NATIONAL WEATHER PICTURE - AM EDITION - MONDAY 21ST OF JUNE 2021

Headlines


  • Heavy rain and strong winds for WA this morning, contracting east and south throughout today.

  • Warming up after a cold start in the east.

  • Strong winds and cloud thickening for SA.

  • Rain still expected to spread east over this week.

A major weather system is continuing to drive cold, showery and windy weather to the southwest of WA this morning, easily the coldest air the region has seen so far this year.

Snowfalls are expected over the Stirling Ranges today and tonight as the cold airmass moves through.


A broad band of rain and some thunderstorms is moving through the inland, expected to move east today, bringing light to moderate rainfall to the central and southern interior. It will reach the east later tonight.


A cold start in the east with patchy frost and fog about. A nice warm up today with a northwest wind freshening over SA and wind veering into the north over Victoria finally giving some seasonal conditions.


The showers along the east coast hanging on today with another wave of low pressure moving through the upper atmosphere, combining with onshore easterly winds. Some moderate falls are still expected for the region.


Rain is anticipated to move across the nation this week, with follow up rainfall looking a strong possibility as we track into this coming week once again from the west.


National Satellite Picture - Monday 21st of June 2021

Broad area of cloud developing ahead of a strong cold front with a deep low forming near WA with widespread rain and a few storms. Another cold airmass to the south of WA with polar weather is staying offshore for now. Fine and clear elsewhere though a trough over the east coast still producing showers.

A broad area of cloud has developed in response to the low forming over the SWLD with areas of rain and a few thunderstorms with cold weather over the southwest. Widespread rainfall moving through the interior. Clear over the northwest with dry skies. Very cold speckled air over the southwest with local hail and thunderstorms with snowfalls developing over the Stirling Ranges.

Temperatures - Monday 21st of June 2021 Valid 6am EST.

A cold airmass over the southwest driving showers and strong winds and well below average temperatures. A cold start in the east with a high over the region. Local frost, some severe through southeast NSW on Monday morning, but with clear skies and little fog, the day will warm fairly steadily for Winter Solstice.

A closer look at temperatures overnight and we can see temperatures below 0 in the southeast of NSW, the coldest being -6C at Cooma this morning, not a freeze but a significant dry frost about the region, but again will warm up nicely.

Radar - Monday 21st of June 2021 Valid at 6am EST

Widespread rain currently underway though WA and expected to thicken up further through the Pilbara throughout the interior as a trough and front moves east. A deepening low over the southwest has caused heavy rainfall and strong winds with further showers, some heavy with hail, thunderstorms and snowfalls this evening.

24hr Rainfall through to June 20th - Heavy rainfall through the southwest with 50-60mm around Mandurah and scattered 20-50mm throughout the SWLD. Lighter falls did start move inland.

20hr rainfall to 21st of June 2021 - Heavy rainfall about the south coast with scattered 50-70mm with the top fall of 110mm at Denmark with some flash flooding being reported. Light rainfall developing over the Pilbara should increase today.

Rainfall for the next 10 days - Valid Monday 21st of June 2021

Widespread rainfall in the west continuing to move eastwards with a front and low. That rainfall will move into SA during tomorrow and most east mid week, some of the rainfall could turn patchy as the low rotates through, but then will link up with more moisture over the east to reinvigorate once again for NSW and QLD. Another large system is expected this weekend in WA moving east once again.

GFS Rainfall for the next 10 days - 12z run valid Monday 21st of June 2021

CMC Rainfall for the next 10 days - 12z run valid Monday 21st of June 2021

Euro Rainfall for the next 10 days - 12z run valid Monday 21st of June 2021

Model Discussion and Analysis


GFS 12z Run - 500mb/18000ft flow pattern - Valid Monday 21st of June 2021

GFS 12z run - Surface Pressure Pattern/Rainfall distribution - Valid Monday 21st of June 2021


Monday 21st of June 2021

Deep upper low over in the west, upper ridge in the east with a high amplitude pattern underway with a gusty flow developing. Upper trough over QLD keeping the unsettled weather over the east coast. High pressure over the north.

