The 1906 Atlantic hurricane season was an average season. It featured twelve tropical cyclones, eleven of which became storms, six became hurricanes and three became major hurricanes. The first storm of the season, a tropical storm in the northern Caribbean, formed on June 8; although it struck the United States, no major impacts were recorded. July saw a period of inactivity, with no known storms. However, in August, the streak of inactivity ended with two storms, including a powerful hurricane. September brought three storms, including a deadly hurricane, with catastrophic impacts in Pensacola and Mobile. October included three storms, with a powerful hurricane that killed over 200 people. The final storm of the season impacted Cuba in early November and dissipated on November 9. The season was quite deadly, with at least with 381 total recorded deaths. Season summary Prior to the advent of modern tropical cyclone tracking technology, notably satellite imagery, many hurricanes that did not affect land directly went unnoticed, and storms that did affect land were not recognized until their onslaught. As a result, information on older hurricane seasons was often incomplete. Modern-day efforts have been made and are still ongoing to reconstruct the tracks of known hurricanes and to identify initially undetected storms. In many cases, the only evidence that a hurricane existed was reports from ships in its path, and judging by the direction of winds experienced by ships, and their location in relation to the storm, it is possible to roughly pinpoint the storm's center of circulation for a given point in time. This is the manner in which all of the eleven known storms in the 1906 season were identified by hurricane expert José Fernández-Partagás's reanalysis of hurricane seasons between 1851 and 1910. Partagás also extended the known tracks of three other hurricanes previously identified by scholars. The information Partagás and his colleague uncovered was largely adopted by the National Oceanic and Atmospheric Administration's Atlantic hurricane reanalysis in their updates to the Atlantic hurricane database (HURDAT), with some slight adjustments. HURDAT is the official source for such hurricane data as track and intensity, although due to a sparsity of available records at the time the storms existed, listings on some storms are incomplete. The season's activity was reflected with an accumulated cyclone energy (ACE) rating of 163, the highest total since 1893. ACE is a metric used to express the energy used by