Hurricane Season Begins

It's June 1 and it's that time of the year again. Yes, today marks the beginning of hurricane season in the Atlantic Ocean and will run until November 30. It's already been active prior to the official start with a tropical depression and strong unnamed system both affecting the Gulf Coast. However, official hurricane forecasts from Colorado State University and NOAA both expect a near average year for tropical cyclone activity in the Atlantic basin. Colorado State is forecasting 12 named storms, 6 hurricanes, and 2 major hurricanes. NOAA, on the other hand, is forecasting 9-14 named storms, 4-7 hurricanes, and 1-3 major hurricanes. The average season consists of 9.6 named storms, 5.9 hurricanes, and 2.3 major hurricanes.

Both forecasts suggest that there may be slightly higher than normal activity for named storms, but hurricane and major hurricane activity should be near normal. A developing but weak El Nino episode (check back soon for a future discussion on this) is cited as the main reason for an average year. Since El Nino has not truly developed yet, it's possible that the early part of the season could be more active than normal. This seems to be a common theme during years where ENSO-neutral conditions are present at the beginning of the season.

In fact, it appears that the middle to end of June could see an upswing in tropical cyclone activity as a Madden-Julian Oscillation pulse moves into the Caribbean. In the middle and later parts of the season, El Nino should be developed to the point that stronger than normal westerly upper level winds will be located across the Atlantic basin. This will enhance vertical wind shear, which will act to rip apart most easterly tropical waves. The tropical systems most likely to cause headaches for the U.S. in the middle to later part of the season are home brew storms that initiate from stalled frontal boundaries or upper level disturbances. Like my buddy Greg Nordstrom always says, it only takes one storm to make an unforgettable season. Most everyone will remember the 1992 hurricane season for Hurricane Andrew, but do you remember how many named storms there were that season? Only six. That's not to say that another Andrew will occur this year, but the point is that only one storm can make a season.