The 1999 Sydney hailstorm was the costliest natural disaster in Australian history, causing extensive damage along the east coast of New South Wales. The storm developed south of Sydney on the afternoon of April 14, 1999 and struck the city’s eastern suburbs, including the central business district, later that evening.
The storm dropped an estimated 500,000 tonnes of hailstones in its path. Insured damages caused by the storm were over A$1.7 billion, with the total damage bill (including uninsured damages) estimated to be around A$2.3 billion, equivalent to US$1.5 billion. It was the costliest in Australian history in terms of insured damages, overtaking the 1989 Newcastle earthquake that had resulted in A$1.1 billion in insured damages. Lightning also claimed one life during the storm, and the event caused approximately 50 injuries.
The storm was classified as a supercell following further analysis of its erratic nature and extreme attributes. During the event, the Bureau of Meteorology was consistently surprised at the frequent changes in direction, as well as the severity of the hail and the duration of the storm. The event was very unusual, as the time of year and weather conditions in the region were not conducive for a severe thunderstorm to form.
The downpour of an estimated 500,000 tonnes of hail across Sydney suburbia resulted in widespread damage on the coastal suburbs in its path. Insured losses due to the disaster reached roughly A$1.7 billion, with total costs estimated to be around A$2.3 billion. The storm was the costliest natural disaster ever to hit Australia in terms of insured losses, surpassing the 1989 Newcastle earthquake by around A$600 million.The areas that incurred the most damage were between Lilli Pilli and Darling Point, located 25 km (16 mi) apart on the coastline of Sydney.
The vast majority of damage was done by hail and rain. Approximately 24,000 houses were significantly damaged, with many suffering water damage through the holes in roofs that the large hailstones created. The stones were estimated as travelling at up to 200 km/h (120 mph) in some periods of the storm, causing indentation damage to around 70,000 vehicles. Twenty-three aeroplanes and helicopters at Sydney Airport were reported as having incurred notable damage from the hail, caused by the inability to place them under hangars in time to avoid the storm. This has been significantly attributed to a lack of warnings from the Bureau of Meteorology, who had expected the storm to continue moving further out into the Tasman Sea in the north-northeasterly direction in which it had previously been travelling.
The most significant insurance costs were in the areas of residential property damage with 31.8% of total payments, motor vehicle damage with 28.6% and for properties which service the commercial and industrial sectors at 27.5%. Damage to aviation property, mainly planes at the vulnerable Sydney Airport, amounted to 5.9% of the claims, while 5.8% of all insurance payments were made for ‘business interruption’ and 0.4% for damage to boats as well as other miscellaneous claims.
The storm caused one fatality; a 45-year-old man, who was fishing about 100 metres (300 ft) from the north shore of Dolans Bay in the Port Hacking estuary, was killed when his boat was struck by lightning.Fifty injuries were recorded, caused by flying objects, road accidents due to poor visibility and smashed windscreens and other factors.
