NSW - CLOUD INCREASING OVER THE SOUTH, A SHOWER HERE AND THERE TUESDAY. DRIER FURTHER NORTH

ANALYSIS

The cold front over SA is now moving into VIC and it has become the focus of weather across the country today and will remain so through tonight and into Tuesday.


A band of patchy rainfall is leading the rainfall coverage across the nation where most elsewhere is settled tonight with a dry air mass under high pressure.


SHORT TERM

The short term is dictated by the large scale high and the weak blocking pattern that has been present in the Tasman Sea, combining to simmer down the active weather load we have seen for a few weeks now.


The frontal weather will continue to glance the south of the country through the week with the chance of further showers at times but nothing widespread or heavy.


But the interest lay behind a cold front developing from later in the coming weekend, colder air underneath this feature will move northwards and could bring some higher chances of rainfall through the southeast and eastern inland of the nation.


LONGER TERM

That clearly is the system of interest and we have been talking about that for quite some time now where we are looking at a more vigorous expression of rainfall across the nation with this feature. 


Many areas over inland QLD could see 2-3 months' worth of rain with this feature though noting it does not rain much this time of year through the interior of the nation and this includes QLD.


The rainfall may be swept out to see with a cold front moving through the southeast but it could also be swept southwards if high pressure wins out over the nation’s southeast, so the pattern remains complex and low confidence for this event.


AREAS TO WATCH

The main event to watch is the one detailed above.


There may also be some rainfall developing towards WA with another cold front moving through towards the end of the month with an influx of moisture.


Overall, the SAM is expected to return to neutral values through the end of the month and into early July, but indications are for that to snake back towards a secondary negative phase as we move into the new month seeing cold fronts lifting northwards with the westerly wind belt.


WEATHER VIDEO PM - MONDAY 20TH JUNE 2022

FORECAST

Rainfall Next 14 Days

Rainfall is expected to be confined closest to the VIC border during the coming day or so with some of that rainfall spilling over the Alpine areas and towards the ACT but not much more than 5mm is expected here. The rainfall will clear by mid week with the high pressure coming back into dominate the weather pattern for the bulk of the week. That will see most of central and northern parts of the state remain dry. A strong upper trough over the weekend into next week is forecast to bring about periods of rainfall across inland QLD and along the coast there. This may sweep southwards into northern and eastern NSW initially, lower chances for central and southern NSW and the ACT for now, but as we have seen, some modelling is getting quite expressive with rainfall totals into next week but the confidence in that is rather poor.

Rainfall Next 10 Days

The bulk of the rainfall however is likely to be over southern areas in the coming week at least and this highlights that most of the rainfall will come towards the medium term still.

Closer View in on Medium Term Rainfall

Rainfall over the northeast and north is highly variable and this will continue to evolve and so scooping in the coming 2 weeks is probably fair in trying to forecast the full impact of the potential low pressure system.

MEDIUM TERM

June 27th - July 4th, 2022

Rainfall Anomalies

Lingering above average rainfall potential remains across most of the global models for the east, the struggle point in forecasting with any great confidence is how far west does that above average smear come through QLD and into NSW. The west may see some drier weather develop through this period, but only marginally ahead of the next rainfall event due through this period. Seasonal most elsewhere.

Temperature Anomalies

Cooler bias over the southeast but not colder than what we saw earlier this month, in persistent onshore southwesterly winds. Some warmer weather likely up over northern Australia with the persistent northeasterly flow and higher humidity.

DATA - Refer to the video for further information on the short and medium term analysis.


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

Not a great deal of change from this morning, but make sure you grab the analysis from the video to get context and understand the parameters behind the data tonight as it will be a volatile week of weather interpretation!

00Z GFS - Precipitable Water Values - Next 2 Weeks

The moisture content is at relatively seasonal values across the country for when we have westerly winds, though the increased volume of PW values in the westerly wind belt may see showers become a little more extensive against what we are used to seeing at this time of year which is a sign of how things will likely play out for the remainder of Winter, with more rainfall to come via the westerly wind regime and milder conditions too. The moisture over northern Australia, clearly sticking out like a sore thumb for that rainfall potential in the early stages of next week.

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 - this forecast is low confidence away from VIC and SA where the rainfall is connected to the westerly wind regime. So, check back at 8pm for the broader data sets and analysis from me.

More coming up from 8pm EST with a look at the models and rainfall, what is happening over northern and northeast Australia!?



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