Flowers appeared early in the ACT in an unusually warm August. Photo: Michelle Kroll.

The Australian Capital Territory is expecting a warmer and wetter than usual spring, with the Bureau of Meteorology (BOM) declaring a La Nina observation after a winter characterised by a split personality.

The second warmest August on record, with an average temperature of 16.7 degrees, caused by westerly winds and high pressure, resulted in average minimum and maximum values ​​that were above average.

To find out the warmest August in Canberra, you have to go back 42 years to 1982.

BOM climatologist Hugh McDowell said that while the first two months of winter were the coldest in about a decade, the warming trend continued.

“So while it is significantly colder than ever before, compared to historical data, even these first few months have been average or above average,” he said.

The average daily maximum temperature at Canberra Airport was 14.0 degrees Celsius, 0.6°C above the long-term average of 13.4°C. The average daily minimum temperature was 1.0°C, 0.2°C above the long-term average of 0.8°C.

It was a relatively dry winter, with rainfall from June to August being below average across the territory.

While some fear an early spring could herald a long, hot summer, Mr. McDowell said that’s not necessarily the case.

Currently, climate factors are neutral, but temperatures in the Tasman Sea are above average, which should provide a bit more moisture and warmth in the atmosphere this spring.

“The weather forecast for Canberra and the Australian Capital Territory region indicates there is a greater chance of warmer than average conditions,” Mr McDowell said.

“It’s not an exceptionally strong signal, 60 to 70 percent higher than the average maximum and minimum temperatures.”

There was also a greater likelihood of above-average precipitation than in dry conditions.

“There will be some dry periods, but the weather will probably even out and be a little wetter,” he said.

There was twice the chance of a La Nina phenomenon, which is typically associated with wet conditions, bringing rain from the east.

“But that’s still only a 50 percent chance, so there’s still a 50 percent chance we see neutral conditions,” McDowell said.

“So I would say the forecast includes the likelihood of a La Nina event and a rise in temperatures across the Tasman Ranges.”

However, the forecast of rising temperatures was “probably a signal of climate change in some way” because the phenomenon repeated itself every year.

Even if the Australian Capital Territory had neutral weather conditions, this would not mean that spring and summer would be less dangerous, as the risk of severe thunderstorms could increase.

“So you might lose the widespread increased risk of widespread rainfall, widespread flooding. But you might actually see an increased risk of isolated thunderstorms and damaging wind events with small thunderstorms, hail and flash flooding,” Mr McDowell said.

“So whatever route you take with these drivers, it may result in a different risk profile, but not necessarily a lower risk.”

Mr McDowell said the winter had brought patterns the bureau had not seen before and forecasting was becoming increasingly difficult.