A deep trough could actually deliver some of the wettest weather to the nation, right in the heart of the nation this weekend. It is not very often you say that in this country. Inland moisture is building up dramatically in line with the seasonal shift up north but also thanks to the Indian Ocean Dipole and the elevated SSTs in the Coral Sea as well. The moisture is placing the interior of the NT as the meeting place for all that moisture.
A trough is likely to lift this into showers and thunderstorms from Saturday with widespread rainfall possibly continuing into Sunday and Monday before contracting east.
For the north, scattered showers and afternoon storms becoming more numerous later this week and next week.
Lets take a look
Rainfall for the coming 10 days
Could see some decent falls for the first time since last wet season for southern areas of the NT, bordering the APY Lands and points towards the east. Some of the falls could exceed the seasonal rainfall values for Spring. In the north the falls are more scattered but could be heavy at times over the Darwin Daly and the Arnhem Districts where some locations could see 50mm. Otherwise the central parts will see very isolated falls through the Barkly.
The south looks wet.
Once again, the moderate chance of thunderstorm activity on the southward moving seabreeze front over northern areas of the Top End and also along the Tiwi Islands during the afternoon and evening, Hector the convector in full swing! Not a big boy but he is getting larger each week.
Euro 00z - Surface Pressure Pattern and Rainfall Distribution - Next 10 days
The models are well place on the short term forecast package with a front passing through the southeast of the nation Wednesday and Thursday bringing a burst of showers. Maybe some thundery showers and gusty winds over the outback of SA, western NSW and southern NT into QLD with this feature later tomorrow. Now the nation remains quiet until the weekend when we have the deepening low pressure trough over Central Australia combining with deep moisture throughout the interior, this allowing a large scale shower and thunderstorm event develop. The areas of greatest impact likely to be southern NT, northern SA and western NSW and QLD at this stage. This area of low pressure likely to slowly creep through to the east. The placement of this event is what the models are struggling with and I will have further to say after 9pm, but at this time the rainfall looks heaviest through southern QLD, NSW and northern VIC. Out west another strong cold front is expected to bring a further burst of colder than normal weather with showery periods early next week. IF this front comes in from the west earlier than GFS, than we will see a clearance of that system over the east quicker, but there is not great guidance upon that idea. Therefore the trough over the east may take the best part of next week to lift off the east coast but the moist unstable airmass may continue if the front does not arrive. Up north, baking weather with showers and thunderstorms in the afternoon and evening, in random scattered locations.
Euro 00z - Precipitable Water Anomalies - Next 10 days
This again paints the picture such as the GFS with the movement of moisture through the nation being repeated multiple times during the coming 7-10 days but if you watched the video, you see this trend continue. That supports the forecast bias of rainfall in the short and medium term with higher chances of above average rainfall through northern and eastern Australia. For the west, dry air behind cold fronts, will suppress rainfall for inland areas of the state and while keep temperatures colder than normal in the southwest inland, it will also stop rainfall developing for the medium term in that northwest corridor.
Euro 00z - Rainfall Accumulation - Next 10 days
Rainfall accumulation across the nation carries a low confidence from the weekend and as outlined in the video surrounding the GFS, it comes down to placement, scale, intensity and speed of the systems progress through the nation. The higher chance of rainfall can be found in the shorter term with this weakening cold front.
A closer look in
GFS 00z - Rainfall Accumulation - Next 10 days
Refer to the video surrounding the crazy outputs from the GFS over the past 24 hours and where do we go from here and can we take it seriously?
I will have the full model wrap on all things rainfall and severe weather potential coming after 9pm. As you can see the confidence is not especially high in this outlook which is normal for spring.