TYPHOON

Extended Data Table 1: Multi-basin evaluation of RI cases (2024–2026)

Purpose: Demonstrate the diversity of rapid intensification events across basins, ocean environments, and intensification rates to establish a robust observational baseline.

Typhoon Year Basin Cat RI Rate RI Period Key Feature Ocean Condition

ERROL 2025 SI Cat-5 84 kt/24h 04-15 12:00 → 04-16 12:00 Rapid RI, warm ocean conditions OHC > 100 kJ/cm², low wind shear

HORACIO 2026 SI Cat-5 84 kt/24h 02-22 18:00 → 02-23 18:00 Cat-5 storm in 2026, ocean-driven RI Strong upper-ocean heat content and warm SST

MILTON 2024 AL Cat-5 82 kt/24h 10-06 21:00 → 10-07 20:00 hurricane alley effects Record-level ocean heat content across the Gulf of Mexico

YAGI 2024 WP Cat-5 75 kt/24h 09-03 21:00 → 09-04 21:00 RI drastically in South China Sea High ocean heat content over the northern after Philippine landfall wanes power South China Sea

ERIN 2025 AL Cat-5 75 kt/24h 08-15 18:00 → 08-16 18:00 Low wind shear combined with high Favorable MDR (Main Development Region) OHC and rapid translation speed conditions

RAGASA 2025 WP Cat-5 68 kt/24h 09-20 06:00 → 09-21 06:00 Strongest typhoon of 2025, extreme RI High OHC and low wind shear near the Philippines

JOHN 2024 EP Cat-3 67 kt/24h 09-23 03:00 → 09-24 03:00 Unusual coastal RI case High coastal ocean heat content and favorable conditions

KRISTY 2024 EP Cat-4 65 kt/24h 10-22 18:00 → 10-23 18:00 Low wind shear and abundant moisture Warm SST over the eastern Pacific

MAN-YI 2024 WP Cat-5 65 kt/24h 11-14 18:00 → 11-15 18:00 Sequential typhoon occurrence SST recovery after the previous typhoon

(following USAGI)

USAGI 2024 WP Cat-4 65 kt/24h 11-12 18:00 → 11-13 18:00 Consecutive occurrence with MAN-YI High SST over the western Pacific

BOLAVEN 2023 WP Cat-5 75 kt/24h 10-10 06:00 → 10-11 06:00 Intensified from Cat-1 to Cat-5 within OHC > 100 kJ/cm², low wind shear 12 hours after passing near the Mariana and strong upper-ocean heat

Islands

KONG-REY 2024 WP Cat-5 60 kt/24h 10-28 18:00 → 10-29 18:00 Presence of cold wake along storm track SST 29–30°C, high OHC near the Philippines

NEOGURI 2025 WP Cat-4 55 kt/24h 09-19 18:00 → 09-20 18:00 Developed near Wake Island, rapidly SST 29–30°C, high OHC in the North Pacific

intensified after crossing 40°N

KRATHON 2024 WP Cat-4 55 kt/24h 09-28 18:00 → 09-29 18:00 Reached Cat-4 within 2 days High OHC and low wind shear near the Philippines

HALONG 2025 WP Cat-4 49 kt/24h 10-06 18:00 → 10-07 18:00 RI occurred near Iwo Jima, followed High OHC over the western Pacific and

by rapid intensification moderate wind shear

KALMAEGI 2025 WP Cat-4 41 kt/24h 11-05 00:00 → 11-06 00:00 Rainfall increased by ~3% (6 km), High OHC near the Philippines, influence of

wind speed increased by ~8.6% climate change

; severe damage in the Philippines

GAEMI 2024 WP Cat-4 40 kt/24h 07-23 06:00 → 07-24 06:00 Rapid RI after ERC completion and High SST and elevated OHC

pinhole eye formation

FUNG-WONG 2025 WP Cat-4 39 kt/24h 11-07 18:00 → 11-08 18:00 -- High OHC and weak wind shear near the Philippines

SHANSHAN 2024 WP Cat-4 35 kt/24h 08-26 00:00 → 08-27 00:00 RI near the Amami Islands, SST ~30°C, high OHC and low wind shear slow translation speed near the Philippines

AMPIL 2024 WP Cat-3 30 kt/24h 08-14 18:00 → 08-15 18:00 -- High OHC and low wind shear over the western Pacific

Table Structure

columns:

Column unit Description

typhoon - Name (year)

Peak intensity(IBTrACS) hpa/m/s Observed Pmin / Vmax

Translation speed m/s Mean translation speed

SST range °C Min-max SST along track (from ROMS)

Cold wake Δ T °C Max SST cooling within 2×RMW

CTRL Pmin error hPa Pmin RMSE (CTRL vs IBTrACS)

BAG Pmin error hPa Pmin RMSE (BAG vs IBTrACS)

Improvement (Pmin) % (RMSE_CTRL - RMSE_BAG) / RMSE_CTRL × 100

CTRL Vmax error m s⁻¹ Vmax RMSE

BAG Vmax error m s⁻¹ Vmax RMSE

Improvement (Vmax) % Same formula

Peak spray Msp kg m⁻² s⁻¹ Max azimuthal-mean spray mass flux

Peak spray enthalpy W m⁻² Max azimuthal-mean spray enthalpy flux

Rim fraction % Rim / total mass flux at peak

Table 1.a. Observational characteristics of ten selected rapid intensification (RI) cases (2024–2026) based on IBTrACS best-track data. Cat denotes the Saffir–Simpson category at peak intensity. RI rate is the maximum 24-h wind speed increase (kt 24h⁻¹) along the storm track. SST range indicates the minimum–maximum sea surface temperature along the storm track derived from ROMS simulations. ΔT_cw is the maximum SST cooling within 2×RMW after storm passage. V_tr is the mean translation speed averaged over the storm lifetime.

Typhoon Year Basin Cat Vmax(kt) Pmin(hPa) V_tr(m/s)

ERROL 2025 SI 5 138 919 3.3

HORACIO 2026 SI 5 138 920 4.8

MILTON 2024 AL 5 155 895 6.0

YAGI 2024 WP 5 145 907 5.1

ERIN 2025 AL 5 140 913 8.5

RAGASA 2025 WP 5 144 911 4.8

JOHN 2024 EP 3 105 956 2.2

KRISTY 2024 EP 4 140 926 6.5

MAN-YI 2024 WP 5 140 924 6.4

USAGI 2024 WP 4 130 934 6.4

BOLAVEN 2023 WP 5 165 897 7.5

KONG-REY 2024 WP 5 140 917 6.2

NEOGURI 2025 WP 4 124 936 5.4

KRATHON 2024 WP 4 135 922 2.5

HALONG 2025 WP 4 119 936 6.4

KALMAEGI 2025 WP 4 115 948 7.3

GAEMI 2024 WP 4 125 919 4.2

FUNG-WONG 2025 WP 4 115 943 6.4

SHANSHAN 2024 WP 4 115 935 3.7

AMPIL 2024 WP 3 110 939 5.7

SINLAKU 2026 WP 5 154 896 4.0

FYTIA 2026 SI 3 99 962 3.6

DUDZAI 2026 SI 4 124 940 4.0

NARELLE 2026 SI->Sp 4 124 933 6.5

GEZANI 2026 SI 3 109 956 5.2

GRANT 2026 SI 4 119 944 4.1

VAIANU 2026 SI 3 99 954 4.6

MAILA 2026 SP 4 124 930 1.8