With a national rainfall average of just 4.83 millimeters, Australia has achieved the driest September since records began being kept in the year 1900.
The data was released by the Bureau of Meteorology on Monday, at a time when fires were raging out of control in both Victoria and New South Wales, despite the fact that there were warnings about the possibility of flash flooding later in the week.
A positive Indian Ocean dipole, the freshly declared El Nio, and the long-term repercussions of the climate crisis contributed to total rainfall that was 70.8% below the 1961-1990 average for the month of September.
According to the BoM, high-pressure systems predominated in September, making it one of the driest months overall since records began being kept. These systems were responsible for bringing steady weather conditions and cloudless skies to the majority of the country.
With a national mean temperature that was 2.43 degrees Celsius higher than average, September 2018 was also the third warmest September on record in Australia.
In several states, the temperature continued to climb much higher. The state of Western Australia experienced its warmest September on record, while the states of New South Wales and Victoria experienced their second warmest Septembers. These three states also had their warmest September days on record for the month of September.
“The high-pressure systems were the main influence for our warm and dry weather across Australia throughout September,” said Nadine D’Argent, a climatology specialist with the Bureau of Meteorology (BoM).
The national mean maximum temperature was 3.38 degrees Celsius higher than average for September, making it the second-highest on record for the month.
On Monday afternoon, there were three fires that could not be contained in Victoria, and areas of the state were issued a warning about the possibility of flooding and damaging winds in the coming days.
As of Monday afternoon, there were 70 fires still burning in New South Wales, 13 of which had not been brought under control.
Mount Tanner and Leeka in Tasmania are under a bushfire emergency alert, which has been issued for certain locations.
On Monday, a total fire ban went into effect in the Mallee region of Victoria because temperatures that were above 30 degrees Celsius and winds brought on by an incoming cold front.
The Bureau of Meteorology predicted that the front would move through the state on Tuesday, bringing with it rain and severe wind gusts of 90 to 100 kilometers per hour through the central and eastern ranges.
Jason Heffernan, chief fire officer for the Country Fire Authority, stated that the authorities were anticipating that the front would have an effect on fire grounds and encouraged communities to get ready.
He told her that “that could mean you need to take action in the very early hours of the morning.” This frontal system will begin to exert its influence starting late tonight and continuing into the early hours of tomorrow morning.
The Bureau of Meteorology said that Tuesday might see severe rains, which could result in flash floods, particularly along the eastern ranges.
Then, on Wednesday morning, it was anticipated that a low-pressure system would form in the north-eastern region of Victoria and move towards eastern Victoria during the course of the day. This system was anticipated to bring additional precipitation, cooler temperatures, destructive wind gusts, and the possibility of flash flooding, particularly near the ranges.
According to senior meteorologist Angus Hines, the amount of rainfall that is likely to fall over the next few days might approach 100 to 150 millimeters in some regions, with the highest totals anticipated in the Gippsland region.
He predicted that the slightly cooler conditions that were expected to prevail in NSW on Monday would only last for a short period of time, with temperatures being forecasted to soar back up into the mid-30s on Tuesday. The highest temperature expected in Sydney for the month of October was 33 degrees, which is around 11 degrees higher than the average.
He predicted that there will be a significant amount of wind. That results in an increased risk of wildfire in a number of locations in New South Wales.
According to Hines, the “striking shift” in weather that is currently moving across Victoria will reach southern sections of New South Wales on Wednesday, bringing significant rains to some of those regions.
He stated that it was anticipated that the low-pressure system will move away on Friday, taking the wind and rain with it, but that the temperatures would remain lower into the weekend.