NSW - SHOWERS ABOUT, BUT THE MAIN WEATHER ACTION IS EXPECTED FROM SUNDAY INTO NEXT WEEK

A mild and soupy airmass is giving way to showers about tonight with a weak trough and that unsettled weather is forecast to persist into Friday with random airmass showers and maybe some thunder, but generally lighter falls are forecast to appear for many areas who are lucky to receive rainfall.


The far west should remain dry later Thursday and Friday with a drier airmass developing.


Into the weekend, we are watching a strong cold front that is forecast to lurch northwards into the southern parts of the nation, starting in eastern WA and then pushing into SA, then into the southeast inland with a band of strong to gale force winds and with a band of cold rain and a massive airmass change forecast to pass through. Some strong signals that this could be the coldest weather of the year for many areas.


For NSW, we will see strong and gusty winds developing during Sunday with a period of gales developing over the Alpine areas and adjacent regions before rain spreads in overnight and into Monday. The chance of some heavy falls along the front are possible and squally thunderstorms may also appear with damaging winds and small hail.


Behind the rain band, widespread showers with local hail and thunder with squalls can be expected across much of the state, more widespread over the south and central areas. Snowfalls may descend to 700m over the Tablelands.


Showers and the cold weather decrease from mid next week with a weak high passing through at pace, the mobile pressure pattern is forecast to continue with a new front and possible rain band developing once again over SA and this could make it into the southeast inland later next week into the weekend.


So, looking Wintrier now on the rainfall and temperature distribution.


Let’s take a look

FORECAST

Rainfall Next 10 Days

Rainfall is expected to be a feature across the state tonight and into tomorrow with a weak trough, but light falls are forecast and nothing widespread is expected. The next major rainfall is expected to come from a strong cold front moving through the southeast as mentioned at length from later Sunday in the west and the state overnight into Monday. Some of the rain could be heavy at times with that rainfall leading to flash flooding in some locations if thunderstorms train over the same area for a period. The rainfall will then tend to scatter showers with local hail and thunder, with moderate accumulation forecast across the southeast districts on the windward slopes. The weather is forecast to ease later Tuesday with clearer conditions setting up from Wednesday. Another band of rain is possible over SA should develop from this time next week and into the weekend, that band of rainfall and cloud could be seen across the state with follow up rainfall. More rainfall is possible into the medium term, there is a larger band of moisture spreading through the jet stream from WA that could bring yet another cold burst of weather towards Queens Birthday weekend.

A closer look in and you can see we are finally drying out over the east coast with the bulk of the rainfall forecast on and west of the divide with the westerly wind belt taking over for the next week or so with fronts back on the charts, racing through with windy showery cold weather. Anywhere exposed to the westerly wind belt will see the better rainfall.

SEVERE WEATHER ISSUES

Severe Weather Watch - Damaging Winds - Sunday to Wednesday

With the system rolling into well above average temperatures with some moisture, this will allow a very tight thermal gradient developing, with supports strong to gale force northerly winds developing ahead of the feature. So, expect to see land gale warnings for parts of SA, VIC and NSW through to the ACT and across much of TAS.

Farmers and Graziers - Sunday to Wednesday

Once the front passes through, we will see a fierce cold airmass with gale force westerly winds over much of the southeast. Widespread showers, hail and thunder is forecast and snowfalls down to low levels.

Snow Forecast - Monday to Wednesday

Snowfalls are still expected to develop through this period but the airmass is marginally warmer in recent modelling, but this will continue to be updated to reflect the snowfall potential over the southeast so expect some more changes to this as we move forward.

Frost Risk - Tuesday through Friday

The airmass begins to warm from this time next week with the new high-pressure ridge moving through, but we have to be on the watch for severe frosts developing over the southeast. Certainly, looking at the coldest mornings of the year for these areas. Possibly a freeze for parts of the ACT and points south towards the VIC border (temperatures sustained below -5C)

MEDIUM TERM

June 2nd-9th 2022

Rainfall Anomalies

Not much change in the guide with generally seasonal rainfall for most areas of the nation. The main area of above average rainfall potential runs along the jet stream through the western and central interior but here, you only need 5-10mm to see well above average rainfall at this time of year. Showery weather over the southern Ag Areas could tip the balance of rainfall spread into the above average range for some parts of southern and southeast Australia but the risk is marginal.

Temperature Anomalies

Temperatures are forecast to remain below average for a fair chunk of the nation but more likely to be well below average over the Northwest of WA where persistent cloud and rainfall ongoing with troughing offshore looks to keep things cooler than normal. A fast flow pattern should be ongoing over southern Australia leading to bursts of showery weather over southern Australia and westerly winds. Some moderation of the temperatures over northern areas is expected with the southeasterly surges moving through regularly.

DATA - Refer to the video for further information and it is critical to keep check of the data sets to understand where the next major weather events are emerging from outside of this period.


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

Not much change from this morning. More information can be found on the video at the top of the page where the information is broad. Key areas to watch, the heavy rainfall over the northwest of the nation and how much of that can feed south and southeast, the cold outbreak over the southeast this weekend and into next week and whether we see some follow up falls for southern parts of the nation. Do we have a longer drier spell for the eastern seaboard well into June as well?



00Z GFS - Precipitable Water Values - Next 2 Weeks

The moisture content is coming down from where it was from previous months as temperatures come down in value too. So the overall moisture content will reflect a move to more winter like conditions across the country. As we track into the medium term, we are forecast to see more widespread moisture running through northern and northwest areas of the country leading to elevated levels of humidity at the surface, this again leading to above average rainfall chances for the arid areas and tropical areas of the country which is quite abnormal for this time of year. The moisture could perhaps begin to spread south and southeast through the country which would lead to more rainfall chances for southern and eastern areas of the nation.



00Z GFS - 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 - a chance of widespread rainfall in the short term from Sunday through to about Wednesday and then we have to wait and see what follows. Do we see moisture spreading through the jet stream into new frontal later next week with further rain areas? That remains to be a big issue for forecasting at the moment and will need careful review in the coming days. So talking about one system at a time is the best approach at the moment.

More coming up from 8pm EST with a look at the models and rainfall.


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