The weather is starting to shift nationally, after what has been an absolute wash of weather for many locations. Inland QLD has been sitting under unsettled skies for the best part of the last 3 weeks with heavy rainfall leading to flash flooding in many locations. That is forecast to continue during Thursday with the peak of the severe weather expected tomorrow and Friday for southeast and southern areas, then into Central areas through the weekend.
A trough is expected to stall out over the southeast during the latter part of the week into the weekend and then lift up into central coastal areas with heavy falls about the region.
The trough will weaken and then onshore winds will resume with the high over the southeast with light to moderate showers to continue for most of next week.
Across the inland, dry weather is expected to resume for a number of days with a nice flush of dry air moving through the nation, and that will be with us through next week. This will assist with the flood levels coming down over inland river systems.
Over the tropics, the monsoon trough will linger and this could spawn some tropical lows next week which may enhance rainfall in some areas. The MJO is expected to be on the approach through northern Australia which could see rainfall increasing again later next week.
Lets take a look
Rainfall Next 10 Days
Rainfall is extensive and heavy in parts tonight and again during Thursday with a high to very high chance of flash flooding with thunderstorms continuing for the coming 24hrs. The rainfall will begin to ease from west to east throughout Thursday and then clear Friday. Anywhere north and east of a trough is expected to see persistent humidity and showery weather through the weekend, this likely reserved for areas north of about Longreach to Bundaberg. Showers will continue along the east coast with onshore winds, but falls will remain light. Inland areas west of the divide should be dry with easterly winds and seasonal temperatures. Keep watch on the tropical low potential over northern Australia in the coming days. I will have more details on that more likely over the weekend.
Thunderstorm Forecast Thursday
Widespread rain and thunderstorms are expected from the northwest through to the southeast with a dry line clearing the storm risk during the day from southwest to northeast. Heavy rainfall leading to flash flooding the main concern tonight and Thursday. The risk will be mainly over areas between Longreach and Bundaberg on Friday.
Flash Flood Risk Thursday
The flash flood risk remains very high tonight and again through Thursday but the thunderstorm coverage and flash flood risk will contract northwards through the day and ease by night time over the central areas. The flash flood risk may be ongoing from later today and overnight through Thursday morning over the southern and southeast districts.
DATA - Refer to video for further analysis and the daily breakdown
00Z GFS - Surface Pressure Pattern and Rainfall Distribution - Next 16 Days
The latest guidance as mentioned is low confidence, this is too dry out the south and central interior, which is a very high chance of occurring. The wet weather moves to the north and east of the nation with prevailing onshore winds driving the wet weather and troughs over the east and north, driving the heavier rainfall. The wettest part of the nation will be over the Top End and Cape York as well as parts of the NSW and QLD coasts. The weather warming up and remaining dry into next week over WA, SA, VIC and TAS. A gorgeous weekend on the way for many areas with a chance to dry out with low humidity and warming temperatures. The weather will start to turn over WA into the new week with a rare Summer front clipping the southern coast with a few showers and brisk southwest winds. The monsoon trough up north may continue to drive tropical downpours, but also may form tropical depressions over the north of WA, NT and QLD. So will be watching closely as this may support wet weather returning to large parts of the nation as we edge into the second half of the month.
00Z GFS - Precipitable Water Values - Next 16 Days
The moisture is continuing to move northwards with the monsoon trough being pushed north through to the tropics. A high over the south is sending that drier southerly flow through the south, central and eastern inland of the nation with that likely to be with us for about a week so low rainfall and thunderstorm coverage. The weather over the north will likely remain the most active across the nation. The wildcard system to watch in the short term will be the moisture coming in ahead of change over southern Australia next week and whether that feeds off moisture as it runs into the northeast to easterly flow over the east as well.
00Z GFS - Rainfall Accumulation - Next 10 Days
Refer to video for more information
00Z CMC - Rainfall Accumulation - Next 10 Days
Refer to video for more information - this is the more likely solution - I think there will be influence from the northern tropics which look to be active.
00Z GFS - Rainfall Accumulation - Next 16 Days
Refer to video for more information
More details coming up from 8am EDT.