Showers overnight and during Monday have morning have produced a couple of decent falls over MNC and Hunter. 40mm inland of Coffs Habour the best of it. Welcome rainfall for these areas that have been dry for a while and another signal that things have shifted away from the westerly dominance.

Rainfall for the previous 22hrs to 7am

Lets look further ahead this week.

A high pressure system will move into the Pacific Ocean on Tuesday sending the region into a warm to hot northwest flow, that will bring in above average temperatures for wide areas of the state and bring a brief break from the onshore winds and showers to the east coast.

As we track through mid week, a moisture plume will be propelled west of the divide through QLD and into NSW with a front expected to capture that bringing a band of showers and thunderstorms later Wednesday into Thursday.

Temperatures ahead of the system look to be well above average, and with the soil moisture very high, this will start to see growth start to spout. The weather behind the front is not brutally cold and with more sunshine this weekend that could see the growth slowly increase over the coming 7 days.

A cooler weather is expected to sweep throughout the state during Thursday before another southeast to easterly surge for the coast bringing showers back to the NSW coast this weekend.

The medium term still full of fun and games, it is tricky forecasting but there is something still stirring on the horizon on the GFS and the Euro still the cheese that stands alone.

12Z GFS Surface Pressure Pattern for the coming 16 days

The pressure pattern is unchanged still from last night which is good for consistent forecasting this week. Rainfall numbers have come up over the southwest this morning with a front passing through, that front will spread over the southern coastline this week with the front losing it's moisture so light falls for SA, but as it comes through VIC and NSW, the moisture is deeper thanks to easterly winds and showers likely to increase. A thunderstorm or two also likely ahead of that system. Now the temperatures this week are what you expect in early spring, with mild to warm weather over the eastern inland ahead of that front. Behind the front, the weather is not as cold, with the colder air staying further south. That will mean temperatures staying seasonal to above seasonal through the coming week into the weekend. The medium term showing that upper trough over the eastern inland with a few showers and thunderstorms. Showers return to the east coast. And you can track that large scale system over the west coast coming through SA into the southeast during the middle stages of the month. Moisture also deep across the eastern and northern inland of the nation.

12z GFS Rainfall for the coming 16 days

The most productive rainfall for the period is clearly the mid week feature that lifts moisture through the east and brings a band of rain. Some of that rainfall could be heavy IF GFS is correct. Lighter falls west of the divide and over the northern tablelands. The weather dries out inland with showers developing the weekend for the coast. The weather may turn thundery over the inland with an upper trough wafting around. The medium term showing that more vigorous weather coming in from the west and north of the nation. But this will continue to chop and change. More on the medium term later this morning.

12z GFS Precipitable Water Anomalies next 16 days

This continues to show the moisture rotating around a high pressure system and being drawn south and west through the eastern inland ahead of a front. That front continues to show modest moisture along it's axis, though it is a narrow area of elevated PW values so the rainfall patchy on the front over SA this week. When the front comes into VIC and NSW, the rainfall will likely become more widespread. Over the north and east of the nation, the moisture continues to build as easterly winds dominate for the period. This will lead to elevated rainfall chances for inland areas of the east and north in the medium term but again there won't be much clarity until later this week. Most modelling in the past 24 hours have had large rainfall events all over the board, but the one element that has not changed on the GFS has been the widespread moisture available in the mid to late month period.

12z Euro Surface Pressure Pattern for the coming 10 days

The Euro in good agreement with the cold front passing through the southern and eastern parts of the nation mid week being the main focus of the rainfall this period. The weather is expected to be dominated for the most part by high pressure for the coming 10 days. Now the Euro, is still out on it's own suggesting high pressure keeping the nation dry but the larger data set from the same model shows a wetter period coming up in the medium term. So will just have to be patient this week to see how the weather evolves in the coming few weeks as it is becoming more spring like earlier this year which the modelling absolutely cannot cope with.

12z Euro Rainfall for the coming 10 days

Most productive rainfall is expected mid week along that front passing through from SA through VIC into NSW. The weather clearing later this week over the inland, the showers will then return to the east coast with onshore easterly winds. But the better coverage of showers is expected through the northern coast into QLD if the Euro is correct. The weather then turns quiet for the remainder of the outlook if this is correct.

12z Euro Precipitable Water Values next 10 days

Still suggesting that the heavy moisture signal that was being modelled during mid month is now expected to stay up over the tropics and dry air overruns the nation with high pressure dominating. I am not so sure on that. I am still siding with the moisture being the dominant feature mid to late month, regardless if there is no low pressure system lifting the moisture, I still expect it to be there more than dry air dominating. Models are bias to a moist and unstable nation mid to late month.

Rainfall for the next 10 days

Rainfall along the east coast has eased this morning with the flow shifting into the northwest clearing the southern and central coastal areas. The weather mild to warm and dry until Wednesday when the most productive rainfall event moves through into Thursday. The weather dries out over the inland Friday into the weekend at this stage. Showers return to the east coast, some of those may creep over the northern inland of NSW with an upper trough lurking so that needs watching as it could emerge as an unsettled weekend as we get closer to the weekend, these systems can pop up within a day from the event kicking off. Otherwise typical late winter/early spring weather.

More weather to come today, another moisture watch post for the medium term and will talk a lot more about the moisture and what the hell is going on for the second half of August, will it be warmer and wetter or cooler and drier? The model madness continues.

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