Sydney residents captured huge shelf clouds rolling into the Australian city. (Jenny Starrs/The Washington Post)

An enormous shelf cloud shocked onlookers as it rolled off the Pacific ocean toward Sydney’s Bondi Beach Friday afternoon.

“People were running from the streets to capture the unbelievable cloud formation,” eyewitness Hannah Murphy told CNN.

Photographs and videos show a tall and menacing cloud wall that steadily encroached on the coastline.

“This is a pretty significant one, plus it’s been a warm day, a lot of people are out – particularly at Bondi – and this huge mammoth storm just started rolling up the coast and of course social media went atomic,” photographer Nick Moir, of the Sydney Morning Herald, told Sky News.

On Twitter and Instagram, the feature quickly earned the moniker “cloud tsunami.”

The Australian Bureau of Meteorology issued a severe thunderstorm warning as it blew ashore mid-afternoon, cautioning large hail, heavy rain, and damaging winds were possible.

“All the dynamics of the atmosphere came together for a short time,” Mohammed Nabi, a Bureau of Meteorology forecaster, told the Sydney Morning Herald. “It was a short, sharp event.”

As the storm passed, Sydney’s temperature dropped from 83 (28.3 Celsius) to 69 degrees (20.6 Celsius).

“[The shelf cloud] is created by a cold outflow from a thunderstorm lifting the moist air very abruptly, it is an outflow feature from a thunderstorm,” forecaster Christopher Webb told The Daily Telegraph.

“When the rain from the thunderstorm comes vertically down it drags the air with it, it spreads horizontally and forms a gust front, you get the humid air being lifted abruptly from the outflow of the thunderstorm.”

Severe weather has hammered parts of Australia throughout the week. On Tuesday and Wednesday, heavy thunderstorms slammed the southern part of the county.

[Close-call lightning strike unexpectedly caught on video in South Australia]


Just caught this storm coming in from the south. Look out Bondi! @canonaustralia #sydneystorm #canon5Ds #24-105mm

A photo posted by guysebastian (@guysebastian) on

#cloudtsunami #bondi #bondibeach #sydney #australia #nofilter

A photo posted by Margarida C. (@margarida_cc) on

A Chinese tourist watches storm clouds moving along the coast towards the city of Sydney, Australia, November 6, 2015.(REUTERS/David Gray)



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