FRIDAY EVENING WEATHER - STRONG COLD FRONT OUT WEST AND SHOWERY SOUTHERLY WINDS EAST. DRY ELSEWHERE

OVERVIEW

Showers are continuing to lift northwards through the southeast and east of the nation tonight with a trough of low pressure working through towards the Tasman, the airmass cold over the southeast but drier, helping to ease conditions over the east and southeast of the country.


The weather over the southwest is increasingly windy with a front approaching WA tonight and tomorrow and that will form the focus of the rainy and most active weather nationally this weekend.


Over the north and northeast, the weather settled and much drier, a much more pleasant weekend of weather on the way.


SHORT TERM

So we will have one last spoke coming off that soup bowl of low pressure in the Tasman Sea working through the east of the nation this weekend with mainly light to moderate falls available along the coast. The weather clearing Sunday.


The first in a series of cold fronts are forecast to pass through the SWLD tomorrow and another on Sunday before the system consolidates through the Bight and pushes to the east with a band of showers and cloud approaching the southeast from early next week.


Stronger cold fronts will glance the SWLD of WA with those struggling to get across to the east with the lingering impacts of the low pressure in the Tasman Sea eroding the strength of the fronts to the end of next week.


Dry weather most elsewhere next week so easy forecasting for inland areas.


LONG TERM

The door may begin to swing open to more widespread rainfall developing throughout the medium term with moisture deepening from the west and northwest of the nation as a more favourable upper-level wind pattern will send moisture southwards into frontal weather and leading to bands of rain potentially laying over the nation.


The weather is expected to evolve dramatically in modelling next week with a fair few interesting wet signals developing over the interior, but do not be lured into that being the final outcome with a lot of weather impacting the nation at a more widespread level contained back to the last week of the month, there is a lot of time between now and then.



AREAS TO WATCH

How much moisture can be infused into the jet stream and westerly wind belt through the medium term, that will be the question remaining unanswered for the next week (anyone offering anymore on this topic is carrying a very degree of faith in forecasting skills).


The SAM is the climate hustler that will determine the spread of moisture via the jet stream and whether we start to see the frontal weather standing up further north and over Australia.


WEATHER VIDEO PM - FRIDAY 7TH JULY 2022

FORECAST

Rainfall Next 10 Days

A few showers are continuing over the southeast of the nation tonight and these will likely extend over parts of coastal NSW through the next 48hrs before clearing east. So, rainfall remains strictly coastal with a westerly wind regime and a series of cold fronts over the coming 10 days driving the wet weather across the nation. The rest of inland and interior Australia dry for a while under ridging and drier air as the pressure pattern adjusts to a more zonal flow, that will mean the ridge will become flat and influence a larger area as it should at this time of year. Under the ridge, that is where you find the faster westerly flow and a few waves of low pressure will bring showers, more widespread about western TAS and SWLD of WA.

SOUTHEAST AUSTRALIA

Showery weather tonight about the south of Victoria will begin to lift northeast through towards southern NSW. Could be a heavier period of rainfall about the Gippsland Coast along the 90-mile beach. The weather clears from the west during Saturday as high-pressure noses in then we see showers increasing for the NSW coast a southerly wind shift evolves as a result. More showers develop over the southeast of the nation mainly west of the divide through NSW and across much of VIC with a weakening cold front Monday into Tuesday. Then dry until the next front approaching later next week into the weekend, that offers better rainfall spread.

VICTORIA

The showery weather as mentioned above more widespread tonight then clearing. Another batch comes through on Monday and Tuesday heaviest through the southwest of the state and then better rainfall prospects look to emerge about later next week into the weekend with a stronger trio of fronts approaching from WA.

SOUTH AUSTRALIA

No rain expected inland. Light falls for the northern Ag Areas this Monday before conditions clear on Tuesday. Rainfall a little more persistent from a line south of Poochera, to Whyalla to Renmark early in the week before that too clears off Tuesday. Fine weather through mid-week but we may see a stronger front approaching with low pressure later Friday into the weekend, that offers a better chance of rainfall.

WESTERN AUSTRALIA

The rainfall is expected to be widespread and moderate during Saturday and continue east on Sunday before the front weakens and the rainfall coverage thins out under thick cloud over. The showery mess in the wake of the front will clear to the east during Sunday night and drier weather develops Monday before we see a return to fine weather until the next front Thursday which offers more moderate rainfall. A stronger front will likely whip through during next weekend.

