2009 Atlantic tropical wrap-up

The hurricane season in the Atlantic basin this year has been the mildest since 1997. The first named storm did not form until the second week of August. A tropical depression did form at the end of May but never developed into an organized storm.

A total of 9 named storms formed throughout the year. The first 6 storms, Tropical Storm Ana through Hurricane Fred, formed during the month from August 11 through September 12.

A second depression that did not develop formed at the end of September followed by Grace and Henri in early October. A full month passed by before Ida formed in early November. It is possible that another storm could form, even after November 30th, but it is highly unlikely this year. El Nino has generated conditions unfavorable for cyclone development. The primary effect of El Nino in the Atlantic has been an increase in shearing winds that disrupt the formation of tropical disturbances into full blown storms.

2009 Hurricane Season Quietest in Decades (National Geographic)

As the 2009 Atlantic hurricane season comes to an end November 30, it will be remembered as one of the quietest in almost two decades, meteorologists say.

That's because persistent, upper-level winds linked to El Niño—unusually warm waters that sometimes form off the northwestern coast of South America—hampered tropical storm formation. Just 9 storms took shape, instead of an average of 15.

During El Niño, the winds—known as the jet stream—shift southward and disrupt hurricane formation and development in the Atlantic Basin, which includes the Caribbean Sea and the Gulf of Mexico.

Of the storms that did form, only four affected the US coast at all.

• Hurricane Bill had a long run along the east coast of the US and Canada producing very high surf that closed beaches and even resulted in one death.
• Danny threatened the Carolina coasts with waves and rain but broke up before making landfall.
• The two storms that did make landfall in the US were Claudette on the Florida panhandle and Ida on the Alabama Gulf Coast.
• Ana and Erika also affected land crossing islands in the Caribbean before dissipating.

Finally, an unusual storm to form was Tropical Storm Grace which formed the furthest north for a tropical storm that didn't start as a subtropical storm. Grace maintained her tropical charachteristics for quite a while before finally becoming extra tropical just prior to making landfall in Ireland.

2009 Atlantic Basin Tropical Summary (The Weather Channel)

Only Tropical Storms Claudette and Ida made landfall in the U.S. thus far (1 in the Florida Panhandle and the other in southern Alabama near the Florida border). There have been no U.S. hurricane strikes. 8 of the 11 tropical cyclones lasted less than four days and 5 of these lasted two days or less. Only Ana and Bill lasted more than 5 days; Bill being the only true "long-track" Atlantic hurricane of 2009 lasted about 9 days.

Tropical storm Grace formed in the NE Atlantic and goes into the record books as the farthest north tropical storm formation (without first being a subtropical storm). From the track map below it is obvious all named storms, except Claudette, have thus far formed in the Atlantic. Only Anna and Erika have briefly entered the NE Caribbean Sea. So based on tropical storm duration and track behavior it was a very quiet hurricane season for most land areas, including the U.S. This was the quietest hurricane season since 1997 (7 named storms and 3 hurricanes) and the second quietest in the 1995 to 2009 "active era" in terms of storms and hurricanes. The last time there were only 2 hurricanes was back in 1992. There remains a small portion of hurricane season yet to come, so we say always be prepared just in case.

Graphic courtesy of The Weather Channel