The above average rainfall continues for large areas of the east of the country and the dry weather is ongoing for the west, the south too, feeling the below average rainfall while the north sees a drying out of the pattern leading to more seasonal conditions.
The heavy rainfall and the chance of severe weather is expected to continue throughout tonight and Sunday with the chance of flash and riverine flooding the main concern.
How long the rain event continues to hold on over in the east, will determine the spread of the rainfall and length of the rainfall event for QLD and NSW, but also this has downstream impacts, where the frontal weather can be suppressed by the presence of easterly winds across the nation.
This pattern will eventually break down, and frontal weather looks likely to resume over the southwest and west of the nation thanks to the high moving over the east and the long wave trough well offshore WA bringing back frontal weather to the forecast with light to moderate rainfall next weekend and beyond.
Looking more seasonal in terms of rainfall and temperatures as we move through the second week of July with frontal weather resuming, with high pressure retreating northwards back over the interior with stable conditions. How far north the high-pressure belt moves will be dependent on the SAM phase and whether it can move back to negative thresholds.
Drier air and cooler weather over northern Australia will begin to ease through this period with humidity possibly returning to coastal areas with showers developing.
AREAS TO WATCH
The SAM is of interest for this week ahead, we know that it has been positive, and we have seen that play out with drier weather over the southwest and south of the nation. The positive SAM phase has led to the well above average rainfall across northern and eastern Australia.
Indian Ocean moisture is lurking about through the latter part of next week and into the weekend with widespread falls possible under broad cloud bands, whether they can be in phase in relation to frontal boundaries passing through remains to be seen.
Rainfall Next 10 Days
The heavy rainfall continues tonight for large sections of the east coast with the potential for severe weather to continue right into early next week. Conditions may be supportive of near record rainfall for some sections of the east coast. The rain turns to showers over the coastal areas from Tuesday before clearing through the week. Once we lose the easterly wind bias over the east of the country which is leading to drier weather over southern and western areas with high pressure stuck over the region, this will start to see the pattern move along with showers gradually returning to southwestern and western areas of the country and clearing the east coast as a more traditional Winter pattern develops.
Rain and thunderstorms continuing to move slowly towards the east with a surface trough, but an upper-level low will catch up to it during early next week with a secondary burst of widespread rainfall and heavy falls possible for the coastal areas between Proserpine and the Sunshine Coast. Some areas could see 200mm. The rainfall clearing east and easing before we see a more typical weather pattern unfold from later in the week with drier air returning with ridging.
Severe weather with torrential rainfall is expected to feature through the Central Coast down into the Wide Bay and maybe the Sunshine Coast.
NEW SOUTH WALES AND VICTORIA
The rainfall over the east coast of NSW will continue to be at decile 10 levels over the coming 2 days for areas along the Central Coast and points southwards to Batemans Bay. Inland areas can expect to see widespread showers and thunder tonight with small hail but the rainfall more hit and miss as advertised which is frustrating the many spreading fertiliser to get things moving along, but with the moisture in place and low pressure wafting around it will be a very good effort to avoid at least 5-10mm at least through this period. The showers clear the east coast from later in the new week with showers redeveloping for southeastern areas from later next week with the next set of cold fronts passing by.
The bullseye for heavy rainfall is still over the eastern seaboard across heavily populated areas including Sydney and Wollongong.
Dry for much of this week as the ridging and the neutral SAM phase work in tandem to bring a dry bias for the Ag Areas. As pointed out, we are sitting in an area of bad luck which is where the Goyder’s Line is in full force, with much of the rainfall this week coming (mainly through the weekend into next week) south and east of this area which is normal. With the anomalous weather pattern over the north and east, it has disrupted the westerly flow, and this is going to lead to further drier weather for a while which is frustrating but the reality at the moment.
Also, frustrating has been the drier bias over in WA Ag Areas where the region has been sitting under persistent ridging for a week and that is likely to continue into next week wtih areas likely to be impact by frontal weather from Tuesday but more likely as we move through to the end of the working week and following weekend where rainfall totals could be moderate and start to make up for the deficit left over from this dry spell. The weather looking to be more traditional as we move into mid-month.
July 10th-17th 2022
With a cooler and more stable nation, many areas over the interior return to more seasonal weather expectations and the frontal weather is likely more muted through this period as well, leading to frontal weather returning over the south but not with the high intensity that can accompany July.
It is going to take a bit of time for the inland to recover from this anomalous rainfall event with temperatures below average for a while. The temperatures will be near seasonal over in the far northwest and along the east coast but it does look to be a long period of below average temperatures at this time into mid July.
More coming up on Sunday morning - have a great evening.