NSW - RAIN EASING OVER THE SOUTHEAST - WARMER WEATHER NEXT WEEK AHEAD OF STORMY CHANGE IN A WEEK.

The weather is changeable, becoming more spring like as we go through the coming week, with the spring roller coaster ride in temps developing, going from the below average values we have experienced this week, to going well above average temperatures we are likely to see next week.


Today, there has been steady rainfall over the southeast with a trough hanging up over the region, thanks to the departing low and the cold pool over the southeast inland. There have been a few moderate falls once again over the southeast with a cold cloudy day. Further north and west it has been drier and clearer with the ridge starting to nose in.

10-20mm of rainfall has been observed around Moruya and out towards the eastern side of Captains Flat south of Canberra this afternoon.

The weekend, we are expecting a drier Saturday after showers clear the southeast. A warmer northwest flow through the west of the state, starting to spread through the remainder as a trough approaches. We have got the risk of frost however for inland areas, despite the warming weather in the coming week, frosts may still be a feature for a number of weeks between systems.

A trough moves through bringing scattered showers and a few storms, mainly to the southeast of NSW and through most of VIC as the system hits a little more moisture left over from this current event.

Temperatures are set to rise dramatically next week with many areas over the southeast inland into the high 20s and low 30s as a long fetch northwest flow develops and spreads the warmth across the nation


Warming up from mid to late next week

But here comes the change on Friday, I full expect the change to be oriented along a low pressure system rather than a front but this is where we are right at this moment. Some areas up to 12-15C above normal later next week in western NSW and VIC.

Moisture being driven out of the northeast of the nation will be filtering southwest through QLD into the heartland and then be collected by a front to trigger a large band of cloud with areas of rain developing. That will spread east in about a week's time.

00Z GFS Surface Pressure Pattern for the coming 16 days

The pressure pattern shows the low-pressure system off the southeast coast of NSW bringing widespread showers to the east coast of Victoria and southern NSW which is in the process of leaving the region overnight into Saturday. The weather over the nation is being controlled by high pressure and that remains to be the case into next week with a warmer northwest flow developing as the high consolidates over NSW, this leading to a very warm spell of early Spring weather. Coastal areas of QLD is the area to watch with welcome showers and storms forming along a pressure trough that is aligned through the central and northern inland with moisture streaming in from the easterly winds, that coverage could become a little heavier for the coastal areas between Proserpine and Mackay. The weather should turn more humid through the eastern inland next week, the moisture spreading through to central and southern parts of the nation ahead of a strong cold front. That front is expected to send temperatures way above the average over the eastern states. The systems strength and timing of the system will continue to chop and change as we wait for the system to initiate in real time and until such time I can only give you a guide. Once the upper air data is real time data, then modelling will improve. At this time rain will progress through WA from mid next week, SA this time next week through Friday and then onwards to the eastern states from Friday into the weekend with moderate to heavy falls possible if it all comes together. The tropics will turn humid as the wind profile tends north-easterly over the region.

00z GFS Rainfall for the coming 16 days

The major rainfall expected for the nation is that large scale event coming through next week from WA, through SA and into the southeast areas. Some heavy falls are possible in the southeast with this feature but again I can be more specific next week as better data is fed into modelling. In the meantime, the weather improves over much of the inland with above average temperatures returning and clearer skies. A weak trough over the south and southeast this weekend may bring showers, but that system may also help to pull a trough down through QLD and produce showers and storms for eastern inland parts and along the coast with patchy falls. Onshore winds could bring a few showers from time to time over the southwest with light falls expected.

00z GFS Precipitable Water Anomalies next 16 days

Modelling continues to support drier air over the nation being overrun through northeast part of the nation with trade winds and with another impulse over the southwest of the nation. This will start to erode the dominance of the drier air under high pressure as I continue to mention daily, we will have widespread moisture passing through from the easterly winds and then being pumped into the eastern and central inland of the nation. The trough over eastern inland QLD will bring showers and storms as the moisture is lifted through the region. One of the signals that the seasonal shift is underway. A strong cold front and trough then runs into this moisture – how that looks will continue to chop and change throughout the coming days. Through the medium term we will be watching the north of the nation where moisture increases and whether the Indian Ocean will decide to wake up and play a part in introducing rainfall through the north and west of the nation. The longer term modelling today has shifted to show a very wet 4-6 weeks coming.

00z Euro Surface Pressure Pattern for the coming 10 days

The surface pattern pretty similar in the short term, over QLD, the model divergence continues through the early part of next week, Euro sees the storms over the northern parts of the state but the GFS has much more widespread precipitation. The next frontal system over WA that brings the widespread rainfall event from west to east, is anticipated to bring a very warm start to spring over the east and central areas of the nation, but for the west, much colder start to the month that usual, that trend continues for the nation. Over the north the tropics also becoming more humid with a northeast flow. Again the modelling is supporting a more active few weeks on the way beyond this period.

00z Euro Rainfall for the coming 10 days

Euro brings in a weak trough over QLD with scattered showers for the coast, more isolated inland with the chance of thunderstorms. The main weather to watch will be out west with the large scale wave of low pressure and frontal weather passing through from the west, which will headline rainfall chances for the nation next week, as it crashes into the moisture surging in from the easterly winds on top of the strong high. The system could be interrupted by the Tasman Sea blocking pattern as well so will have to see how that impacts its progress and development. But otherwise the weather becoming warm to hot with increasing rainfall chances for the east next week.

00z Euro Precipitable Water Values next 10 days

Largely no change in moisture spreading throughout the nation, a series of troughs out over the west tries to bring in modest moisture through the southern and eastern inland of the nation this weekend but the drier air looks to win out there. Next week, once a high has re-established itself over the east, a stronger longer fetch easterly wind will propel the moisture inland to the NT and SA and this is swept up by a strong front which you can see leads to widespread rainfall developing across the nation and the moisture may build up further over northern Australia as the northeast flow continues over the north. In the longer term I am expecting more moisture to dominate the charts as we go through September. That is a gut feel, no scientific basis for that, however I have been watching weather for 25 years and these seasons can shift very quickly!

Rainfall for the next 10 days

Rain and drizzle easing over the southeast tonight and tomorrow the weather improves statewide with heights coming up and a northwest flow with drier air passing through. There will be another trough that rolls through the south during Sunday bringing a few showers and storms. Then dry and much warmer for much of next week with some areas going above 30s. The next major change is due in from as early as this time next week and that offers state wide rainfall, but do not get caught up on the distribution yet, the rainfall forecasts will be much clearer as we get into next week.

It is the weekend and I will be having a rest tomorrow to recharge the batteries for Sunday - but again I will have my short and medium term update tomorrow afternoon to keep you in the loop!


And happy 2 months to us all today!!




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