• Widespread severe weather ongoing through the southeast this afternoon and this evening with a polar airmass sweeping through.

  • Showers and storms moving into VIC and NSW tonight with low level snowfalls developing.

  • Showery weather begins to ease later Sunday over the southeast then southwest WA turns wet.

  • Fast flow pattern continues next week, meaning the northern and eastern inland will remain dry and warm to hot north of the jet stream.

  • Is there still a pattern flip on the cards?

National Satellite - Saturday 24th of July 2021.

The cold airmass has arrived and with it the severe weather profiled this week. The peak of the cold air still to come for southeastern inland areas, and that will arrive overnight. Fine and dry over the north, but note the tropical waves north of the nation and the moisture plume again off the west coast of WA. Ready for a wet week of weather out west. Dry and blustery along the east coast and through most of QLD.

The cold air has arrived with multiple rounds of squally storms and small hail with moderate rainfall for the large parts of SA today and now that is onward into western and central VIC with some moderate rainfall. But this is a cold and wind event for the most part.

State of Play National Looks.

It does not get much busier on the charts with many pieces to watch and many systems to roll through, in phase and out phase with each other. The models will waltz around with the moving pieces and be low confidence in the medium term due to the waves up north, the waves to the south and the relationship of the jet streams.

Rainfall for the coming 10 days

Rainfall is largely unchanged from this morning with more wild weather for the southeast this evening and persisting through Sunday morning. Another strong front will line up the southwest during Sunday afternoon into Monday. That may drag that moisture offshore again with areas of rain and a few thunderstorms. More periods of rain to come this week for the west with the frontal barrage to ramp up there, and then strong fronts to come through the south and the southeast Tuesday, Wednesday and Friday. The later system holds the most promise for more inland rainfall. From there, do we get a pattern flip into the first week of August or do we have to wait one more week for the westerly winds to settle? That remains to the question that is unanswered.

00Z GFS Surface Pressure Pattern for the coming 16 days

The GFS is continuing to hold firm on the westerly wind regime with the rainfall again confined to the southern parts of the nation with significant spells of windy and showery weather for the south of the nation if this verifies. Some evidence of rainfall coming inland with each frontal boundary, but with moisture hanging offshore and over northern Australia, be aware that this model will change for the medium term so I am assigning a low confidence forecast strap for the period.

00z GFS Rainfall for the coming 16 days

Rainfall is largely unchanged from this morning but there are hints of inland rainfall developing through NSW and VIC with the frontal systems and developing over inland WA with the fronts mid to late this week, keep watching that moisture offshore.

00z Euro Surface Pressure Pattern for the coming 10 days

Euro is largely unchanged from this morning, this deterministic set which people utilise readily on all the apps galore, will show that the rainfall has gone from inland areas, but the ensemble is wetter and I am siding with rainfall breaking out on frontal boundaries later next week and spreading over southern and eastern inland areas of Australia. This forecast too holds a low confidence forecast given all the mechanics in operation through the nation and offshore the north and west.

00z Euro Rainfall for the coming 10 days

Euro still has inland rainfall but not as far north as this morning, with plenty of frontal weather pushing through the nation as the westerly wind belt dominates. The moisture offshore the west will continue to be drawn into the northwest jetstream and I do think a front later next week will pick it up and move that trough the eastern inland of NSW and possibly over much of central and southern SA, and all of VIC. But the moisture has to be in phase with the frontal weather, that is be captured by the front and dragged east.

00z CMC Rainfall for the coming 10 days

The latest CMC starting to pick up on hints of that moisture over the inland, so again careful watching of the guidance from all data sets is crucial this week. Maybe storms for parts of the NT? I don't know about that, however heat levels and one of those westerly moving waves digging a little further south could kick off a shower or storm.

12z KMA Rainfall for the coming 10 days

This was from this morning and does show the moisture a little deeper and being utilised fully over inland areas.

I will have the state based forecasts on Sunday with a look for the week ahead. A 2 week forecast to be updated as well, to see whether we can get any more light about this signal from some of the models around a pattern flip in the first week to 10 days of August.

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