The upper low is working its way into the eastern inland today and areas of middle level cloud are already in place over the region in advance of the upper low moving in from the west today.
Scattered showers are forecast to develop along the eastern periphery of the feature today before that sweeps further northeast and east during the coming 2 days before a surface develops offshore the east coast of QLD on the weekend before conditions improve as high pressure knocks the system out further into the Coral and Tasman Sea.
Mechanics and timing for the event
Severe Weather Watch - Mid Week - Heavy Rainfall
The thunderstorms over the inland will likely lead to some isolated pockets of severe weather risks. Along the coast, strong winds and heavy showers with a low running parallel to the coast before clearing by Saturday.
Thunderstorm Forecast Wednesday
Thunderstorms are possible during early afternoon over the southwest inland and will also develop through to southern and central inland areas where the risk of heavy rainfall leading to flash flooding, damaging winds and small hail are all possible. The risk extends further northeast overnight into Thursday and clears the central and southern inland.
Flash Flood Risk Wednesday
The risk is generally low to moderate with this feature moving through during the afternoon and evening, but where a storm forms, they won't be moving fast, some moderate to heavy rainfall with large accumulation of small hail is possible.
Small Hail Risk Wednesday
The risk of hail is low to moderate with the most robust thunderstorms. But given that we are in cool season, large hail is not considered a high risk, but pea sized hail quite possible with the stronger storms.
Damaging Winds Risk Wednesday
Damaging winds are possible with the more organised multicellular thunderstorms that form, with outflow winds from the heaviest storms up to 100km/h possible.
Thunderstorm Forecast Thursday
Thunderstorms are forecast to be ongoing over the Central Highlands and Coalfields and extend further east into the Northern Wide Bay and through the Capricornia and torwards the Central QLD coast. Heavy rainfall and large accumulations of small hail is possible with damaging winds a lower risk.
Damaging Winds Risk Thursday
Damaging winds are a low risk on Thursday with the upper trough moving throughout the region. A stronger wind profile is forecast to remain offshore the Central QLD coast with the developing low-pressure system. A secondary low-pressure system could bring strong wind fields back to the coast by Friday night into Saturday.
Flash Flood Risk Thursday
Flash flooding is a risk through the Central areas of QLD with a deep moisture profile linking into an upper trough with another trough offshore the east coast with areas of rain and thunderstorms with a higher risk of flash flooding just offshore. The risk of flash flooding contracts to the coast during the evening. Some areas could see 50mm+ in a couple of hours.
Hail Risk Forecast Thursday
There is a low to moderate risk of hail developing with thunderstorms throughout the region identified on Thursday. Large accumulation is possible inland of the coast with slow storm motion. Most of the hail if it forms should be small, with the instability lower in the cooler season.
Rainfall for the event
The latest modelling side by side for the event - you can see the subtle differences in the placement of the low pressure which will shift the rainfall totals depending on which model you want to treat as gospel. This will mean your rainfall forecasts for inland areas into northern NSW will remain low confidence.
The good news for the state is that the severe weather is unlikely to develop along the coast for now, there will be a period of heavy showers and strong winds later Friday with a low drifting parallel to the coast but the impacts strictly coastal.
By next week, the weather is forecast to recover, and a more traditional weather pattern is forecast to unfold with a west to northwest flow set to return.
More coming up in the evening updates - but remain across the radars today through inland areas with storms firing from this afternoon.