NORTHERN AND EASTERN AUSTRALIA.

Away from the coast, a big bag of nothing with dry air, high pressure and sinking air motion resulting in relatively cloud free days over the interior, with a slow recovery from the cooler than normal temperatures through the week.

THUNDERSTORM FORECAST

Thunderstorm Forecast Saturday

A strong cold front passing through the SWLD on Saturday afternoon and evening may have a band of gusty storms attached to it with that then rolling over the inland areas during the evening. Storms may continue into Sunday along the southern WA coast as the front moves east.

Thunderstorm Forecast Sunday

Thunderstorms may develop further east on Sunday as a front moves east. Colder air behind the front may also have showers with thunder/hail associated with that about the southern coastal areas.

Thunderstorm Forecast Monday to Wednesday

Nil Thunderstorms - the air is stable and cool across the nation and with dry air over northern parts of the country coupled with an upper ridge, cloud free skies for a while.

WEATHER ISSUES

Riverine Flood Risk This Week

The flooding will continue for a while in the absence of rainfall, with the major flooding expected to take a while to ease around the Central Coast. Some flooding is possible briefly over the Mid North Coast but that should ease quite quickly and head out to sea but inland areas will be dealing with large scale peaks in flooding for a while.

WEATHER WATCH

SEVERE WEATHER - DAMAGING WINDS WITH A COLD FRONT

This system is expected to bring some fairly high risks of damaging winds and moderate to heavy rainfall through the SWLD on Saturday. Isolated thunderstorms also producing damaging winds on the prefrontal trough over the inland as well from about Three Springs through Hyden to Esperance during Saturday PM.

MEDIUM TERM FORECAST

July 15th-22nd 2022

Rainfall Anomalies

A few of the international models are suggesting rainfall will start to increase in frequency over the SWLD and western parts of WA and this in line with the approach of a more robust long wave trough passing through the region. Along the east coast there may be some showery weather lingering in weak onshore winds near a trough, but relatively seasonal most elsewhere.

Temperature Anomalies

The cooler bias starting to shift north and east as a warmer northwesterly flow starts to gather pace over in WA. This is what you want to see at this time of year if you are in need of rainfall. The airmasses clashing, moisture getting involved and the possibility of frontal weather coming into the south of the country with the potential for a negative SAM, all the conditions are there for the rainfall to return to above average values to end the month and temperatures to remain below average over interior regions.

CLIMATE DRIVERS - SAM TENDS NEUTRAL.

Starting to see the members moving the needle towards a negative phase over the course of the back half of the month, but still within neutral tolerance, however this is a shift overnight from previous guidance where earlier we were looking at weak positive signals through to the end of the month, so fingers crossed we see this strengthen through the next week. This would help bring rainfall back into southern Australia and drier weather for the central and eastern areas of the nation.

DATA - Refer to video for more information and the model comparison and context about all the forecast products you see from me.


00Z GFS - Surface Pressure Pattern and Rainfall Distribution - Next 2 Weeks

Refer to the video for further information and the model comparison.

00Z GFS - Precipitable Water Values - Next 2 Weeks

The moisture profile is starting to mix out across the country with the deep moisture leaving the east and the anomalously drier air over the west also starting to moderate as the flow becomes a lot more mobile in the days ahead. Noting the injection of moisture coming in from the Indian Ocean ahead of frontal passages, but the fronts are too far south at the moment, so as soon as we get them further north, there is a lot of moisture lurking offshore the northwest to work with. Also, moisture looks to lurk offshore the northeast and east coast (fuelling the NZ floods this week) and that could return in easterly winds ahead of troughing in the medium term. So, lots to watch.

00Z GFS - Rainfall Accumulation - Next 10 Days

Refer to the video for more context and analysis

00Z CMC - Rainfall Accumulation - Next 10 Days

Refer to the video for more context and analysis

00Z GFS - Rainfall Accumulation - Next 2 Weeks

Refer to the video for more context and analysis and the state-by-state fly around and analysis for the week ahead.

More coming up on Saturday with the next big update here in the morning but you can catch snippets on the members only facebook page! Make sure you gain access by answering two questions upon landing on the page. Click the link below. See you there!


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