NATIONAL WEATHER PICTURE - AM EDITION - MONDAY 28TH OF JUNE 2021

Headlines


  • Quiet day across most of Australia with high pressure dominating the synoptic scale.

  • Showery through WA mainly later today with another front.

  • Showers developing along the east coast with onshore winds returning around a large high.

  • Low confidence forecast for later this week with a positive SAM phase creating model madness.

High pressure has continued to move in overnight bringing cold clear conditions to a large portion of the nation. This has set the scene for a large fog event through inland VIC and NSW with low level moisture trapped over large sections of inland Australia. A gorgeous day to follow if we can lose the fog.


Showery weather is expected to redevelop from the southwest and west of WA, with another front to roll through the region. Strong winds likely to develop in advance of the front moving in from the west. Colder air to follow the front tonight with local hail and thunder for the southwest coastal communities.


Onshore winds expected to bring showers from Cape York down to about Sydney with light showers for much of NSW trending moderate as you head through the Northern Rivers and along pockets of the QLD coast exposed to the southeast to easterly flow.


The forecast confidence falls away for much of the south and east with the positive SAM phase causing some issues with placements of the trough and the timing for a front moving in from the southwest of Australia into the southeast. Many questions remain on those elements for now.


National Weather Picture - Valid Monday 28th of June 2021

Quiet weather picture for Monday morning with relatively clear skies over a good portion of the nation. Cloud is drifting through inland WA but rain free. Cloud lingering about parts of the QLD coast but essentially dry. The only region where the showers and cloud are thickest is southwest WA in onshore winds. Otherwise thick areas of fog have developed over southeast inland areas this morning. This is the quietest the weather has been nationally in about 6 weeks.

Temperatures - Valid Monday 28th of June 2021 - 7am EST.

Cold start as advertised through the southeast and east with light winds under high pressure. Temperatures returned to seasonal over northern Australia, though still very warm over parts of Cape York where humidity values are still elevated. Warmer through the outback of WA and along coastal WA where the cloud has been overnight otherwise its a chilly to start the day with pockets of thick fog or light frost over the south, central and eastern inland.

Some of the coldest mornings in about 10 days for the eastern inland, but nothing too brutal. Frost has formed where fog hasn't and vice versa. The fog will take a while to clear in some locations across the southeast, so it will a while for some locations to warm up today. SA will see much more sunshine being on offshore wind side of the high.

Radar - Valid Monday 28th of June 2021

The wettest part of the nation is the southwest of WA where light showers are ongoing today ahead of a stronger cold front this evening. Otherwise most elsewhere, dry and seasonal this morning.

WA Rainfall - 22hrs to 5am WST.

Reasonable totals, with 20-30mm in pockets of SWLD, especially along the west and south coast. The showers are easing this morning before they return with yet another front over the coming 24 hours. Similar rainfall can be expected throughout the region, with only light falls coming into the inland regions.

Rainfall for the next 10 days - Valid Monday 28th of June 2021

Widespread showers expected to develop for southwest WA with another front tonight. That front will then move east through the southern coast of WA on Tuesday with colder air. A trough in the east will combine with onshore winds (the onshore winds bringing showers to the east coast) to produce inland rainfall from Thursday and persist into the weekend. Some moderate to heavy falls are possible. A front will roll through the southeast during Thursday and Friday helping to deepen the trough over the eastern inland. Dry elsewhere.

GFS Rainfall for the next 10 days - Valid 12z Monday 28th of June 2021

GFS suggesting quite widespread rainfall for QLD through the latter part of this week with scattered falls through NSW, though the rainfall distribution changing run to run, however it is consistent in pinging rainfall for QLD and northern NSW now. Showers over the southwest today, and some of that will impact the southern and southeastern coastal areas. Dry through large parts of the central interior.

CMC Rainfall for the next 10 days - Valid 12z Monday 28th of June 2021

This model is not as put together with all the elements and I am thinking this will play catch up with the other models. Showers widespread through WA and rain breaking out through QLD and NSW later this week and showers increasing for southern and southeast coastal areas. Dry for the remainder.

Euro Rainfall for the next 10 days - Valid 12z Monday 28th of June 2021

Euro still wants to bring showers through the southwest of the nation today with moderate falls. Then a trough deepens over the eastern inland with onshore winds feeding the trough to produce showers along the coast of QLD and NSW and then areas of moderate rainfall through inland areas. A low forms offshore VIC and keeps the rainfall slow moving over the eastern states through the weekend and rain and showers more widespread through VIC. Dry elsewhere away from the coast.

KMA Rainfall for the next 10 days - Valid 12z Monday 28th of June 2021

Very similar spread to Euro with rainfall over the eastern inland of the nation and showery weather through the southwest, but remaining dry as per other models through the central interior with persistent high pressure.


Model Analysis and Discussion


GFS 500mb/18000ft flow pattern - Valid 12z Monday 28th of June 2021.

GFS Surface Pressure Pattern - Valid 12z Monday 28th of June 2021


Monday 28th of June 2021

Upper high strengthening over the southeast controlling much of the nations weather, foggy starts for large areas. Long wave trough through the southwest of the nation bringing more windy and wintry weather. Zonal flow over much of the interior with an upper high over the NT and Cape York. Typical winter pattern.

