NATIONAL WEATHER PICTURE - PM EDITION - MONDAY 21ST OF JUNE 2021.

Headlines


  • Cold and wintry over the southwest of WA with widespread showers, hail and thunder and snowfalls over the Stirling Ranges.

  • Broad cloud band bringing rain periods to inland WA and this is moving further east overnight to be in western SA on Tuesday.

  • Widespread rainfall expected over the southern and eastern states with the moisture spreading east and the trough running into more moisture over the eastern areas.

  • Another wave of wet weather expected over the southwest of WA this weekend.

An active day of weather across Western Australia as expected with a deep upper low and front contracting eastwards through the state. Widespread showers and thunderstorms have been active today with a polar airmass bringing widespread winter weather issues, with snowfalls observed over the higher parts of the Stirling Ranges.


Areas of rain have erupted along the trough in response to a moisture plume that has been drawn in via northwest winds in the upper atmosphere, the trough acting as the lifting mechanism to produce widespread rainfall and colder temperatures over the outback. This band of rainfall will persist tonight and into Tuesday contracting east, with brighter weather returning later.


Rainfall developing over western SA with a strong and gusty northerly flow on Tuesday, with quite a few reasonable falls about the Pastoral districts as the front moves closer. Some chance of thunder about the Eucla and Nullarbor over the coming 24 hours with small hail possible. Winds may become gale force with damaging wind gusts possible.


Another wave of wet weather will sweep into the west coast during the weekend as this lead system moves out of the east of the nation. That next wave could bring another round of severe weather to SWLD of WA.


National Satellite Imagery - Valid Monday June 21st 2021.

Large scale cloud band now underway through WA bringing widespread rainfall and a handful of thunderstorms. Cold and showery through the southwest of the nation with a deep upper low moving east and a surface low deepening offshore the south coast. A trough on the east coast with showers easing this afternoon, otherwise clear elsewhere with light winds.

An impressive cloud band has evolved this afternoon over inland WA with light to moderate rainfall underway. A cold airmass over parts of SWLD producing showers, local hail and thunder throughout the region. Snow has been observed over parts of the Stirling Ranges in this cold and gusty airstream.

Temperatures - Valid Monday June 21st 2021

Fine with more humidity over the north today with a slack easterly. Fine and mild over the southeast with clear skies for the most part. The main cold air is back through the southwest with the coldest day of the year.

The weather is very cold over the southwest with temperatures easily the coldest of the year for the west and southwestern areas of the state. Perth only 14C today but feeling more like 5C with high wind chill. Snow has been reported over the Stirling Ranges

Radar - Valid Monday June 21st 2021

Widespread rainfall through much of the interior, spreading into western SA this evening. Widespread showers and storms through the south with snowfalls over the Stirling Ranges and local hail and thunder reported along coastal areas in high winds. Drying out over the west coast in southerly winds.

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

Widespread rain spreading west to east over the next 5 days with moderate falls, locally heavy about some coastal and mountainous regions. Another wave of wet weather will reach the southwest later in the weekend with more heavy falls possible for the southwest land division. Some light rainfall over the tropics also possible. Another band of tropical moisture may develop at the end of the run through northwest areas.

GFS Rainfall for the next 10 days - 00z run - Valid Monday June 21st 2021

CMC Rainfall for the next 10 days - 00z run - Valid Monday June 21st 2021

Euro Rainfall for the next 10 days - 00Z run - Valid Monday June 21st 2021

Model discussion and analysis


GFS 00z run - 500mb/18000ft flow pattern - Valid Monday June 21st 2021

GFS 00z run - Surface Pressure Pattern - Valid Monday June 21st 2021


Tuesday 22nd of June 2021

Deep upper low over the southwest with wintry weather continuing, upper trough off the east coast lifting out and clearing. A strong upper high over the southeast and east with settled weather continuing and a risk of more frost overnight and into Tuesday morning.

Widespread rain moving from the northwest through to the southeast with moderate falls developing from WA into western SA. Some thunderstorms also possible. Showers along the south coast of WA with small hail contracting east by evening, with gale force winds persisting about coastal areas. Showers clearing for the east coast as a trough clears. High pressure over the southeast with frosty nights giving way to sunny days.

