The warm and muggy days and oppressive nights are here to stay with only limited showers and thunderstorms across the state, mainly in the west for the coming few days. Along the coast, you may see a few showers in onshore winds, and in between, through much of the state, things looking fairly settled with high humidity and partly cloudy skies until mid week.

The trough from SA will eventually spill eastwards into our state and this will be the focus of more orgnaised showers and thunderstorms throughout the state, especially on and west of the divide through central and southern areas. As mentioned throughout the past day, this is where the severe weather risks will run higher to end the week with a heavy rainfall leading to flash flooding the main concern.

Now into the weekend, the trough may progress a little further east but some other models are suggesting that the trough will stall out over central and northern inland NSW leaving the coast mainly dry with onshore winds and a few showers here and there with high humidity and only the very far south getting into a drier airmass with less rainfall. The placement of the trough still up in the air, so your forecasts will move around.

Finally, the far northwest corner need to pay attention to the rainfall forecasts through northeast SA and the southeast NT, some of that heavy rainfall may creep into the northwest bringing the chance of flooding.

Lets take a look


Rainfall Next 10 Days

Rainfall remains uneven in distribution with mainly afternoon and evening scattered showers and thunderstorms forecast through this period. The better coverage of thunderstorms will be over the western and central areas of the state to begin with then spreading through the southern inland and towards the ACT with that coverage likely to stall out over the weekend. Severe thunderstorms are possible with heavy rainfall leading to flash flooding the theme of Summer so far, continuing throughout the week. The weather is expected to remain humid and unsettled for the best part of the next 10 days for northern areas with that storm risk continuing. Weak signals do exist for easterly winds to turn more unstable northeasterly into the end of the run increasing rainfall along the coast, but I am not so sure on that just yet.

Thunderstorm Forecast Tuesday

Thunderstorms will remain a feature through western and northwestern areas of the state with a trough meandering through towards the east. Thunderstorms may produce heavy rainfall leading to flash flooding and riverine flooding in some locations. Flood warnings are in force for northwest areas of the state. There may be a few thunderstorms in pockets elsewhere throughout the state, with the greater risk over the ranges and in the southeast Alpine areas where topography will aid development. Thunderstorms are less likely to be severe but the rainfall could still be heavy where they form

Flash Flood Risk Tuesday Afternoon

Flash Flooding is a low risk across a large chunk of the state but where thunderstorms have been occurring throughout areas of the north and west, flash flooding may quickly develop in areas that have seen rainfall in recent days.

Severe Weather Potential - Wednesday through Saturday

The trough will slowly move eastwards from SA through NSW with a band of very unstable air expected to be in place for much of inland NSW from Wednesday and persisting through the weekend. The atmosphere supportive of flash flooding and severe thunderstorms, the coverage at this time not as widespread as SA in recent days but the risk is there. Also for far northwest areas, keep an eye on that heavy rainfall potential through northeast SA and into the southeast NT, as that may begin to creep further southeast through this week lifting flood risks. Finally the flood risk over the north is running high with spill over from the heavy rainfall coming downstream.

DATA - Refer to video for more details relating to the daily breakdown and what you can expect.

00Z GFS - Surface Pressure Pattern and Rainfall Distribution - Next 16 Days

The pattern remains largely unchanged. As mentioned in the video, the elements to watch in the short term, the monsoon trough over the northern parts of the nation and how does that then interact with the inland trough over SA and the NT this week? That may produce significant flooding issues. The other element is the severe weather risk covered off for SA, VIC, NSW, ACT and QLD over the coming days with the trough slowly working it's way through very moist air. The west you stay fairly similar to what you have now, temperatures are expected to surge back into the 40s over the SWLD. In the medium term, watch the monsoon trough for further rainfall chances nationwide. Does the high pressure system ridge in further south allowing for more easterly winds to dominate the nation or do we get dry air developing with the ridge sitting higher over southern parts of the nation? These questions will be answered throughout this week with some luck.

00Z GFS - Precipitable Water Values - Next 16 Days

A very deep moisture profile over the nation with heavy rainfall and thunderstorms about many areas. I will mention watch the medium term, we could see an abating of the high humidity and rainfall chances over the nation with the monsoon trough being kicked back northwards towards the tropical north. Could increase the cyclone risk over northern parts of the nation into early February.

00Z GFS - Rainfall Accumulation - Next 10 Days

Refer to video for further information

00Z CMC - Rainfall Accumulation - Next 10 Days

Refer to video for further information

00Z GFS - Rainfall Accumulation - Next 16 Days

Refer to video for further information

A closer look in - the rainfall guide remains low confidence at this time. But thunderstorms will be driving the very heavy rainfall potential throughout the state.

More coming up with the wrap on all things rainfall and the modelling tonight to see whether we can get some clarity on the severe weather in the short term and the monsoon trough driving the heavy rainfall event for the north and central areas.

78 views0 comments