This weather phenomenon in Australia will haunt your nightmares

Arachnophobes look away now. In what must count as one of the most terrifying meteorological phenomenons, it's raining spiders in New South Wales.

In a process known as "ballooning" or "spider rain", millions of tiny spiders have descended on the town of Goulburn with cobwebs blanketing the surrounding fields.

"The whole place was covered in these little black spiderlings and when I looked up at the sun it was like this tunnel of webs going up for a couple of hundred metres into the sky," local resident Ian Watson told the Sydney Morning Herald.

"You couldn't go out without getting spider webs on you. And I've got a beard as well, so they kept getting in my beard," he added.

The process is thought to be a "dispersal techique" whereby spiders climb to the tops of vegetation and then use their silk to catch the breeze. It's thought they can travel for miles and miles this way.

As for why they've all descended upon one little town in Australia's Southern Tablelands, it could be to do with a localised flooding or heavy rain when lots of spiders are trying to escape all at the same time.

Fortunately for the residents of Goulburn, Martyn Robinson from the Australian Museum explained to the SMH that none of the spiders involved in this invasion are likely to be harmful. "There's nothing to worry about ... They'll all disperse once the weather conditions warm up," he explained.

You can find out more about the process of "spider rain" in the video below:

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