High pressure through the southeast producing fog and cold starts for much of the inland of Australia this morning. Showers may develop later about the NSW coast with a southeast flow returning. Dry skies for much of the nation with northeast to northerly winds. Cloudy back through southwest Australia with showers increasing ahead of another frontal boundary.

Tuesday 29th of June 2021

Upper high over the southeast slow moving and the dominant force for much of the nation, extending to another upper high over northern Australia. A long wave passing into the Bight now encountering the upper high over the east and being dragged south.

A trough through the eastern inland developing and onshore northeast to easterly winds bringing showers to the east coast. The trough will respond to the moisture streaming in from the east with scattered showers developing later in the day or at night with a possible storm. High pressure over the west settling conditions down with clearing skies over the south and west coasts. A weak front over the Bight moving eastwards. Fine throughout many locations on Tuesday away from the east coast.

Wednesday 30th of June 2021

Trough deepening over western QLD and a long wave over the Bight will be the focus of the wet and wintry weather developing over Australia. Otherwise upper high over the southeast will continue to ridge back over the southeast and a new ridge over the southwest will keep conditions cool but settled. The heights over northern Australia coming down which could lead to higher humidity values developing with a slack pressure pattern.

Showers increasing over the eastern inland with possible thunderstorms. Showers along the east coast with onshore winds. A few showers clearing the southeast early but may redevelop once again with a strong front approaching SA with colder air to follow through the southeast at night. A few showers developing for the south coast of WA with high pressure directing onshore winds. Fine elsewhere with the ridge holding firm. Fine and more humid over the north of the nation.

Thursday 1st of July 2021

Strong upper trough moving through Bight towards southeast Australia bringing wintry weather and colder air through the region, with a broad trough rotating through the eastern inland. Strong upper high over the southeast remains slow moving and another ridge out west, not as strong, keeping the western interior dry for now. The heights over the NT come down allowing for cooler weather over the interior and more humidity over the north.

Rain and a few storms over eastern QLD and NSW with a trough hanging up as a low forms southwest of VIC, bringing cold and showery weather through the southeast. Local hail and thunder possible about coastal SA and southwest VIC later. Snowfalls also developing for Alpine areas. Fine back through much of the west. A pattern flip with the strong high developing over the west of the nation by the end of the week.

Friday 2nd of July 2021

Deep upper low slow to move through the southeast with a cold airmass spreading over the eastern and southern inland. A broad trough moving slowly through QLD and NSW with wet weather. Fine weather back over WA with a ridge moving in and settling over the nation's west. Heights still lowering over the NT.

Widespread rain and a few storms over the eastern inland slow to advance towards the coast. Some heavy falls are possible. Showers over the southeast continuing with local hail and thunder and a gusty southwest to westerly flow. Fine weather elsewhere with a flat ridge moving in from the west and keeping conditions dry and stable for much of the inland away from the east.

Saturday 3rd of July 2021

Upper low over the southeast beginning to slowly move east with a strong upper high over the Tasman, hanging up the movement of systems towards the east, blocking the flow. A weak ridge over WA being squeezed out by troughing to the east and southwest with the next front.

Rain continuing through QLD with a few storms as a trough deepens over the east. A low over southwest VIC, beginning to turn south and approach TAS with moderate showers for coastal areas, but not much rainfall advancing inland, with just a cold airmass to work with. Fine elsewhere though cool. A new front approaching southwest WA will bring cloudy skies and showers developing later in the day. Fine weather over the north.

Sunday 4th of July 2021

Upper high over the Tasman remaining slow moving . Upper trough over QLD also slow moving and bringing more unsettled weather. Upper high over the interior of SA extending to a ridge over the Southern Ocean. A wavy flow through the jet stream bringing more unsettled to pockets of southern Australia.

Rain and storms continuing for eastern QLD and extending into northeast NSW with a slow moving trough advancing eastwards. A large high building over SA extending a centre into VIC clearing conditions through the southeast with cold nights and sunny days returning. A front weakening over WA but still bringing showers. Dry weather returning to the north with a southeasterly flow developing.

Wednesday 7th of July 2021

A wavy flow continues over the nation with a few upper trough over parts WA and another leaving the east coast. Weak upper high over QLD. Strong upper ridge over the Southern Ocean but as always this is a low confidence forecast as we are 10 days out. And we are seeing the only consistency in that there will be more unsettled weather drifting through southern Australia.

Broad troughing over the southern parts of the nation with pockets of showers about, but it is a messy synoptic and suspect that this will continue to evolve with more organised weather features moving through the nation based upon the ensemble data sets this morning.

Let's check this model analysis against Euro this morning to see where we stand


Friday 2nd of July 2021

Similar to GFS, a trough moving through QLD and a strong upper trough moving through the southeast, running into better moisture over QLD and NSW, will see rainfall break out over the eastern inland.

Saturday 3rd of July 2021

Troughs deepening over QLD and NSW continuing the rain and storm focus over QLD and NSW with a deep low potentially bringing heavy rainfall through southeast VIC though this will likely continue to evolve in the coming days, this is low confidence and suspect will move around in the coming runs.

Sunday 4th of July 2021

Deep upper low offshore the south coast with a strong trough moving through the eastern inland with widespread rain and a few storms through the eastern inland. Upper high over the west clearing skies.


Need more weather information - email me at karllijnders@weathermatters.org for tailored forecasts, you may want a tailored 14 day rainfall outlook for your region or wind forecasts. Let me know.



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