Activity is tracked in terms of https://en.wikipedia.org/wiki/Accumulated_cyclone_energy. This Wikipedia page has a list of previous North Atlantic hurricane seasons by ACE.

If the value is 10 or more ACE away from one of the cutoff values, this market resolves in January 2025 to whatever value is listed on Wikipedia. If it is close to a cutoff, the market resolves after the reanalysis of all storms is completed (usually in April) to account for postseason adjustments in ACE.

North Atlantic sea surface temperature anomalies, which are correlated with tropical cyclone activity, are currently (as of February 20) extremely high and can be tracked here: https://www.tropicaltidbits.com/analysis/ocean/cdas-sflux_ssta_atl_1.png

The last ten years had the following activity:
Below normal: 2014, 2015
Near normal: 2022
Above normal: 2016, 2018, 2019, 2021, 2023
Hyperactive: 2017, 2020

The least active season in recorded history was 1914, while the most active season was 1933.

See also my El Nino / La Nina market for hurricane season: https://manifold.markets/SaviorofPlant/will-it-be-el-nino-la-nina-or-neith. El Niño tends to suppress Atlantic tropical cyclone activity, while La Niña tends to enhance it.