We are on the edge of the build up with showers and storms already in progress this week and that activity like to become more frequent in the next 2-3 weeks before daily rainfall returns from October.
Take a look at the national wrap to review the data sets underpinning the forecast here
Rainfall next 6 weeks
% chance of exceeding the median rainfall for the period September 10-October 24 2021
The forecast rainfall in the coming week over parts of the Top End is already above average in terms of frequency for this time of year. The rainfall intensity will likely increase rapidly once we lose the drier air behind cold fronts over southern Australia. That is the only mitigating factor to this heightened chance of above average rainfall for the northern parts. Moisture streaming out of the north, which we can see this week, is the likely cause of above average rainfall chances for much of the outback and remote areas, heading into the southeast. That said, you only need 1-5mm in some parts to be above average, given that a lot of this area is arid/desert climate.
Broader View of the north.
Temperatures next 6 weeks
% chance of exceeding the median temperatures for the period September 10-October 24 2021
No change since the last update, with above average temperatures expected for much of the state during this period. Heat levels set to become excessive over the north which is normal, given the build up, but these values could extend further south much earlier than normal. Overnight minima will also be well above average for this time of year helping to destablise the atmosphere to produce that above average rainfall chances.
Broader view showing the heat bias over the north.
I will have a state based short and medium term forecast later this afternoon looking at the forecast this week as we turn humid and stormy.