MODELS AND THE RAINFALL EVENT.

Lets have a look at where we stand across the data tonight.


GFS - LATEST UPDATE THIS EVENING

Has a solid band of rain passing through southeast Australia coming up from Friday into the weekend as the cold front and trough run into the moisture rushing in over QLD and NSW. The rainfall numbers have ticked up a little in the latest run for eastern SA. The latest model run DOES NOT have that large scale low pressure system in the upper levels as it did this afternoon (again this will come and go being a week out and model volatility). However with the SAM staying positive next week the rainfall bias should be over the eastern side of the nation and we are seeing that in the short term.

CMC

The rainfall again has remain unchanged in where it develops over the east, certainly some welcome rainfall for the southeast of SA and then the biggest rainfall looks to aim for VIC some parts of southern NSW. There is part of the boundary that gets trapped that lifts north into the Central parts of Australia this weekend before that erodes next week. Otherwise it is a dry picture next week, with modelling not keen on playing out the low pressure system that GFS had in the evening run. But also has less moisture than some other models too across the nation.

EURO

Euro has greater coverage of rainfall, but confines the heaviest rainfall into the southeast, over southern VIC and into northeast VIC and southeast NSW. Also some beneficial falls over parts of western NSW and that extends back into southwest QLD and southern and central NT. The weather following the front is also drier, with colder weather spreading over the southeast and eastern inland of the nation. The west looks dry under high pressure following the rainfall later this week.

KMA

The rainfall is again confined to the southeast with the heavier falls located over southern VIC as the front rolls through during Friday into Saturday. Has heavier rainfall up to 30-40mm through parts of NSW extending back to Central Australia before lighter falls is all that remains over the eastern inland. Light falls of SA. Light to moderate rainfall tomorrow over WA then dry for a week. Tropics see light to moderate showers as per the other models thanks to moisture moving through from east to west.

ACCESS G

Rainfall moves through SA with patchy rainfall during Friday but as the front moves into the moisture that races into the system from the east, widespread rainfall develops from that absorption and we will see rainfall increase dramatically over southern and eastern VIC and over NSW. Inland areas could get a good wet down with the trough lingering throughout the region into next week. No sign of that follow up system.

ICON

This model ignites the rain further east than the other models, pushing the front through quicker leading to rainfall that gets more widespread through NSW and central and eastern VIC. Barely a drop over SA and widespread showers over parts of the outback associated with a northward moving boundary.

UKMET

The rainfall ignites over VIC and western NSW on Friday as the front passes through the east where the deeper moisture is. The rain heavy over VIC with up to 1 months worth of rainfall attached to this front. Moderate rainfall through large pockets of NSW and outback areas of the NT into western QLD could prove productive for many that have gone without rainfall for a while. SA sees light rainfall and generally light falls for WA though falls could be moderate along the south coast. For the tropics more showers possible with an increase in moisture ahead of a dry surge later this weekend.

And finally I spoke about the IOD not looking too crash hot and hence why I am moving the rainfall chances of being above average further east and taking the chances down. This is normal and reflects the changes in models as weather is not static and it is foolish to have one forecast and stick by it out of pride. So you won't get that here.


The BoM updated the forecast model spread this afternoon for the IOD and as I alluded to in the Climate Update, the temperatures have now cooled down over the eastern IO with persistent easterly winds and drier air.

Old Forecast - Old Data

Current Forecast - Off New Data

The spring time twists and turns continue!!! More tomorrow.