One of Australia’s most major highways, the Hume Freeway linking Melbourne to Sydney, has seen some interesting traffic patterns as of late. It’s all thanks to the tar in the road literally melting under sustained 100-plus degree temperatures of a heat wave.
A good six-odd miles of the Hume outside of Melbourne in the southeast was melting a few days ago, as declared in this very matter-of-fact traffic advisory:
It’s not really that the whole road is melting, just the tar. (That’s the tar in tarmac.) Basically, the tar holds the solids of the road together, it gets hot and gooey, and the once-solid-looking road starts to melt.
Sustained temperatures cresting 100 and 110 degrees Fahrenheit are to blame, as NPR noted. It gave a further explanation of why the road itself would melt from an earlier report from the BBC when something similar happened in a 2013 heatwave in the United Kingdom:
“Asphalt is like chocolate — it melts and softens when it’s hot, and goes hard and brittle when it’s cold — it doesn’t maintain the same strength all year round,” an expert in road surface treatments told the British broadcaster.
The area has stayed sweltering hot over the weekend, as evidenced by this kangaroo taking a dip in someone’s backyard pool.