The 2023 Atlantic hurricane season could see activity levels about 15 per cent below the 30-year norm, a leading hurricane forecasting team has said.

As reported by specialist website Artemis, Tropical Storm Risk has issued an extended range forecast for the season.

TSR said: “The TSR extended range forecast for North Atlantic hurricane activity in 2023 anticipates a season with below-norm activity.

“TSR predicts North Atlantic hurricane activity in 2023 will be about 15 per cent below the 1991-2020 30-year norm and close to the long-term 1950-2022 norm.”

Artemis said this equates to a prediction for Accumulated Cyclone Energy of 104, below the 1991-2020 30-year norm of 122.

In probability terms, Artemis reported, TSR sees a 22 per cent probability of an above-normal North Atlantic ACE in 2023, a 49 per cent likelihood of a near-normal ACE, and a 30 per cent chance of a below-normal ACE season.

It said that adds up to a forecast that the season will see three intense, or major hurricanes, six hurricanes and 13 tropical storms, which it said is comparable to the 1991-2020 30-year norms of three, six and 12 respectively.

Artemis said the forecasters explained: “TSR’s forecast for below-norm activity is due to the warm-neutral or weak El Niño conditions expected through summer 2023.

“The current La Niña conditions have peaked and are expected to weaken to neutral conditions through spring 2023 and transition to borderline El Niño conditions through summer, which favours enhanced trade wind strength, reduced vorticity and higher vertical wind shear over the tropical North Atlantic and Caribbean Sea where hurricanes form.

“Despite the expectation for a below-norm hurricane season in 2023, large uncertainties remain. These include the forecast strength of El Niño Southern Oscillation, the strength and sign of the North Atlantic Oscillation through spring, and how warm the tropical Atlantic will be in August-September.

“Also variance exists in the level of hurricane activity possible from the same climate factors.”

Artemis said the commentary on the stage of the ENSO is likely to be helpful and may provide reinsurance underwriters and insurance-linked securities investors with something to think about as they plan for 2023, especially as many consider El Niño phases as more likely to suppress Atlantic hurricane activity.