Australia's latest brush with extreme heat shows just how good weather forecasting really is
As a dome of heat developed over north and central Australia last weekend, parts of the country braced themselves for their first taste of summer temperatures well in excess of 40°C. Some areas expected their hottest temperatures ...
The southeast was on high alert, with searing heat and gusty winds expected, bringing the threat of extreme fire conditions through South Australia and Victoria on Monday and into New South Wales on Tuesday. The north and central parts of Australia were expected to swelter through the week.
But as the furnace drew closer, many people who kept a watchful eye on the forecast would have noticed something. In some parts of the country, the forecast bounced around in the lead up to the event.
For example, in the week leading up to the day of extreme heat on Monday, the forecast for Melbourne flip-flopped between approximately 35°C and 42°C, settling on 41°C for a couple of days before the event.
So what was it going to be? Just a very warm, but manageable day? Or the kind of highly unusual heat not experienced for several years?
Weather forecasting is a science, not an art
Predicting anything about the future, with accuracy, is hard.
Think about a forecast for your day tomorrow. You might predict that you will get up, eat breakfast, get the kids ready, go to work, finish a report, have a meeting, do some Christmas shopping, pick up the kids, and cook dinner.
But reality might differ from what you predicted. Your meeting might run late, causing you to skip the shopping, for example.
Temperature forecasts for Melbourne from the European Centre for Medium-Range Weather Forecasts changed over time. The blue line shows the forecast from a single high-resolution model, while the cyan bars show the spread of forecasts from an ensemble of lower-resolution models. Credit: ECMWF
Each image shows a forecast for Monday December 16 at 5pm AEDT (near the time of maximum temperatures in the southeast of Australia) from the same weather model with predictions made at different times, from 102 hours in advance (~4 days) to 18 hour in advance. The colours show the expected temperatures for the 5pm forecast. Credit: ECMWF