Throughout the year, Tropical Storm Risk (TSR) predicted that the 2024 North Atlantic hurricane season (June – December) would be “hyperactive” with a forecast ACE index well over 200 – which would have made for one of the most active seasons on record. Despite the season finishing as hyperactive, an unusual mid-season lull meant that the total activity fell short of predictions.
Key Events of the 2024 North Atlantic Hurricane Season:
- 18 tropical storms, 11 hurricanes, and 5 intense hurricanes and an ACE index of 162 ranked 2024 within the top 25% of active seasons since 1950.
- The early April 2024 forecast predicted 23 tropical storms, 11 hurricanes, and 5 intense hurricanes, which was very close to what was observed.
- Hurricane Beryl became the strongest June hurricane on record and devastated multiple regions, including the Grenadines, Jamaica and Texas. Beryl was the strongest hurricane to have made landfall in the Grenadines on record.
- Hurricane Helene made history as the strongest storm to hit Florida’s Big Bend and the second deadliest U.S. landfalling storm on record (behind Katrina, 2005), causing over 200 fatalities, primarily due to inland flooding.
- Hurricane Milton rapidly intensified into a Category 5 storm with winds of 155 knots and a central pressure of 897 mb—the lowest in the Gulf of Mexico since Hurricane Wilma in 2005.
The season saw six rapidly intensifying storms, a record for the Atlantic, but was marked by a surprising lull from mid-July to mid-September despite favourable large-scale conditions. This anomaly highlighted challenges in seasonal forecasting where intra-seasonal variability can have a large influence on activity.
While TSR and other agencies accurately predicted hurricane numbers, the ACE index was overestimated. The very high ACE forecasts were based on very warm sea surface temperatures across the tropical Atlantic and expectations of a developing La Niña; the latter ultimately failed to materialise.
Read TSR’s 2024 report on Atlantic seasonal forecast verification.
Looking ahead, TSR’s extended range forecast for 2025 will be updated in April. Early signals are hinting at seasonal activity close to the 30-year average (1991 – 2020).
TSR’s Atlantic seaonal forecast timeline begins with an extended range forecast in early December, followed by updates in early April, late May, early July, and early August. By mid-December, TSR publishes an end-of-season summary, verifying its forecasts against observations.