The 2017 Atlantic hurricane season was the second most active hurricane season on record, behind only 2005, due to the presence of a moderate La Niña. The season featured 23 depressions, 21 of which became named storms (tropical storm or higher). 10 became hurricanes, and 5 became major hurricanes (category 3 or higher). The season officially began on June 1 and ended on November 30, dates which conventionally delimit the period during each year in which most tropical cyclones develop in the Atlantic Ocean. However, storms can form out of the conventionally delimited seasonal bounds, as demonstrated by Tropical Storm Arlene, which developed one month before the official beginning of the season, and became the earliest storm on record to make landfall in the United States. The active season