Another look at where we stand for the coming week or so over southern and eastern Australia.

Surface Pressure Pattern and rainfall for the next 16 days - Valid Saturday 10th of July 2021.

A fast flow pattern remains the dominant feature next week, but keep an eye on that moisture, it is still there and while it is not in phase in this current run, it is increasingly likely the moisture will play a part in bringing inland rainfall after this 10 day period I analyse below.

Lets start in the east with QLD

The state has dried out in the last 24 hours with high pressure moving in and that is allowing a dry airmass to remain in place for the weekend and into next week.

The high will drift into the east with a northwest to westerly flow developing with warmer weather expected to drift in from the north and west as the state sits mainly to the north of the jet stream. An upper high over the far north will send temperatures above average.

Mid to late week, cloud may increase from the west, with a jet stream cloud band through WA into SA and the southern NT, through NSW and southern QLD. Some light and patchy rainfall is possible with this feature during later Tuesday in the southwest, and spreading throughout Wednesday across southern districts. Another wave will develop later in the week with more light rainfall possible.

Showers may develop along the coast in onshore winds, but light falls away from the Tropical Coast where falls may grade to moderate.

GFS 18Z - Rainfall for the next 10 days - Valid Saturday 10th of July 2021

Rainfall guide again keeps the moisture associated with the cloud band further south towards the NSW border with the fast moving jet stream bringing cloudy skies through southern districts. Fine and clear weather is expected through the remainder of the inland at this stage with that still a low confidence forecast with so much moisture floating around through the northwest during the latter parts of this period.

Rainfall for the next 10 days - Valid Saturday 10th of July 2021.

My forecast reflects the drier period for the inland but also brings in some light precipitation for central areas as well with a risk of the cloud band moving through central areas later in the period, with light falls. Warm temperatures though will be experienced over northern areas of the nation under an upper high, and near seasonal or slightly above seasonal weather for those further south.


GFS 18z run -Rainfall for the next 10 days - Valid Saturday 10th of July 2021.

Can see that rainfall bias on and west of the divide in the winter westerly regime, thanks to the fast moving cold fronts moving through the southern parts of the nation. Moisture derived from the jet stream will also be in play and this could see rainfall increase at times next week, so something to watch as we get closer to each front. First front Tuesday into Wednesday will bring the most widespread rainfall, the second front is colder and will bring rainfall back to the southern half of the state. Dry weather after today expected for much of the coast in the shadow of the Great Dividing Range.

Active weather builds thanks to the westerly wind regime bringing widespread cloud and showers from Tuesday throughout the state. Some of the falls may be moderate along the western slopes of the Great Dividing Range with that rain persisting through until Wednesday afternoon.

Showers may ease temporarily through Thursday before another stronger front moves through on Friday bringing another burst of light to moderate rainfall for inland areas, more likely to impact central and southern parts of the state with a much colder shift unfolding.

Snowfalls will develop for Alpine areas later this week, probably a fraction too warm for the nice snowfalls desperately needed up high with the first system dragging in tropical moisture from the Indian Ocean.

More rainfall exists outside of this period.

Rainfall for the next 10 days - Valid Saturday 10th of July 2021.

Rainfall bias is certainly on the western slopes of the range this week with the heaviest falls along the coast over southeast SA and southwest VIC and along the Alpine Peaks where that precipitation will fall as snow later this week down to 1000m or lower. The coast will turn drier from tomorrow afternoon as the low moves away.

Rainfall for the next 10 days - Valid Saturday 10th of July 2021.

A closer look at the bias over the western side of the divide, these falls may fluctuate a bit as we get better clarity on the moisture plume coming in from the northwest.

Rainfall for the next 10 days - Valid Saturday 10th of July 2021.

A closer look at the southeast where you can see that bias along the western slopes of the divide and the rainfall numbers coming down in the rain shadow zone which will increase tomorrow once we lose the onshore southeast to southerly flow from the coast.

For VIC and SA.

GFS 18z Rainfall for the next 10 days - Valid Saturday 10th of July 2021.

Note the moisture is increasing gradually over inland areas, with some banding of 20-30mm showing up under that battle ground cloud band. Love to see this become more widespread with one of the fronts passing through this week. Moderate coastal falls are anticipated this week.

Showers developing from the west later Sunday with a weakening cold front, with the chance of a thunderstorm for coastal parts into the southeast of SA. Some moderate falls are possible about the southeast of SA and into southwest VIC. Light falls may extend into the remainder of the western districts as the trough moves onshore.

For the remainder it should remain dry with cloud thickening during the afternoon and the evening.

Monday, cloud with scattered showers throughout most districts with a weakening front. Some light falls expected. Low risk of a thunderstorm along the divide as that trough and front weakens over the state. Showers will clear out of SA with a weak ridge to follow.

Monday night, showers and windy weather over western SA begins to move closer to the YP and into the Gulf region with rain areas developing as the front encounters more energy and moisture over central and eastern SA. Moderate rainfall is possible about the YP into the Adelaide region and then the eastern areas overnight into Tuesday before moving into Victoria and NSW. Showers will follow over much of southern SA during Tuesday more frequent in areas exposed to a westerly.

Into Victoria Tuesday a front approaches later with showers increasing from the west with the chance of a thunderstorm. Showers turning to areas of rain with moderate falls developing over the state as the front moves through but there will be pockets of South Central VIC that may be in the rain shadow of the dividing range. But reasonable falls for the northern slopes and across the northeast. Showers to follow the rain band over the south with local thunder possible.

Rain moves out Wednesday into NSW with showers continuing, more widespread about the ranges and in the southwest in northwest winds. Some thunder is possible about the southwest later with another shortwave passing through. Similar conditions expected Thursday.

A stronger front moves through the region Friday into the weekend with a cold southwesterly change to follow. Rain developing late Friday from the west with moderate falls then tending to showers, with hail and thunder. Strong and gusty southwest winds developing. Snowfalls down under 1000m is possible. Rainfall moderate at times through southern SA into southern VIC. Heavier falls through W Gippsland and E Central areas in a southwest flow in a week's time is possible.

Showery and cold weather persists into the weekend in southwest winds.

Rainfall for the next 10 days - Valid Saturday 10th of July 2021.

Rainfall is the traditional winter spread for the state with the heaviest falls for anyone exposed to that westerly flow. The rainfall will increase Tuesday and again Friday state wide with the passage of the fronts but the wettest weather expected along the divide, northeast ranges and southwest districts where the rainfall will be more persistent. Very wet weather for western Tasmania where some locations could clear 200mm for the week.

Rainfall for the next 10 days - Valid Saturday 10th of July 2021.

Rainfall gradient largely unchanged which is good, but the numbers will continue to creep up and go down with the frontal weather moving through. Moisture is hard to pin down still. But positive signs for most areas to see at least 10mm.

Rainfall for the next 10 days - Valid Saturday 10th of July 2021.

A closer look at Melbourne and the western suburbs into the Ballan and Meredith regions could be rainshadowed in the first system but better rainfall comes with the shortwaves that follow and later in the week into next weekend once the flow turns more unstable west and then southwesterly.

More details to come.

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