Some parts of northern Victoria received have received more than four times their average December rainfall, after a low pressure system combined to deluge much of the state.
The Bureau of Meteorology said the system, in northern Victoria and Tropical Cyclone Owen, in Queensland’s far north, were linked by an upper-level trough.
Here's the month to date rainfall for #Victoria for December. This shows that regions shaded green, blue and purple have already received more than their typical December rainfall with some areas clocking more than 4 times their average. https://t.co/SSRyYFQKrtpic.twitter.com/yX5p6w44Iw— Bureau of Meteorology, Victoria (@BOM_Vic) December 16, 2018
The trough developed the low-pressure system, over south-eastern Victoria and dragged Owen towards the Queensland coast.
The BoM’s senior meteorologist Dean Stewart said since last Thursday, areas of the Mallee and Wimmera, and north-east, received most of the rain.
Eldorado received 201mm of rain and Everton 198mm, while in the west Birchip suffered flooding from a 195mm soaking, while Woomelang copped 173mm.
Many centres received more than one hundred millimetres, over the four days from Thursday, last week.
Here's the 2-day rainfall for last weekend across #Victoria. Some notable 48 hour rainfall totals (to 9am this morning) include: 91.4mm at Mallacoota,, 42mm at Puckapunyal, 25.6mm at Pakenham Upper, and Birchip recorded a further 25.2mm. Find yours here: https://t.co/B2xuQa1e1Jpic.twitter.com/7GvTRELWxh— Bureau of Meteorology, Victoria (@BOM_Vic) December 17, 2018
“We had a low-pressure trough approach from the west, and as it moved into the state, it developed into a low-pressure system, that triggered some initial heavy rain on Thursday,” Mr Stewart said.
“The surface low tracked up into NSW and over Victoria, and we were left with this very humid and unstable air over us on Friday, that lingered until the weekend.
“The atmosphere was so moist and unstable, it was like a tropical airmass over us.”
The low developed over the north-east, and the ranges intensified the rain.
“We do get some humid spells in our summer months, but it’s not often we have high instability, leading to such widespread thunderstorm activity,” he said.
“That humidity was lingering across the state, with the low that caused it.
“It was hanging around right through the weekend, which maintained unstable conditions that led to the heavy downpours, over the weekend.”
Mr Stewart said the first half of the week was likely to experience dry conditions, although another low-pressure system was moving across far northern Victoria and southern NSW.
He said it was expected to bring showers, “not the extreme rainfall we saw.”
Jim Renkin, Lima South, said the 55mm he received was “very welcome.
“It was looking like a very ordinary spring, and it’s finished it off very well,” Mr Renkin, who runs 3500 sheep and 350 cattle, said.
‘It certainly kicked away all the perennials; there is quite a bit of green shoot around.
“The phalaris, coxfoot and ryegrass kicked along, especially where the country has been cut to make silage – it’s really good.”
Chris Rickard, who farms near Birchip, said his property received more than 200mm, from Thursday, until the weekend.
“For a cropping program it’s very beneficial, it’ll be hanging around and soaking in,” he said.
“I’ve still a bit of the harvest to do, then, as soon as it dries out and the weeds come up, I’ll be on the boomspray.
“I’ll be busy saving moisture in the soil.”
“I’ve got a full profile of moisture now, and I don’t want to lose it.
“That was our biggest problem this year; we couldn’t get any more than 10mm of rain in one run.”
Leah Toose, Lake Marmal, said the property received about 125mm of rain, since last Thursday.
The Toose family has a 2000 hectare cropping property, growing cereals and vetch.
She said the rain was welcome, as the harvest had been completed and hay stored.
“It will soak in fairly quickly, the ground was dry, and we haven’t had any decent rain all year, it’s not been a good year, at all, really,” Ms Toose said.
“We had some heavy rain around January, on another block, and it produced some really good crops,” she said.
“It’ll last a while, as it’ll get the crops off to a good start.”
Chris Kelly, Woomelang, said he received 190mm and had ordered canola seed, due to the good moisture profile.
“The crop residue has helped the moisture remain in the soil, pretty much where it’s fallen,” Mr Kelly said.
“The ground has been incredibly thirsty, and I think the soil moisture will be very good when we do tests in February or March.”
He said he was hopeful there would be follow up rain, in March, and it was a good sign to see the rain coming from the east coast.
Farmers were likely to have a full cereal and pulse planting program, following the rain.
“I don’t think a lot of people will fallow, with that sort of moisture bucket,” he said.
In November 2010, he said the area received similar falls, and only needed top-up rain to finish off the crop.
“If you have got the bucket full, you don’t need a lot more to come, for a good crop.”