Severe Tropical Cyclone Harold

1 – 10 April 2020

Preliminary Summary

Track of Severe Tropical Cyclone Harold
All times shows are in Australian Eastern Standard Time (AEST), that is UTC + 10 hours.

Severe tropical cyclone Harold was a strong, long-track cyclone, notable for affecting three different South Pacific island nations (Vanuatu, Fiji, and Tonga) while at category 4 strength or higher. It caused devastation in Vanuatu where it struck at category 5 strength. With estimated peak mean winds of 230 km/h and gusts to 325 km/h (Dvorak T number 7.5), it was the strongest tropical cyclone to affect the Southwest Pacific basin since Severe Tropical Cyclone Pam in 2015.

Severe tropical cyclone Harold developed from a tropical low initially detected to the west of the Solomon Islands. The system tracked east-southeast while developing and was named on the afternoon of 2 April. Conditions were very favourable for further development, and on 3 April the system rapidly intensified from category 1 to category 4 in 24 hours while heading southeast towards Vanuatu. It moved across Vanuatu at category 5 strength, maintaining this intensity for approximately 24 hours. Thereafter it maintained an east-southeast track and weakened slightly to category 4 intensity, which it held for another two days while passing close to the southern most islands of Fiji and Tonga. On 9 April, Harold passed south of 25 degrees south and began to weaken, before undergoing extratropical transition south of 30 degrees south on 10 April.

Even as a tropical low and category 1 system, Harold caused considerable impact in the Solomon Islands. It destroyed 57 houses, washed ashore 3 ferries (due to waves and storm tide), and caused widespread power outages and flooding in Honiara. Tragically, the largest loss of life caused by Harold occurred during this category 1 phase, when 27 people were washed overboard by large waves and presumed drowned from the ferry MV Taimareho in Ironbottom Sound in Malaita Province.

Severe Tropical Cyclone Harold made landfall on Espiritu Santo Island in Vanuatu at 18Z on the 5 April as a category 5 system, the first such impact on Vanuatu since Pam in 2015. Winds unroofed homes and downed trees in the main city of Luganville, with 50 to 70% of buildings in the city damaged. More broadly, approximately one third of Vanuatu's population were affected across seven islands, with communications lost in most affected areas. Rainfall up to 450mm caused widespread flooding. The most extreme damage occurred in Pentecost, where Harold made its second landfall near peak intensity and damaged 68% of all structures. Two deaths were reported from Malo Island. It was estimated that Harold left 160,000 people homeless (a little less than half the population of Vanuatu). International aid for the recovery effort was slowed due to extra quarantine restrictions for the concurrently occurring COVID-19 pandemic.

Severe Tropical Cyclone Harold made landfall on the southern Fijian island of Kadavu at around 00Z on 8 April as a category 4 system. Wind gusts of 139 km/h were recorded at both Momi (southwest of Nadi) and later at Matuku Island before the weather station there was destroyed by the cyclone. Heavy rainfall and flooding affected several communities across Fiji. Power outages affected much of Fiji's central and western divisions, including Nadi where wind gusts reached 95 km/h. A tornado occurred over Nausori which destroyed houses and one school, another occurred in Nakasi, and a third occurred in Nasinu. One death and 26 injuries were recorded across Fiji, with 1919 buildings damaged.

The centre of Harold passed to the south of Tongatapu in Tonga early on 9 April, still at category 4 strength. Peripheral winds caused power outages across the islands, and some buildings were unroofed. Wind gusts at Fu'amotu station on Tongatapu reached 139 km/h. The southern parts of Tonga experienced a storm tide reaching approximately 0.9m above highest astronomical tide, which destroyed three tourist resorts west of Nuku'alofa.

Extreme values during cyclone event (estimated)

Note that these values may be changed on the receipt of later information

Maximum Category: 5
Maximum sustained wind speed: 230 km/h
Maximum wind gust: 325 km/h
Lowest central pressure: 920 hPa