NATIONAL WEATHER PICTURE - PM EDITION - WEDNESDAY JULY 7TH 2021.

Headlines


  • Weather easing for a brief period over southwest WA but more wild weather is on the way.

  • Eastern Inland rainfall event likely to spark half to one months worth of rainfall for many locations through extreme southern QLD and more likely the northern inland of NSW.

  • Another cold night on the way for the eastern and southern inland with a freeze possible for the southeast of NSW.

  • Rain comes back through southern Australia next week and the signals are gradually improving for inland areas of the coast.

It has been a wild few days of weather through the southwest of the nation with significant winter time weather of the region. This is likely to come back on Friday with the next set of strong fronts to move throughout the region delivering more severe weather potential.


The eastern inland expecting an upper trough combining with a surface trough to trigger widespread rainfall from later Thursday, as moisture is dragged into this system from the north. Moderate to heavy rainfall possible with thunderstorms. The quick fire system productive, but moving through at pace Friday.


Another cold night is on the cards for inland parts of QLD, NSW, ACT, northern VIC and the southern NT with high pressure still in the region. Conditions will begin to moderate in terms of cold nights from Friday with a pressure trough moving over the east with more wind and cloud about.


Rainfall chances coming up for southern Australia including inland parts, it may be patchy but over a number of days, could start to accumulate to 10-20mm for many locations from Tuesday.


National Satellite Picture - Valid 5pm Wednesday 7th of July 2021.

Mainly clear satellite for a lot of the continent thanks to high pressure over the southeast driving settled conditions. Fair weather high cloud over parts of SA developing along strong winds aloft and also responding to an upper trough approaching from WA. Fair weather cirrus sailing through on the jet stream over QLD. The main feature over the southwest is that broad long wave trough that has peaked and now sliding to the southeast due to ridging over the east.

Cold front with cold air aloft passing through the southern parts of WA today, with the flow stabalising this afternoon over the west coast as a weak ridge approaches. The showers, still gusty with small hail and thunder about the southern coast will ease tonight and be offshore by morning. Tomorrow will be a drier day for the inland with a ridge passing over central areas.

Temperatures - Valid 5pm Wednesday 7th of July 2021

Much warmer today through the southern and southeastern areas. Nice tongue of warmer air coming through the eastern parts of WA and into SA with a northwesterly flow developing ahead of that strong front that is moving east and weakening tonight. Fine and seasonal over much of the east, a little cooler than average but nothing outrageous. Seasonal over the north.

Cold back through the southwest with a deep layer of cold southwest wind moving east today. The temperatures will recover a little tomorrow but this does continue the below average temperatures for the SWLD. North and east of the cold pool. temperatures are near to above average.

After a freezing start, it has recovered nicely by mid afternoon with a good supply of sunshine, just some high cloud drifting through at about 40000ft. Temperatures will plunge once the sun goes down again with another frost and freeze possible over the ranges of NSW and lighter frosts back into QLD and VIC.

Radar - Valid 5pm Wednesday 7th of July 2021

Showers now easing over the west coast with the airmass stabalising thanks to the high edging in from the west and the southwest flow moderating and tending more stable northwesterly tonight. Showers more frequent about the south coast with local hail and thunder contracting east and offshore later tonight.

Rainfall for the next 10 days - Valid Wednesday 7th of July 2021

Rainfall becoming more widespread over the northeast inland and extending to the coast now, thanks to the low that develops on the trough over NSW during Friday, before clearing offshore Saturday. The rainfall continues on the southwest with the frontal barrage continuing, with locally heavy falls continuing. Showers increasing over the southern coast line of SA and through VIC, TAS and into southern NSW from Tuesday onwards with an unstable westerly wind regime and frontal weather coming eastwards.

00z GFS Rainfall - Next 10 days - Valid Wednesday 7th of July 2021

Rain breaks out over inland NSW and QLD tomorrow with moderate falls there. The heavy rainfall continues over southwest WA. Over the southern coastline, the colours are increasing, that means more rainfall chances from Sunday and indeed for most areas from Tuesday with the fast flow pattern sending in front after front after front. Can moisture get involved? That is the question as we watch the Indian Ocean over coming days.

00z Euro Rainfall - Next 10 days - Valid Wednesday 7th of July 2021

Rainfall numbers picking up for the northeast of NSW and extending to the coast with a low forming offshore, but it will move away by Saturday afternoon. Rainfall continues for the southwest of the nation for the coming 10 days. That rainfall focus is moving towards the southern and eastern areas of the nation mid to late next week with persistent falls and gusty cold westerly winds. The eastern inland will dry out with a dry warm westerly flow.

00z CMC Rainfall - Next 10 days - Valid Wednesday 7th of July 2021

Rainfall not as heavy for the northeastern inland of NSW and southern QLD with the CMC run but is equally as widespread, this model develops the low offshore NSW, rather than on land. Showers continues for the southwest of the nation with moderate to heavy falls and showers increasing for the southern coastline and increasing over the southeast inland over Australia mid week onwards.

Model Discussion and Analysis - Valid Wednesday 7th of July 2021


00z GFS Upper flow pattern at 500mb/18000ft

00z GFS Surface pressure pattern with rainfall


Thursday 8th of July 2021

Large upper trough passing through from WA into SA with cloud increasing and maybe some cooler air drifting through. The main dynamics for rainfall lay west of a high over inland NSW and QLD with a surface trough. A weak ridge coming into southwest WA with a temporary break in the wintry weather.

Cold front that is currently over southern WA is weakening on approach to central with little moisture to work with, more clouds expected than rainfall. Note a dip in the isobars over QLD, that will be the focus for rainfall and storms breaking out later Thursday with moisture surging into this feature and the feature invigorated by the upper trough passing through SA during the day. Fine weather back over WA with a weakening southwest flow thanks to a ridge. And fine weather elsewhere after a cold start in the southeast.

