Freak storm dumps giant hail on Australia

New South Wales emergency services launched a "large-scale multi-agency response" after a supercell storm hit parts of the state’s North Coast on October 20.  They say they had more than 500 requests for help after the afternoon storm.

Some areas reported record-sized hailstones measuring 16 cm (6.3 inches) in diameter according to the Bureau of Meteorology.  The previous record for hail was 14 centimeters from a storm last October.

Footage from Coffs Harbour shows large hailstones raining down.

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9News described the storm as a "freak weather event," and reported that 400 people were evacuated when the roof of a shopping center in the Coffs Harbour suburb of Toormina collapsed under the weight of water.

7News reported that 50 mm of rain fell in the space of an hour in the Coffs Harbour area.

Footage posted on Instagram by Keiran James, shows hailstones covering the ground at a golf course in Sawtell.

The Bureau of Meteorology warned that giant hail and destructive winds were due to hit the Coffs Harbour area on Wednesday,, and told people to take safety precautions due to the extreme weather.

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Footage by Joshua Harrison shows large hail and damaging winds pelting a residential area. He said the video was filmed in Sawtell, a suburb of Coffs Harbour where fire crews were supporting emergency services with recovery efforts.

According to the Bureau of Meteorology, hail needs exactly the right conditions to form, and giant hail needs even more, varied factors to come together. This is why giant hail is quite rare.

Central Queensland had a combination of very cold, dry air in the upper levels and warm, moist unstable air at the surface. Once thunderstorms developed, the atmosphere was extremely unstable, which allowed hail to continue growing before it became too heavy and gravity finally took over, bringing the hail to the ground. 

People shared photos of the giant hail that shattered car windshields.