A powerful cold front moves across southern Australia with damaging
to possibly destructive winds and low level snow.
Satellite shows that swirl of cloud into a deep
low pressure system which tracked over Adelaide overnight.
Now this system is moving towards the east with a large pick
up in weather expected across southern Queensland,
New South Wales, ACT and Melbourne.
We have a look at the rainfall observations.
As that low tracked over Adelaide,
we saw three stations break their daily May records.
Now that was at Mount Lofty, Parafield and Edinburgh Air Force
Base. In the hours since midnight this morning,
there's been some stations in South Australia which have recorded
damaging wind gusts in excess of 90 kilometres an hour.
Now having a look at the Severe Weather Warnings,
they stretch from the Nullarbor in South Australia eastwards
into much of New South Wales, the northern fringe of Victoria,
however, that's expected to sink southwards tomorrow
and parts of the south-east, including Toowoomba,
the southern reaches of the Sunshine Coast and the Gold Coast.
Now this carries with the
risk of damaging wind gusts in excess of 90 kilometres an hour
however, there may be much smaller elements in there with showers and storms
which may bring down some of the brisk winds to the surface,
which will put us into that next category of destructive wind gusts in
excess of 125 kilometres an hour.
Now if we look at the forecast wind and rain, we can see the current situation
with that cold front making its way across New South Wales and that low
pressure system sitting up in the Mallee and Wimmera of Victoria
with a settling down of the wind conditions over South Australia.
And then as we move forward, we can see Canberra being affected later tonight,
Sydney and then also up extending up rather
into the New South Wales coast.
Now overnight into Tuesday we will start to see
what was previously in a weak wind pattern.
Melbourne will start to see some of those south westerly winds come through
and which is going to warrant that
Severe Weather Warning for damaging winds.
And as we move through into Wednesday, we can see
lots and lots of westerly wind or Tuesday into Wednesday
we can see lots of westerly winds still coming across the Great Divide
there and that will provide yet another night of some pretty damaging
winds, at least around the southern parts of the New South Wales Great Divide.
Now if we have a look at the winds that are sitting
one and a half kilometres above the surface,
these are very useful for forecasters because the winds are above the surface
and don't really interact with topography and hence friction
and give us a really good idea as to where the damaging winds will be.
And so it's no surprise all of these darker
colours are lining up with the current Severe Weather Warning largely.
And then as we move into tonight, we can see some very strong winds
starting to pick up around the Great Divide.
Now, this is going to be of particular concern,
especially given the past three months have been really sodden
with lots of rainfall
so a lot of the trees, a lot of the power poles
are going to really struggle to stay upright in this brisk wind.
And not only that, we've do have lots of people who are flood affected
and displaced and may be in temporary or structured, temporary accommodation
or structures that aren't engineered to stand some of these wind stresses
so it's important to be very conscious of this, especially
in the northern part of New South Wales as we move into tonight.
And we can see some very, very dark colours there.
There was a hint of black just before I paused it,
that's hinting at winds of 135 kilometres an hour.
So that's extraordinarily strong winds and the downslope winds
will affect areas along that Great Divide and coastward.
But as we move into Tuesday, there is
a patch of winds through Victoria and then Tuesday night
we will see some of the damaging winds persist,
including Sydney and then southwards towards Mallacoota.
Now if you have a look at the
forecast winds here, so I'll just bump it
along to
the snow.
So our apologies for that.
We do have the snow levels here.
That wind that's coming up from the south-west
introduces pretty cold air to the area.
So Tasmania, Victoria, south-eastern
New South Wales and even up to the
Central Tablelands of New South Wales,
by Wednesday morning, we'll see the snow levels fall to 600 metres.
So on the Alpine Resorts, looking at 20 to 50
centimetres of snow accumulation, and then areas such as Mount Macedon,
the Dandenongs, Canberra, Brindabellas,
Oberon, Orange and Bathurst, Katoomba
could also see some snow flurries as this system makes its way through.
If we have a look at the minimum temperatures, they're not going to change
too drastically, even though we've got cold air over the region
because that wind keeps mixing and thermalising the low level air,
we won't really see that until Thursday when the
very strong
winds move off into the Tasman and we're starting to see broad
areas of single digits or low single digit temperatures.
We have a look now at the forecast wave heights.
We've got waves around eight metres, very long period
waves too affecting the exposed coast of South Australia
and a lot of that water is piling up along the coast.
And with that piling up, it's going to move an anomalous mass of water
along the coast and we'll see some of the tides
exceed the Highest Astronomical Tide for the year.
So it will affect
the South Australian area very strongly on Monday and Tuesday
and then it will start to move around into western Victoria
and on Wednesday we could see some nuisance
flooding around the eastern reaches of Port Phillip Bay.
And that's it from the Bureau.
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And please follow the advice of emergency services.