NOAA Predicts Above Normal Hurricane Season

NOAA National Weather Service forecasters at the Climate Prediction Center predict above normal hurricane activity in the Atlantic basin this year.

NOAA’s outlook for the 2024 Atlantic hurricane season, which spans from June 1 to November 30, predicts an 85% chance of an above-normal season, a 10% chance of a near-normal season and a 5% chance of a below normal season.

NOAA is forecasting a range of 17 to 25 total named storms (winds of 39 mph or higher). Of those, eight to 13 are forecast to become hurricanes (winds of 74 mph or higher), including four to 7 major hurricanes (category 3, 4 or 5; with winds of 111 mph or higher). Forecasters have a 70% confidence in these ranges.

The upcoming Atlantic hurricane season is expected to have above-normal activity due to a confluence of factors, including near-record warm ocean temperatures in the Atlantic Ocean, development of La Nina conditions in the Pacific, reduced Atlantic trade winds and less wind shear, all of which tend to favor tropical storm formation.

As one of the strongest El Ninos ever observed nears its end, NOAA scientists predict a quick transition to La Nina conditions, which are conducive to Atlantic hurricane activity because La Nina tends to lessen wind shear in the tropics. At the same time, abundant oceanic heat content in the tropical Atlantic Ocean and Caribbean Sea creates more energy to fuel storm development.

This hurricane season also features the potential for an above-normal West African monsoon, which can produce African easterly waves that seed some of the strongest and longer-lived Atlantic storms. Finally, light trade winds allow hurricanes to grow without disrupting strong wind shear and minimize ocean cooling. Human-caused climate change is warming our ocean globally and in the Atlantic basin, and melting ice on land, leading to sea level rise, which increases the risk of storm surge. The rise in sea level represents a clear human influence on the damage potential from a given hurricane.

Enhanced communications in store for 2024 season NOAA will implement improvements to its forecast communications, decision support, and storm recovery efforts this season. These include:

• The National Hurricane Center (NHC) will expand its offering of Spanish language text products to include all Public Advisories, the Tropical Cyclone Discussion, the Tropical Cyclone Update, and Key Messages in the Atlantic basin.
• Beginning on or around August 15, NHC will start to issue an experimental version of the forecast cone graphic that includes a depiction of inland tropical storm and hurricane watches and warnings in effect for the continental U.S. Research indicates that the addition of inland watches and warnings to the cone graphic will help communicate inland hazards during tropical cyclone events without over-complicating the current version of the graphic.
• This season, the NHC will be able to issue U.S. tropical cyclone watches and warnings with regular or intermediate public advisories. This means that if updates to watches and warnings for storm surge or winds are needed, the NHC will be able to notify the public in an intermediate advisory instead of having to wait for the next full advisory issued every six hours.

New tools for hurricane analysis and forecasting this year:

• Two new forecast models developed by NOAA researchers will go into operation this season: The Modular Ocean Model or MOM6 will be added to the Hurricane Analysis and Forecast System to improve the representation of the key role the ocean plays in driving hurricane intensity. Another model, SDCON, will predict the probability of tropical cyclone rapid intensification.
• NOAA’s new generation of Flood Inundation Mapping, made possible through President Biden’s Bipartisan Infrastructure Law, will provide information to emergency and water managers to prepare and respond to potential flooding and help local officials better prepare to protect people and infrastructure.
• NOAA’s Weather Prediction Center, in partnership with the NHC, will issue an experimental rainfall graphic for the Caribbean and Central America during the 2024 hurricane season. This graphic provides forecast rainfall totals associated with a tropical cyclone or disturbance for a specified time.

NOAA’s outlook is for overall seasonal activity and is not a landfall forecast. In addition to the Atlantic seasonal outlook, NOAA also issues seasonal hurricane outlooks for the eastern Pacific, central Pacific and western north Pacific hurricane basins. NOAA’s Climate Prediction Center will update the 2024 Atlantic seasonal outlook in early August, prior to the historical peak of the season.