EVENING UPDATE ON THE WINTRY WEATHER AHEAD FOR NSW.

Not much change once again in the latest guidance for rainfall spreading through the eastern inland of nation during the coming 4-5 days. So lets get straight to it.


00Z GFS Surface Pressure Pattern and Rainfall next 16 days - Tuesday 13th of July 2021.

Tonight's GFS largely unchanged in the rainfall distribution for this week coming, rain already underway over the inland of SA and that should increase on approach to the YP and points east. The weather wet on Wednesday through Friday with a broadly unstable west northwest flow, moisture is well above average so 3 days of moderate rainfall could lead to local minor flooding, a sign of what is to come this spring. In the medium term we now have two events on the board which is in line with my climate forecast notes today.

00Z Euro Surface Pressure Pattern and Rainfall next 10 days - Tuesday 13th of July 2021.

No real change for this week with widespread rainfall over southern Australia drifting eastwards as a long wave passes off towards the east of the nation. A high comes in after that and now we are seeing better agreement on follow up rainfall to return to southwest of the nation next week with stronger systems approaching the southeast and southern states later in the outlook, good to see that agreement increasing.

00Z GFS Precipitable Water Values Anomalies next 16 days - Tuesday 13th of July 2021.

Significant moisture continues to dominate the jet stream and thus we are seeing ranifall frequency increase this week with frontal weather being able to be infused with that deeper moisture layer bringing above average rainfall in a configuration which would deliver passing showers. So widespread inland rainfall, especially on and west of the range with the higher PW values. There are two more events out in the medium term that need watching as they could increase the flood risk if it verifies for parts of inland NSW and the southeast inland.

00Z Euro Precipitable Water Values Anomalies next 16 days - Tuesday 13th of July 2021.

Elevated PW values continue to dominate the nation with higher chance of the rainfall to be above average over the southeast and east with multiple troughs continuing to roll through. Then next week watch the rainfall event building in the coming days with the chance of follow up falls coming through WA and now looking likely to sweep more eastwards rather than the southward trend days ago.

00Z GFS Rainfall for the next 10 days - Tuesday 13th of July 2021.

Rainfall widespread from Wednesday with rain increasing during the afternoon and evening as the unstable cyclonic northwest flow descends over the eastern inland with the topography squeezing out the cloud that races up the divide, bringing enhanced pockets of rainfall. Showers continuing for the plains with the chance of thunder. Then a strong front with moderate rainfall for the southern half of NSW during Friday with heavy falls about the southeast inland with snowfalls developing. Conditions ease over the inland Saturday afternoon but as you can see, more rainfall exists in the medium term in about a week from tonight and then after that. So plenty on the board if GFS is correct.

00Z Euro Rainfall for the next 10 days - Tuesday 13th of July 2021.

Rainfall guide largely unchanged but has come into line with GFS with those heavier falls over the Northern Tablelands. These may increase further in the coming 24hrs and extend to the Central Tablelands. Looking soggy until Saturday then more rainfall potential from this time next week.

Rainfall for the next 10 days - Valid Tuesday 13th of July 2021.

I have lifted the numbers along the divide with better guidance now that real time data and observations are being fed into the modelling, the wetter signal looks good in the unstable northwest flow over the elevated terrain from Stanthorpe south to Alpine Victoria. Though on the eastern side of the range, the lee, drier conditions expected this week. I have not quite factored in all the rainfall next week as it is low confidence so this week could be very damp across those exposed to the westerly wind regime. Further rainfall coming into SA next week is being drawn in now.

Rainfall for the next 10 days - Valid Tuesday 13th of July 2021.

A closer look at those falls expected on the higher terrain and you can clearly see those areas expected to get persistent light to moderate rainfall, it will be heavy at times as troughs and fronts push through, however persistent. There is a flood watch out for the Tumut Valley for this event, spelling out how wet conditions are in this part of NSW despite it being relatively dry in recent days. More rainfall is expected next week.

Rainfall for the next 10 days - Valid Tuesday 13th of July 2021.

Also lifted rainfall numbers over northern NSW with the topography playing a huge part in lifting the moisture into rainfall as a gusty northwest to westerly flow rolls over the range. East of the divide, not much getting through with patchy falls possible. Rainfall heaviest between Wednesday night through Friday afternoon with up to 50mm possible in some locations on the divide. A flood watch has been issued for some locations.

More details to come in the morning, where I will start to issue element charts for thunderstorm risks and winter impacts. Farmers and Graziers should be advised a colder burst on Friday into the weekend will pose a risk to stock.

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