The very hot weather that has been experienced in the west in recent days is heading eastwards as the pattern begins to evolve, from that persistent ridge over WA, to now placing it through the south of the nation and then into the southeast over the weekend into next week.

That will allow for conditions to warm up and dry out in the east and southeast, but the west will remain dry, but cool back down towards seasonal values for this time of year. It has almost been climate whiplash over in the west with the cool Spring followed by a very hot December.

The other weather story to watch is that tropical low near Katherine moving east into the Gulf over the coming days bringing heavy rain and strong winds over northern QLD. Flood watches are in place as expected. Flood Warnings are now in place for the Top End.

Storms will continue for parts of inland QLD and extend into pockets of the interior over the coming days, however, the weather is not looking as wet as recent days, so many areas will be going dry.

Lets take a look


Rainfall Next 10 Days

No change to the guidance overnight with the bulk of the wet weather in the process of contracting east through the Top End as the tropical low is absorbed into the northwest flow aloft. The monsoon trough remains north of the nation for much of this week seeing the wet weather just offshore for the bulk of this week, but showers and thunderstorms will float about. For QLD, the heaviest rainfall looks to be now over FNQ with heavy falls and flooding around the Gulf. There may also be flooding over the Lower Burkedin and Herbert if the tropical low heads overhead and then offshore. Models then struggle to place it into the medium term, some send it offshore and some send it south. Low confidence remains in this forecast. The rest of the nation, hit and miss showers and thunderstorms are expected to continue for much of the nation's interior. The west and the south coastal areas mostly dry for now. There is evidence the monsoon may kick into gear again just outside of this period with further tropical low development possible and this leading to better rainfall prognostics.

Thunderstorm Forecast Tuesday

Thunderstorm severity contracting north and east through the nation as the remnant tropical low pushes into QLD. Storms may be heavy with flash flooding and gusty with damaging winds. Thunderstorms continue for much of QLD and will likely to edge south into northern and western NSW and eastern SA. These more isolated with the chance of one or two heavy falls. Dry storms for the west coast possible in WA.

Thunderstorm Forecast Wednesday

Thunderstorms continue for much of northeast QLD with heavy rainfall leading to flash flooding and damaging winds the main risks on Wednesday. A trough sharpening through the western interior of QLD will extend through eastern SA with a few showers and thunderstorms but moisture is limited. Thunderstorms tending more scattered over the NT and into northwest WA with storms heavy in pockets but no severe weather possible. Dry storms with a lightning risk over WA.

Thunderstorm Forecast Thursday

Thunderstorms become more scattered over the north in a monsoonal break scenario, the main forcing remaining offshore, so no severe weather expected. Gusty high based storms over interior may bring damaging winds. Thunderstorms embedded in spiral bands around a tropical low moving east over FNQ may bring areas of flash flooding.

Tropical Depression Formation Risk - This Week - December 28 2021 -January 4 2022

The tropical low that is over the interior of the NT is heading east and is likely to maintain a weak circulation as it heads east. The low may pop off the FNQ coast and this low may deepen further into the medium term.

Excessive Heat - This Week - December 28 2021 -January 4 2022

The excessive heat is expected to spread from west to east throughout this week with a very hot airmass lining up the eastern inland west of the divide over QLD, NSW and VIC through much of SA with a cooling trend for WA.

DATA - Refer to video for more information

12Z Euro - Surface Pressure Pattern and Rainfall Distribution - Next 10 Days

The GFS comparison can be found in the video at the top of the page. The Euro shows the monsoonal break conditions over northern Australia with the trough sitting offshore. A large high over the south will dominate the synoptic pattern for the south and southeast with dry, warm to hot and settled conditions for most of the region. This high will help keep the remnant tropical low over tropical parts of QLD before heading into the Coral Sea. We saw many solutions having heavy rainfall coming south into NSW and much of southern QLD but this looks less likely now, with showery weather expected but not the significant heavy rainfall first thought. The west will see temperatures come down this week over the course of this week with a southerly change expected. The tropics will return from monsoonal break to build up conditions but the emergence of further tropical depressions remains moderate.

12Z Euro - Precipitable Water Values - Next 10 Days

The deep moisture layer is continuing it's journey over northern Australia into QLD with heavy rainfall following that swathe of tropical air. The dry air continues to remain in place for much of the period for southern Australia with high pressure close by leading to that lovely settled Summer weather with hot temperatures over the south, very hot weather in the southwest. The east coast, still humid, the La Nina Summer still going to plan with showers/rain persisting off and on for much of the period, with the heaviest of the moisture content expected over the central and northern parts of QLD. Note in the medium term, the moisture deepens over northern Australia once again with the return of build up conditions.

12Z Euro - Rainfall Accumulation - Next 10 Days

More details in the video

12Z CMC - Rainfall Accumulation - Next 10 Days

More details in the video

12Z GFS - Rainfall Accumulation - Next 10 Days

More details in the video

12Z GFS - Rainfall Accumulation - Next 16 Days

More details in the video - note the resurgence of monsoonal rainfall in the medium term following the drier air in the wake of the low pressure.

12Z Euro - Rainfall Accumulation - Next 15 Days

More details in the video

More weather coming up today and back to the two a day schedule on the national wrap this week and back to state based forecasts very soon - but if anything significant or severe is in the works then dedicated posts will be written. State based forecasts coming up daily from January 10th 2022. Later on, the updated 6 week outlook.

82 views0 comments