Around 500 schools will be closed across NSW as 'catastrophic' fire conditions threaten highly-populated areas around Sydney, Wollongong and Newcastle. Residents in the affected area are being warned to avoid unnecessary travel, and to leave their homes if they were even a little bit unprepared. Read more here: https://ab.co/2NA7RnQ For more from ABC News, click here: https://ab.co/2kxYCZY If you're in Australia, you can watch more ABC News content on iview: https://ab.co/2mge4KH Subscribe to us on YouTube: http://ab.co/1svxLVE Go deeper on our ABC News In-depth channel: https://ab.co/2lNeBn2 You can also like us on Facebook: / abcnews.au Or follow us on Instagram: / abcnews_au Or even on Twitter: / abcnews