The 2005 hurricane season ended months ago, but it still added a storm for the record books last week when a short-lived subtropical storm near the Azores Islands was identified during a routine post-season review.
The unnamed storm raised the number of tropical/subtropical systems in the Atlantic Basin during the 2005 season to 28, further adding to the already record-breaking year.
The old record had been 21 storms, set in 1933.
The Tropical Prediction Center/National Hurricane Center in Miami announced the storm on 10 April, saying that on rare occasions it identifies a previously unnoted tropical or subtropical storm from new data or meteorological interpretation.
The unnamed storm began as an upper-level low just west of the Canary Islands on 28 September, moved westward, then west-north-westward before eventually turning north-eastward.
It developed into a subtropical depression on 4 October, and its wind speed increased to 45 knots – or tropical/subtropical storm strength – later that day as it passed the Azores Islands west of Portugal.
The TPC/NHC found several pieces of evidence to suggest the system had enough tropical characteristics to be considered a subtropical storm rather than a non-tropical low.
The unnamed storm merged with a cold front on 5 October, and later that day the remains of the subtropical storm were absorbed by a non-tropical low that evolved into Hurricane Vince a few days later.