On this day: Sydney’s biggest hailstorm
ON THE EVENING of Wednesday, 14 April 1999, the sky darkened ominously as a thick shelf cloud began to cast a shadow over Sydney. Residents report hearing the light patter of small hail pellets. But, at this early stage they scarcely suspected that these would turn into ice missiles hurled to the ground at speeds of 200km/h.
But, the hail did move in and calls soon flooded into the NSW Fire Brigade’s Sydney Communication Centre. At a call every 10 seconds, over the next five hours, more than 2000 requests for assistance flooded in meaning that the State Government was forced to declare a state of emergency.
Thousands of tonnes of hail fell on the city, with the largest hailstone measuring 9x8x8cm.
The most expensive storm in Australian history
April in Sydney is usually mild so the Bureau of Meteorology was caught off guard with no specialist staff on duty. The storm also defied predictions by moving over the city centre, rather than heading out to sea as expected.
Rather than hitting harmless stretches of water, the ice ripped through roofs, dented car bonnets and even damaged aircraft. In the end 20,000 buildings, 40,000 vehicles and 25 aircraft were affected.
The damage bill tallied up to $1.7 billion – more than the total cost of 1974’s Cyclone Tracy or 1983’s Ash Wednesday bushfires. It remains, in absolute dollar terms, the most expensive natural disaster in Australian history (although this is probably down to the cost of Sydney’s housing).
Hail storms underestimated
Today, hail remains an little-discussed problem for Sydneysiders. Professor Alan Jeary of the School of Engineering at University of Western Sydney says houses still aren’t built sturdily enough to withstand big hail events.
Sydneysiders remain complacent, he warns, especially if they have tile and slate roofs. It only takes stones 4cm in diameter, which fall once a year, to break new concrete. Stones 6cm in diameter fall once every two years and huge, cricket-ball-sized hailstones (8cm in diameter) rough Sydney up every 5-10 years.
Between 1968 and 2005 hail was responsible for over one-third of the country’s total natural hazard insurance claims and more than 75 per cent of these were in NSW.
READ MORE:
- The 10 most destructive tsunamis in history
- Top 10 worst floods in Australian history
- How to cyclone-proof your house