Wednesday 23rd of June 2021

Deep upper low sitting off the SA coast driving gales and showers to the south coast of WA and west coast of SA. Rain along a trough moving into central and eastern SA. An upper high over the east holding firm, with heights coming up over QLD and the NT leading to warm days.

Widespread rain spreading through SA, contracting into VIC and NSW through the day and western QLD at night. Showers with gales for the south coast of WA and western and central coast of SA in the wake of the rain band. Colder weather shifting east along the southern coastline. Showers mainly morning over the east coast of the NT and QLD, but dry by afternoon, though more humid over the north. Dry weather returning to the west coast with the new high moving in.

Thursday 24th of June 2021

Deep low moving towards Adelaide with gales and showers moving along the southern coastline. Upper high lifting off the east coast allowing the low and trough to move east. A new upper high developing over southwest parts of the nation, returning the region to cold nights and settled days. Humid weather persisting over the north.

Rain increasing for southern QLD through NSW and into northern VIC with a band of rain slowing down as a low pressure system cuts off from the westerly flow for a brief period. Moderate to heavy falls over the inland and windward slopes of the GDR possible in NSW and VIC. Showers with hail and thunder and strong squally west or southwest winds over SA moving into VIC later. Fine weather returns to the west with new high pressure. Morning showers over the east coast of QLD and north coast of the NT with more humidity in onshore northeast winds.

Friday 25th of June 2021

Upper low weakening and opening up into a trough over the southeast as heights lift over the southern latitudes. A new ridge moving in from the west while a strong ridge over NZ holds firm and continues to remain slow moving to the east.

Rain decreasing through QLD and northern NSW as the low to the south over VIC begins to weaken and wash out into the westerly wind regime. A high over the southwest continues to move east with settled conditions. Showers may be wintry through the southeast with residual cold air leading to a hail risk with some showers over SA and western VIC. Fine weather for the interior though humidity hanging on over the NT with morning showers offshore the northwest coast.

Saturday 26th of June 2021

Upper trough weakening further with heights coming up right throughout the nation. A flat zonal flow through the southern ocean keeping the fronts to the south, with high pressure building over the mainland taking full control of the nation's weather.

Rain over the east of QLD connected to a weakening trough lifting out from the region. Humid with a few showers in the morning offshore the NT coast. A fast zonal flow over the southern ocean keeping the fronts to the south for now but much warmer in the west with northerly winds developing. Settled for much of the nation.

Sunday 27th of June 2021

Heights racing up over the southeast as a high pressure centre builds in strength and merges with the existing ridge over NZ. A strong long wave trough off WA heralds the next wave of severe weather for the nation. Zonal flow over much of the southern ocean and a slack flow over the nation keeping skies relatively clear and dry for now with moisture being kept back over the Indian Ocean.

Large high over the nation keeping much of the nation dry and stable. Lingering rain over eastern QLD with a slow moving trough just offshore. A front approaching the west coast bringing widespread rain and strong winds later in the day. Warmer over the west coast and cold in the southeast but becoming sunny during the day. Some coastal showers are possible about SA with a weak trough moving through later.

Monday 28th of June 2021

Upper high taking up residence over the southeast. A weakness in the ridge exists over the Wide Bay. A strong wave developing over the southwest of the nation with colder weather developing as that frontal wave moves over southern and western parts of the nation. Heights coming up over the north.

Showers along the coast with onshore winds and a weak trough in the region. A high over the southeast progressing into the Tasman Sea, but remaining the dominant force with a front that rolls through WA bringing rain on Sunday diving into the south of the nation bringing late rain to the west coast of SA. Strong winds developing through the southern ocean.

Thursday 1st of July 2021

Upper low over SA and one offshore WA, with a slack pressure flow through the region. High pressure off to the southeast and southwest of the nation and heights about normal over much of northern Australia.

Unsettled with a few showers and thunderstorms with a trough over SA but limited moisture in this run. Showers along the east coast in onshore winds but light falls. Some morning showers over northern Australia with a easterly wave and light winds. A weak front passing through to the southwest of the nation but remaining dry for now. THIS WILL CHANGE!

Need more weather information for your part of the world? Email me at karllijnders@weathermatters.org

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