2005 Azores Subtropical Storm

The 2005 Azores subtropical storm was the nineteenth nameable storm of the record-breaking 2005 Atlantic hurricane season. It was not officially named by the National Hurricane Center as it was operationally classified as a non-tropical low. The storm developed in the eastern Atlantic Ocean out of a low-pressure area that gained subtropical characteristics on October 4. The storm was short-lived, crossing over the Azores later on October 4 before becoming extratropical again on October 5. No damage or fatalities were reported. After being absorbed into a cold front, the system went on to become Hurricane Vince, which affected the Iberian Peninsula.

Months after the hurricane season, when the National Hurricane Center was performing its annual review of the season and its named storms, forecasters Jack Beven and Eric Blake identified this previously unnoticed subtropical storm. Despite its unusual location and wide wind field, the system had a well-defined center convecting around a warm core—the hallmark of a subtropical storm.