A dry airmass with a ridge in the region bringing settled skies to most of the state, is expected to continue for Wednesday. However a few areas of instability, about Cape York and over the Southeast inland may give rise to a few thundery showers, but nothing too significant and mostly isolated.
The weather turns more humid along the coast from later this week with morning and evening showers developing in onshore winds. The moisture over the coast will then travel inland, that will bring more widespread showers and thunderstorms by the weekend for southern districts as the trough in SA moves into QLD.
The showery weather may be heavy at times, however the bulk of the better falls may be south of the border into NSW.
Another low pressure system will be quick to approach from the west early next week and with a deep moisture profile, the rainfall could turn quite heavy in spots. That system will be easier to forecast once we get the first low off the board by the weekend.
Lets take a look
Rainfall Next 10 Days
Light falls under coastal shower activity and the odd moderate fall with isolated thunderstorm activity about the southeast and Cape York during Wednesday but otherwise the rainfall chances start to increase for the state from later this week. Scattered showers for coastal areas with a trough approaching from SA and the NT bringing showers and storms for southern areas of the state this weekend. Rainfall coverage will be determined by the placement of the trough this weekend and then the secondary trough and low passing through the eastern interior next week. The forecasts are relatively low confidence at this times, the weather is tending wetter as we go.
Thunderstorm Forecast Wednesday
Thunderstorms are expected to fire in isolated pockets through Cape York and down the Atherton Tablelands and over the southeast during Wednesday. Storms unlikely to be severe with moderate bursts of rainfall and gusty winds at best with the pulse storms.
DATA - More details can be found in the video at the top
00Z CMC - Surface Pressure Pattern and Rainfall Distribution - Next 10 Days
I am aligning more with the CMC and Euro on this sequence, the GFS is just not rendering the outlook as per the major data sets given that the GFS ensemble data is wetter than what is publicly available. At this stage we have 2 large scale rainfall events to watch through southern and eastern parts of the nation during this period. Also the tropics are expected to fire up in response to the record heat we have been observing during the past few days. The response to that is a sharp increase in convective activity. That has been my experience from living there for many years and this model sees that. The moisture deepens throughout the majority of the nation next week with the second system and the rainfall chance extend once again mainly over the eastern 2/3rds of the nation. WA may see more rainfall again with this first system during the coming 36hrs and once again with the developing 2nd system later in the weekend. Above average rainfall and generally below average temperatures (away from the tropics) is expected during this period.
00Z CMC - Precipitable Water Anomalies - Next 10 Days
Refer to the video above for more details.
00Z CMC - Precipitable Water Values - Next 16 Days
Refer to the video above for more details
00Z CMC - Rainfall Accumulation - Next 16 Days
Rainfall is expected to be heaviest in a band from southern WA through Agricultural SA into VIC and southern NSW and the ACT with the first feature. Storms for central and northern parts of NSW in the warmer sector of this system. The second system will provide more widespread rainfall and increase rainfall over the northern tropics and spread that throughout the eastern 2/3rds of the nation.
A closer look in. Your number will continue to evolve.
I will have the latest on all things rainfall and the modelling tonight - the divergence is still present across the board, but I will break down what is plausible and what is not in the update after 9pm