Delay in start to wet season
THE wet season for North Queensland is forecast to start later this year than normal.
Bureau of Meteorology tropical climatologist Greg Browning said that usually the first 50mm of rain would arrive in the first half of November.
“But the current forecast is suggesting the odds are tipped towards it being a bit later than usual,” he said.
“Unfortunately it’s really just the coast of Queensland at this stage that’s seeing those reduced odds, most other places are about average.”
The information was released through BoM’s first Northern Rainfall Onset Outlook.
Two more will be released at the end of July and August.
Depending on how smoothly the crushing season goes, the forecast of later showers is welcome news for Burdekin’s sugarcane growers.
Canegrowers Burdekin general manager Wayne Smith said growers liked to finish their harvest by mid- November, so the timing could potentially be perfect.
“If the rain comes in late November and we’re finished, it certainly would be handy,” he said.
“But it’s one of those things we can’t control.
“Even though the bureau is getting very good at forecasting, they can’t be exact so timing is everything for us.”
The northern rainfall onset occurs when enough rain has fallen to stimulate plant growth after the dry season, the BoM says.
This is defined as the date when at least 50mm has accumulated after September 1.
“Statistics show in general parts of coastal Queensland and the western Top End receive the first useful rainfall by late October or early November, and this spreads further south and inland over ensuing weeks,” the BoM outlook reads.
“The southern inland regions of the Northern Terri- tory and western parts of Western Australia usually have the latest northern rainfall onset, about mid- January.”
Mr Browning said the outlook was another way at looking at the transition between the dry and wet seasons.
“This ( outlook) was designed after consultation with the agriculture industry ... and they’ve said that first 50mm after the dry season is enough to trigger pasture regrowth,” he said.
Mr Browning said the outlook was not completely based on historic results.
“It’s pretty much pulling all the information we can currently get, from satellite information, rainfall stations and temperatures right across the globe,” he said.
Although Ross River Dam is sitting at a healthy 83 per cent capacity after heavy downpours at the start of the year, a late wet season start could be an issue. A possible El Nino weather pattern could also affect rainfall.
At the moment, climate influences were neutral, Mr Browning said.
“Although there is an expectation El Nino may develop later in the year, it’s certainly not a done deal though. Recently we’ve upped the likelihood of El Nino developing to 50 per cent, which is twice the normal rate,” he said.