The 1920 Atlantic hurricane season featured tropical storms and hurricanes only in the month of September. Although no "hurricane season" was defined at the time, the present-day delineation of such is June 1 to November 30. The first system, a hurricane, developed on September 7 while the last, a tropical depression, transitioned into an extratropical cyclone on October 27. Of note, four of the six cyclones co-existed with another tropical cyclone during the season. Of the season's six tropical cyclones, five became tropical storms and four strengthened into hurricanes. Furthermore, none of these strengthened into a major hurricane—Category 3 or higher on the modern-day Saffir–Simpson hurricane wind scale—marking the seventh such occurrence since 1900. The strongest hurricane of the season peaked as only as a strong Category 2 with winds of 110 mph (175 km/h). The second hurricane caused one death and $1.45 million (1920 USD) in damage in Louisiana, the third left one fatality in North Carolina, and the fifth storm indirectly killed one person in Florida. The season's activity was reflected with an accumulated cyclone energy (ACE) rating of 30, below the 1911–1920 average of 58.7. ACE is, broadly speaking, a measure of the power of the hurricane multiplied by the length of time it existed, so storms that last a long time, as well as particularly strong hurricanes, have high ACEs. It is only calculated for full advisories on tropical systems at or exceeding 39 mph (63 km/h), which is the threshold for tropical storm status. Timeline Systems Hurricane One The first known storm of the season was initially identified on September 7 as a 40 mph (65 km/h) tropical storm over Atlantic Ocean. Traveling towards the northwest, the storm gradually intensified, attaining hurricane-status late on September 9. The following day, a ship in the vicinity of the storm recorded a pressure of 985 mbar (hPa), the lowest pressure recorded in relation to the storm. Around 1200 UTC, the hurricane turned towards the north and intensified into a modern-day Category 2 hurricane on the Saffir–Simpson scale early on September 11. The storm continued to intensify through September 12 when it reached its peak intensity with winds of 110 mph (175 km/h). After maintaining this intensity for 18 hours, the hurricane began to weaken as it turned towards the northwest. By 0000 UTC on September 14, the storm weakened to a Category 1 hurricane. The system began to