2015 Atlantic Hurricane Season (Shadow Jackal274's Version)

The 2015 Atlantic Hurricane Season was a near average Atlantic hurricane season that produced 11 tropical cyclones, 8 named storms, 5 named hurricanes and 2 major hurricanes. The season officially began on June 1, 2015 and ended on November 30, 2015. The first storm of the season, Ana, developed a month before the official start of the season, becoming the first pre-season tropical or subtropical cyclone since 2012's Beryl and the earliest-forming cyclone since 2003's Ana. Despite the unusually early start, an ongoing El Niño event was forecast by many organizations to limit tropical cyclone activity in the basin throughout the season. The final storm, Hanna, dissipated on October 28.

Seasonal Forecasts
Forecasts of hurricane activity are issued before each hurricane season by noted hurricane experts Philip J. Klotzbach, William M. Gray, and their associates at Colorado State University (CSU); and separately by National Oceanic and Atmospheric Administration (NOAA) forecasters.

Klotzbach's team (formerly led by Gray) defined the average number of storms per season (1981 to 2010) as 12.1 tropical storms, 6.4 hurricanes, 2.7 major hurricanes (storms reaching at least Category 3 strength on the Saffir–Simpson hurricane wind scale), and an Accumulated Cyclone Energy (ACE) index of 96.1. NOAA defines a season as above-normal, near-normal or below-normal by a combination of the number of named storms, the number reaching hurricane strength, the number reaching major hurricane strength, and the ACE index.

Pre-Season Forecasts

On December 9, 2014, Tropical Storm Risk (TSR), a public consortium consisting of experts on insurance, risk management, and seasonal climate forecasting at University College London, issued its first outlook on seasonal hurricane activity during the 2015 season. In its report, the organization forecast activity about 20% below the 1950–2014 average, or about 30% below the 2005–2014 average, totaling to 13 (±4) tropical storms, 6 (±3) hurricanes, 2 (±2) major hurricanes, and a cumulative ACE index of 79 (±58) units. This forecast was largely based on an enhancement of low-level trade winds across the tropical Atlantic during the July to September period. TSR's report stressed that uncertainty in this forecast existed due to the unpredictability in the El Niño Southern Oscillation and North Atlantic sea surface temperatures. A few months later, on April 9, 2015, the organization updated its report, detailing its prediction of activity 45% below the 1950–2014 average, or about 50% below the recent 2005–2014 average, with 11 named storms, 5 hurricanes, 2 major hurricanes, and a cumulative ACE index of 56 units. TSR cited what were expected to be cooler than average ocean temperatures across the tropical North Atlantic and Caribbean Sea as reasoning for lower activity. In addition, the report stated that if the ACE forecast for 2015 were to verify, the total values during the three-year period from 2013–2015 would be the lowest since 1992–1994, signalling a possible end to the active phase of Atlantic hurricane activity that began in 1995.

On April 9, CSU also released its first quantitative forecast for the 2015 hurricane season, predicting 7 named storms, 3 hurricanes, 1 major hurricane, and a cumulative ACE index of 40 units. The combination of cooler than average waters in the tropical and subtropical Atlantic, as well as a developing El Niño predicted to reach at least moderate intensity, were expected to favor one of the least active seasons since the mid-1990s. The probabilities of a major hurricane striking various coastal areas across the Atlantic were lower than average, although CSU stressed that it only takes one landfalling hurricane to make it an active season for residents involved. On April 13, North Carolina State University (NCSU) released its forecast, predicting a near record-low season with just 4 to 6 named storms, 1 to 3 hurricanes, and 1 major hurricane.

On May 21, the United Kingdom Met Office (UKMO) issued its forecast, predicting a season with below-normal activity. It predicted 8 storms, with a 70% chance that the number of storms would be between 6 and 10; it predicted 5 hurricanes, with a 70% chance that that number would fall in the range of 3 to 7. UKMO's ACE index prediction was 74 units, with a 70% chance of the index falling in the range of 40 to 108 units. On May 27, NOAA released its seasonal forecast, predicting a below-normal season with 6 to 11 named storms, 3 to 6 hurricanes, and 0 to 2 major hurricanes. NOAA indicated that there was a 70% chance of a below-normal season, a 20% chance of a near-normal season, and a 10% chance of an above-normal season.

Mid-Season outlooks

On June 1, CSU released an updated forecast, increasing the number of predicted named storms to 8, due to the early formation of Tropical Storm Ana, while keeping the predictions for hurricanes and major hurricanes at 3 and 1, respectively; the ACE index forecast was also kept at 40 units. Probabilities of a major hurricane making landfall on various coastal areas remained below average.