, pummeling the Keys and bringing considerable damage to mainland Florida as well. The 2017 Atlantic hurricane season was also the first season on record (since 1851) to have two Category 4 hurricanes make continental United States landfall in the same year (Harvey and Irma).

(Credit: Colorado State University)