CHART: The incredible number of lightning strikes around Sydney during a thunderstorm this afternoon

Source: NSW Rural Fire Service

Lightning is a major cause of bushfires – something rural firefighters know all too well.

And as a storm swept through Sydney this afternoon, bringing hail and leading to a brief shutdown and delays at Sydney airport, the NSW rural fire service tweeted the map above showing just how tough conditions were as they battled a major grassfire near Canberra this afternoon, with appears to have destroyed at least 15 homes.

Each yellow dot is a potential disaster.

Rural firefighters across the state are currently dealing with 87 bush and grass fires, and at 6pm, 66 remain uncontained.

The ABC reports that one firefighter was injured fighting the Carwoola fire, near Queenbeyan, on the border with the ACT, and was taken to hospital with burns.

And you thought you had a tough day at the office.

Business Insider Emails & Alerts

Site highlights each day to your inbox.

Follow Business Insider Australia on Facebook, Twitter, LinkedIn, and Instagram.