Widespread rainfall and a few thunderstorms through WA with moderate to heavy falls across the state, reaching the eastern border later. Bitterly cold air will see showers bring hail and thunder as well as snowfalls to the Stirling Ranges. Showers developing over the east coast with an upper trough moving through combining with onshore winds. A strong high lead to that frosty start over the southeast will lead to a sunny mild day with seasonal temperatures.

Tuesday 22nd of June 2021

Deep upper low over the Bight driving severe weather for southern coastal areas of WA and that activity beginning to move into SA. A strong upper high over the southeast leading to another frosty cold night but settled conditions. Upper trough lifting out into the Coral Sea.

Widespread showers and patchy rainfall moving east with a strong cold front pushing into SA, though the front starting to lose the moisture source from the northwest and the dynamic forcing with the low also hanging back meaning rainfall rates could drop off a bit over SA, but still rainfall is expected. Strong and gusty winds over the southern parts of WA with cold weather continuing. High pressure over the southeast with settled weather continuing.

Wednesday 23rd of June 2021

Strong upper low over the Bight slowly moving east, cut off from the westerly wind regime over this period. Strong upper high moving east of NSW but controlling weather in the east for another day. A new upper ridge over the southwest will clear skies and bring cold nights to the inland.

Deep surface low which is vertically stacked, controlling weather over the southern parts of the nation. Rain areas and strong winds moving through SA into NSW and southern QLD with moderate falls developing as the band encounters more moisture over the region. Rain statewide over VIC and TAS with cold westerly winds developing later. Showers increasing over SA with hail and thunder later. Fine over the southwest with a cold start. A few showers possible about the east coast with weak onshore winds.

Thursday 24th of June 2021

Deep upper low starting to weaken as it passes into the southeast with cold wintry weather developing. Upper high over the east with settled weather moving eastwards. Another strong upper high over the southwest with more settled weather with light winds and cold nights.

Widespread rainfall through NSW and southern QLD with some moderate falls over the Great Dividing Range extending through NSW down into northeast VIC. A low weakening over southwest VIC will bring the risk of showers, hail and thunder to the region and back into southeast SA with a few moderate falls. Fine over the southwest with high pressure strengthening. Humid over the northern parts of the country with showers developing overnight and during the mornings.

Friday 25th of June 2021

Deep upper low opening up into a trough and moving east, with a strong upper high over NZ continuing to hold firm over the Tasman. A flat ridge back over southwest WA with a zonal flow to bring fine weather and height slowly coming down over the northern parts of Australia.

Widespread rain continuing through QLD and moving eastwards towards the coast with mainly light falls. Patchy rainfall extending back through to the Top End with cloudy skies and humid weather, ahead of a southeast surge later. A trough through the southeast bringing scattered showers with conditions clearing back over SA with a high pressure ridge beginning to build. A weak cold front to bring coastal showers over SWLD of WA.

Saturday 26th of June 2021

A flat ridge beginning to build over much of the southern parts of Australia with a zonal flow. Strong upper high over the Tasman Sea but the pressure is rather weak so it is a dry picture in the upper levels with the only wave of note south of Tasmania with a front extending north of this area.

A front connected to a long wave well south of Tasmania riding through to the south of high pressure bringing showers to southeast SA, southwest VIC and Tasmania. Fine weather through much of the nation under high pressure.

Sunday 27th of June 2021

Ridge building over much of the nation with heights coming up. A strong long wave approaching WA with the next wave of low pressure bringing windy weather and another burst of wintry weather.

Very weak trough over the southeast in the wake of a front moving through to the southeast with showers clearing. A few showers in onshore winds over QLD with light falls. Showers increasing over the southwest with a front marching towards the coast. Moderate to heavy falls possible with this feature.

Wednesday 30th of June 2021

High amplitude pattern still being signaled by the models showing a deep upper trough and long wave over the west and a strong upper ridge over NZ. That will set the stage for a series of vigorous fronts to move east through southern Australia with a zonal flow keeping the nation dry.

Strong and gusty winds over southern Australia with a series of strong cold fronts rolling through the southern parts of Australia. A flat ridge over much of the nation with a subtropical ridge in place keeping skies mostly clear and temperatures near seasonal. Another cloud band may develop over northwest Australia with the strong wave action to the south, which may bring back inland rainfall to kick off July.


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