And just like that, the trough responds to the moisture and the instability arriving through SA and into western NSW and we have rainfall breaking out over the QLD and drifting into NSW with thunderstorms possible. The main surface front is lagging well behind the trough and producing isolated showers for southern SA. The showers continue for mainly coastal areas of WA but the moderate weather continues through much of Thursday.

Friday 9th of July 2021

Come Thursday night into Friday, the rain could be heavy at times over the northern inland of NSW and southern QLD with a low forming on the trough and racing off to the southeast. This could deliver another month of rainfall to some spots in northern NSW and a half a months worth of rainfall in southern QLD. A weakening front slowly moving south of Adelaide may squeeze a few showers. Another front approaching WA will help to increase showers for the southwest of the state with strong to gale force winds developing once again. Fine weather every else.

Saturday 10th of July 2021

A low moves offshore the NSW coast with rainfall easing over the inland and contracting to the coast. Some of the showers with the wrap into the coast with moderate to heavy falls possible. The showers will clear eastwards during the day. High pressure will take over the southeast once again with a weak ridge redeveloping. A strong cold front delivers a band of rainfall overnight Friday into Saturday morning in WA with cold and showery weather to follow. That front again falling apart on the approach to SA with the ridge weakening the feature.

Sunday 11th of July 2021

Front weakening over the Bight will get a shot of cold air injected into it from the southwest and may help to spawn another band of showers or patchy rainfall for the YP, KI and Adelaide Metro through the day on Sunday before that activity moves into the southeast districts, the main flow of rainfall will be northwest to southeast, so it will not push inland far. Fine weather returns to the west coast with a new high. Low pressure moves away from the east coast with improving conditions. And fine everywhere else, the temperatures well above average over the NT and northern WA with high fire dangers.

Monday 12th of July 2021

Showers developing for southeast SA and western VIC with a slow moving low pressure system and cold front. Cloud increasing throughout the southeast but fine weather prevailing. Showers may develop along parts of the QLD coast with weak wind convergence. Showers and rain developing for the west coast again, with yet another strong front, this will be front number 7 in the sequence, bringing more severe weather risks. It may also drag in moisture from the Indian Ocean bulking up the rainfall along the front.

Areas of rain pushing through western and central VIC as a trough moves through, the main dynamics weakening during Monday afternoon and evening. Cloud increasing further over southern NSW with patchy rainfall at night. Rain and strong winds for southwest WA tending to squally showers with small hail and thunder with a low deepening offshore. Fine weather returns back to SA later Monday with a ridge passing through. Temperatures remain well above average over the north.

Tuesday 13th of July 2021

A band of rain developing through the western interior spreading rapidly via the jet stream into western SA with a fast moving front moving into western SA. Cloud increasing over southern Australia with showers/rainfall developing from the west. A warm airmass over the southeast with a gusty northwesterly wind, reaching gale force about SA later. Showers ending over the southeast of NSW with a trough moving offshore. Still wet and blustery over in southwest WA with another front approaching. Fine and hot over the north and dry in the eastern inland.

A broad band of rain moving through SA with light to moderate falls during Tuesday. That rainfall arriving Tuesday afternoon in eastern SA and spreading into VIC and NSW later in the day or at night. Windy with showers continuing for SWLD of WA with well below average temperatures with a gusty southwesterly flow continuing.

Wednesday 14th of July 2021

Long wave advancing from WA into SA with a lot more gusto, this system not losing as much strength as the previous systems. This trough will also link into moisture and drag an organised batch of wet and wintry weather into the south and east. Ridging over the east lifting off and another upper ridge over the west coast.

A week from today and the signal remains strong for a band of rain with moderate falls passing through southern NSW and VIC. Showery air to follow for SA and WA with 3 fronts embedded in the unstable flow, the strongest front sitting back west of WA again and passing through the region later. A weak area of high pressure over QLD keeping the north and east mostly dry but cloud increasing over the central interior may see patchy rainfall break out.

Thursday 15th of July 2021

Very weak winter high pressure over the centre of the nation, fast moving fronts over the southern half of the nation bringing windy, showery weather to all the coastal areas on Thursday. A strong cold front brings widespread showers with a few heavy falls over southwest WA. Another moderate front brings showers overnight Wednesday into Thursday for SA and into VIC and southern NSW on Thursday. Dry and hot over the north of the nation with elevated fire dangers. Fine over the eastern inland with temperatures possibly above average.

Friday 16th of July 2021

Strong front continuing to run along the southern coast of Australia bringing strong winds and showery weather to SA later in the day. A weak ridge over the east clears the weather early during Friday after a showery Thursday. Showers ease over WA with another high passing to the north through central WA. Fine and hot over the north with a slack pressure pattern and an upper high.

Saturday 17th of July 2021

It takes til next Saturday to get one of the long waves passing through the southeast with a significant westerly burst ongoing with fast moving waves continuing to push through. A broad upper high over the north keeping the temperatures hot and above average. Another long wave approaching WA later brings the next batch of severe weather potential.

A deep low with wintry weather over the southeast with moderate rainfall possible in southeast SA, VIC and TAS, with snowfalls about the Alpine areas continuing. A high over WA clearing the weather briefly over the southwest but another wave of low pressure offshore will increase cloud later and that may bring a large band of rainfall thanks to the moisture feeding into this feature from the northwest. Fine and hot over the north and warm and dry over the eastern inland in westerly winds.


Need more weather information? Email me at karllijnders@weathermatters.org for tailored forecasting solutions.

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