Home / Local / 65% chance of more cyclones than usual: BOM
11 October 2021
The Bureau of Meteorology (BOM) says there is a 65% chance of more tropical cyclones than average this coming storm season, which starts next month and runs until April.
In its outlook released today, BOM says the increased likelihood of La Nina development in the tropical Pacific Ocean and average to warmer-than-average sea surface temperatures to the north of Australia have influenced this year’s tropical cyclone forecast.
“The number of tropical cyclones in the Australian region is generally higher with La Nina,” BOM said. “Outlook accuracy for the Australian region is high.
“The outlook indicates that an average to slightly-above-average number of tropical cyclones is most likely in the Australian region and all sub-regions for 2020–21.”
BOM says even if La Nina doesn’t develop, some effects often associated with the flood-inducing weather system can still occur as tropical Pacific climate indicators approach La Nina thresholds.
In La Nina years, the first cyclone to make landfall on the Australian coast typically occurs earlier than normal, around the middle of December. During average years, the date of the first tropical cyclone to make landfall is usually in early January.
The Australian cyclone season sees an average 9-11 storms, four of which typically cross the coast.
BOM says WA has a 61% chance of more cyclones this season although it did say the outlook accuracy is low.
For the east, which includes huge parts of north Queensland, there is a 66% likelihood of more cyclones than average. Again the outlook accuracy is low, BOM said.