It has been well picked by long term models for a dry spell to take effect mid May, and that is exactly what has transpired with colder than normal weather but dry weather, thanks to a large high pressure system that has moved into southern parts of Australia over the course of the last week.

It helped to propel a strong southwest flow aloft from the southern ocean, bringing in embedded cold fronts which flung that colder air north through the eastern inland, allowing us all to say goodbye to the very warm start to May.

Flow pattern from last Saturday analysing the slow moving high through this week, this forecast from the Euro has verified well and we should continue to see stable weather for the next week. This was valid from May 15th 2021.

We are entering week 2 of the dry spell over the eastern inland with little rainfall anticipated for the region over the coming week. Coastal areas of southern VIC and northern NSW into southern QLD, will see showers from time to time over the outlook period, but not connected to anything meaningful, more related to the onshore wind regime around this large upper and surface high.

Rainfall anomalies picked the dry spell for these 2 weeks, with large anomalies recognised over inland areas. The rainfall numbers flip into June, but this was a great illustration of what we are experiencing right now as a result of persistent high pressure. Valid May 10th 2021.

There are signals for a pattern flip coming in the 7-10 day window for the east. A warmer northwest flow will develop over the region, sending temperatures back above average early next week. This is as the high begins to move out towards NZ.

It will open the door for cold fronts to move out of the southern ocean and begin to strengthen within a long wave trough anchored over WA. So while the east is warming up the west will become colder with rainfall.

High amplitude patter developing next week with large long wave trough over the west, a strong ridge in the east, but that trough out west is progressive and will bring windy and showery weather to the southern states mid to late next week.

That rain and windy weather will begin to push further east as we go through the next week with the end of May looking wet and windy for the southern states as we say goodbye to Autumn.

The rainfall trends looking better as we go through to the 7-14 day range on current guides with a good covering of shower activity for southern Australia, lighter falls the further you are away from the coast. But a signal that we are moving into the "wave train" season. With the negative SAM phase developing, the frontal weather should stand up and impact larger areas of southern Australia with some luck.

Rainfall for the next 10 days - Valid Tuesday May 18th 2021.

For now the next 7 days is bone dry, a big bag of nothing for inland areas of SA, NSW, VIC and QLD with the rainfall once again remaining coastal.

Rainfall for the next 7 days - illustrates the coastal trend for rainfall - Valid Tuesday May 18th 2021.

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