Australian slang term for a hot and wet thunderstorm during the summer months. These thunderstorms hit almost exactly the same time (4pm) every day during the october/november period.

The storms and terminology have fallen out of use recently due to the evil boogeyman known as "global warming"
"Is that thunder?"
"Ya, it's 4 O'clock"
"4 O'clock special then?"
by count23 December 7, 2009
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