NSW - WET WEATHER SHIFTS NORTH MID WEEK BUT FURTHER RAINFALL POSSIBLE IN THE EAST THIS WEEKEND.

OVERVIEW

A deep trough and moisture load that brought near 900mm of rainfall to parts of the east in recent days is on the way out and a drier and more stable airmass is starting to clear the inland of the east as we see high pressure nosing in from the west.


The eastern coast should continue to see showers, but the deep low offshore could spin up a satellite feature and that may clip the Mid North or Northern Rivers Thursday or Friday.


Another trough will also move over the region with the chance of some further moderate rainfall along the southeast and eastern coastal areas.


SHORT TERM

So the persistent troughing over the east coast is forecast to bring further wet weather this weekend and into early next week but the block creating that wet weather should lift out a little bit faster than what models were predicting about 2 days ago which is good news.


That opens the door for frontal weather to approach this time next week with patchier falls returning to the Southern Inland west of the divide in more typical Winter weather.


LONG TERM

There are indications that more typical frontal weather will begin to dominate the synoptic pattern through the early part of next week with showery weather returning to SWLD of WA initially with moderate falls this weekend and then that front moving through the southeast early next week helping to knock the block out.


There is evidence that further westerly winds and showery fronts will continue to impact southern Australia through mid month and into the latter part of the month.


With some luck this will dry out the eastern and northern parts of the nation. But, there is also some modelling that keeps the moisture in place over the eastern inland of the nation which could result in an other rain band forming on a stronger trough in the medium term as well.


AREAS TO WATCH

The SAM mode over the Southern Ocean, some signals we see that tending more neutral as we go through the back half of the month and that may support more seasonal weather across the nation, with a low severe weather risk.


Watch the moisture over the Indian Ocean as well, that will come back into play during the back half of the month as well, whether that can influence moisture being fed into cold fronts remains to be seen.


WEATHER VIDEO PM - TUESDAY 5TH JULY 2022

FORECAST

Rainfall Next 10 Days

Rainfall is expected to remain widespread along the coast with the low-pressure system hanging on offshore and onshore winds continuing, some heavier falls are likely but now focussed further north along the coast with moderate falls towards the south and lighter falls to the VIC border. The inland looks to be drier once we lose this persistent cloud and drizzle under the southern flank of the upper low. Over the weekend, another trough will move through the state with a burst of rain likely once again over the southeast and coastal areas with additional moderate falls. There will be some chance of showers developing for the southeast inland this weekend, but overall falls light. Next week, there is evidence of another front moving through the southeast of the nation, there is a chance that this front lifts up the moisture left over from this easterly spell and we see another band of rain along that feature, but I won’t draw in higher rainfall totals for the inland until we know the evolution of the low pressure developing later this week and how the trough moves through over the weekend, making room for the front and trough coming out of the west next week.

The bullseye for heavier rainfall is now found north of Newcastle with heavy falls over 100mm possible about some areas of the coast Thursday with a low forming nearby.

WEATHER ISSUES

East Coast Low Bringing Heavy Rainfall to the Northern NSW Coast.

Watching the threat of this developing low offshore for the region very closely. There is a lot of very deep moisture to work with and rainfall totals may exceed 100mm quite easily along the coast and adjacent eastern facing coastal hinterland.

FURTHER EAST COAST LOW DEVELOPMENT THIS WEEKEND.

The risk has eased in recent updates which is good news with modelling placing the low-pressure potential further to the east.

MEDIUM TERM FORECAST

July 12-19th 2022

Rainfall Anomalies

Probably the biggest shift has been in the removal of that dry bias on all models this evening across the nation but no strong pull to either above and or below average rainfall across the nation highlights the uncertainty out there about the moisture returning through the jet stream and the impacts of frontal weather over the south. Seasonal weather over the north and east.

Temperature Anomalies

The cooler bias continues for large areas of the nation, especially northern Australia which will still be recovering from the cold outbreak of the past 2 weeks and more cloud and rainfall spreading through the south with cold fronts will reinforce the cooler and drier airmass over the region. Seasonal weather generally back west with cold fronts and a northwest flow.

DATA - Refer to the video for further information


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

Refer to the video for the short- and medium-term breakdown of the daily weather pattern.

00Z GFS - Precipitable Water Values - Next 2 Weeks

The moisture continues to be shunted off the coast and clears with a trough this evening. There will be onshore winds and moisture ongoing for the NSW coast where rainfall could be torrential at times with the moisture profile in place. Dry air most elsewhere through the inland supporting the widespread frost under clear skies tonight. Modest moisture through WA in the coming days ramps up this weekend with a strong cold front, that will be the first easterly moving moisture in about a fortnight to have rainfall attached to it for the southern parts of the nation. The westerly wind regime continues through the period but no great source of moisture is drawn in on this particular run but as per the video it is lurking over northwest of Australia.


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

A closer look in - the rainfall over the east is easing, we do have one more go of heavy rainfall for the northern coast of NSW which will need watching over the coming 2 days before it clears later Thursday. The south, your rainfall numbers are coming up for early next week as a system rolls through which may see a low form on that as well which may enhance rainfall. Further fronts try and get into the southeast during the medium term but confidence beyond about 5 days is atrocious.

More coming up from 8pm EST with a look at the models and rainfall.


0 views0 comments