Sydney people are known for being weather whingers. They're not quite in Darwin's league for freaking out about cold which isn't actually that cold, but they're not far off.
But on Friday night, Sydneysiders might actually have cause for genuine complaint when the temperature in parts of the city drops as low as minus 4. Yes, four degrees below zero.
Official Sydney temperatures are recorded at Observatory Hill, a small hump of land near the southern end of the Harbour Bridge. The coldest it ever got there was 2.1 degrees and Friday night is tipped to be just four.
But it's always colder further from the coast, and large parts of Sydney will go a lot lower than that. Penrith in Sydney's west is tipped to dip to minus two in the early hours of Saturday morning.
We wrote about Penrith over summer, outing it as Australia's hottest suburb. Just as heat gets trapped on Sydney's western plains in summer, cold air sinks there at night in winter. That's why Richmond in Sydney's north-west will reach minus four, or so the Bureau predicts.
DID YOU KNOW?
The coldest temperature ever recorded in Australia (we're talking mainland and/or Tassie -- not including Antarctic territories) was at the tiny NSW ski resort of Charlotte Pass.
That was a night of minus 23 back in the 1990s. The weather station there has since been decommissioned but the ski resort still records unofficial weather data.
According to the Bureau of Meteorology the coldest ever temperature in the Sydney basin was recorded on one frigid night in July 1970, when Richmond reached minus 8.3. Brrrr.
Camden in Sydney's south-west also gets cold, and has dipped as low as minus 6 in the past. Friday night is expected to bottom out around minus 2.
The good news is that days are expected to be sunny in Sydney over the weekend, with highs of 22 by Sunday. Melbourne, Perth, Hobart and Adelaide will all be showery with top temps in the mid teens, but elsewhere it should be mostly fine.
Meanwhile, if Sydney folk think Friday night is going to be cold, spare a thought for Canberrans, who will endure minus 7. The nation's capital has dipped below zero on 18 of the 21 July nights to date, primarily because it's been so dry.
And Darwin? They're heading for a minimum below the magic 20 mark at a positively Antarctic 19 degrees. We're not sure how they'll cope.
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