WEDNESDAY MORNING WEATHER - THE RAIN EVENT DEVELOPS UP NORTH, COLD AIR MOVING OVER SOUTHEAST.

Updated: Jun 29

OVERVIEW

An upper trough is beginning to move towards the southeast inland today with a weak batch of showers and cloudy skies moving through SA, VIC and into NSW. A broad upper trough over northern WA will move over the NT and into QLD in the coming days bringing widespread rainfall and heavy falls, very unusual for June/July.


Out west conditions are dry and settled and through southern parts of the nation, once we lose the showers and cloudy weather, conditions dry and stable with high pressure nearby.


SHORT TERM

The bulk of the wet weather is forecast to develop over QLD from later tonight into Thursday over the northeastern inland of the nation. An upper level low that is forecast to move into NSW through Thursday is expected to add more dynamics in the atmosphere leading to more productive rainfall from the cloud band that is in place over northern Australia,


As we move into Friday and throughout the weekend, the large band of cloud and rainfall will continue to move into the eastern inland and the southeast inland of the country with widespread falls along the coast. Heavy falls leading to flash flooding is still an issue for many locations along the coast but as mentioned throughout the week, pinning that down will likely become clearer as we move through the coming 24hrs.


Out west, through the remainder of the week and into the weekend, weather is dry and settled. The next cold front approaches the west of the nation from early next week which will start to bring about a pattern flip through next week shifting the rain out of the east and bringing the rainfall back to the west and across the south after that dry spell.


LONG TERM

Not much change in the guidance with clearer the pattern flip the main feature to watch post the large rain event over the east and southeast of the nation. Once we see a series of cold fronts coming through WA next week, this will assist in knocking out the easterly wind regime and moisture away to NZ.


Looking more traditional weather wise into the end of next week with showery weather running from west to east across the southern states, drier weather over the northern and central interior and seasonal temperatures over the northern tropics resuming at this time.


AREAS TO WATCH

The Indian Ocean is an area to watch as well as the spread of the elevated SSTs surrounding Australia. We have seen that play out in recent days with the development of the cloud band over the north of the nation, highlighting the impacts of the anomalous water temperatures. This will be a feature to watch in the months ahead.


Frontal weather increasing in strength over the south of the nation with the SAM tending more neutral and negative as we move into July.


WEATHER VIDEO AM - WEDNESDAY 29TH JUNE 2022

FORECAST

Rainfall Next 10 Days

Rainfall is expected to increase over the NT and QLD on Thursday with a deepening trough and the approach of an upper low through the southeast states, all combining to bring extensive cloud and above average rainfall accumulation. Light falls over the southeast inland with a spate of showery clumps moving north and northeast throughout SA, VIC and possibly into southern NSW. The wettest days nationally look to be Friday through Sunday, with the bulk of the heavy falls with the QLD trough forecast to be Friday into Saturday and then for coastal areas from Friday through Sunday with heavy convergence falls likely about the coast of NSW south of Newcastle and also about the Capricornia down to the Wide bay. The heavy rainfall may continue about the South Coast and could extend into East Gippsland into early Monday before clearing. The rest of the nation quiet. Rainfall looks to redevelop over the west and southwest of the country with a series of cold fronts on the approach with these offering some decent chances of rainfall returning after a dry spell.

Thunderstorm Forecast Wednesday

Thunderstorms are still possible over a broad area of northern and northeastern Australia with a broad trough and deepening moisture but the coverage within this broad zone is uncertain and will likely shift in the coming days. If a strong cold front approaches the southeast of the nation, there is the chance of thunderstorms with the boundary as that moves through.

Thunderstorm Forecast Thursday

Thunderstorms will continue on and to the east of a trough over QLD and the eastern portions of the NT but the focus will be shifting into QLD primarily through the day.

Thunderstorm Forecast Friday

There is an ongoing risk of thunderstorms under a broad rain band not severe weather is likely and the cloud cover will mitigate that risk with the storms if they form, mainly elevated.

Thunderstorm Forecast Saturday

A broad upper low and deepening moisture profile could see thunderstorms develop along the east coast and the adjacent inland but conditions clearing from the western interior of QLD. Heavy rainfall with isolated thunderstorms is possible about the coastal areas.

Thunderstorm Forecast Sunday

Thunderstorm risk forecast to contract to the coast with heavy rainfall leading to flash flooding the main issues for pockets of the QLD and NSW coastal areas.

WEATHER ISSUES

SEVERE WEATHER WATCH - QLD

A heads-up area for severe weather potential, from heavy rainfall leading to flash flooding being the main concern inland and riverine flooding in addition to the flash flood risk over the coastal areas from about the Capricornia to the NSW Border at this time!

SEVERE WEATHER WATCH - NSW

Will draw in a reference point for you all to keep watch of the forecasts. If you are in the yellow zone, make sure you check back daily and even if you are near the area drawn in but not included, the weather doesn't care about where I draw the line, still pay attention. This risk zone could be drawn further west or trimmed back further north into QLD. But for now, it would be wrong to not flag this as a risk developing for the region, really from the weekend into Monday. Flash flooding and riverine flooding the main issue and some locations on current modelling could see 300mm from the event. That will become clearer as we move through the week.

Frost Forecast Wednesday Morning should ease through next hour with no widespread risk expected for a while with unfavourable conditions for frost formation.

MEDIUM TERM

July 6th - July 13th, 2022

Rainfall Anomalies

Rainfall anomalies are starting to wind down over the eastern seaboard and more generally the rest of the nation is looking at seasonal falls for now with a return to a more typical Winter pattern with westerly winds emerging over the south of the country with fronts embedded in that flow.

Temperature Anomalies

Cooler bias continues to the west and northwest and maybe over the north with cloud lurking and this suppressing temperatures. A great indication of what will occur over the Springtime through QLD and NSW and possibly over the interior as well. For now, there is a warmer bias in NSW and southern QLD with the northwest flow developing.

CLIMATE DRIVERS - SOUTHERN ANNULAR MODE - AT THE TOP OF THE POSITIVE PEAK.

The SAM has reached to the top of the apex for this SAM phase and is now set to turn back to a neutral value for the weekend but then turn back for a secondary positive peak next week so we will see bursts of wet weather for the east and a gradual return of frontal weather in response to this forecast.

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


12Z Euro Surface Pressure Pattern and Rainfall Distribution - Next 10 Days

Refer to the video for further guidance on the short- and medium-term data outlook and how that impacts you in reality.

12z Euro Precipitable Water Anomalies - Next 10 Days

The moisture is still following the script of deepening as it moves south and southeast from the northern tropics and likely to get caught up near a trough over QLD and into an upper low over NSW with widespread above average rainfall over northern and eastern Australia with this being the drawn into an upper trough through the weekend over NSW and possibly into eastern VIC. The remainder of the nation is forecast to be under relatively dry air and high-pressure keeping things settled. But the pattern is set to flip through the week with more moisture coming in from the Indian Ocean and via the westerly wind belt so rainfall rates will return to near normal for WA and SA with some luck next week.

12z Euro Rainfall Accumulation - Next 10 days

Refer to video for more information

12z GFS Rainfall Accumulation - Next 10 days

Refer to video for more information

12z CMC Rainfall Accumulation - Next 10 days

Refer to video for more information

12z Euro Rainfall Accumulation - Next 15 days

Refer to video for more information

12z GFS Rainfall Accumulation - Next 16 days

Refer to video for more information.

More coming up today with a look at the severe weather over the east and north and a detailed look at the SSTs surrounding Australia with a focus over the Indian Ocean coming up tomorrow.