NSW - A GENERALLY FINE EASTER BUT RAIN DEVELOPS NEXT WEEK FOR THE SOUTH.

The weather is looking gorgeous over the next few days, there are showers along the coast but overall the weather is seasonal, cool nights and mild to warm and sunny days.


When we hit the weekend, the temperatures are forecast to be above the average with a northwest to northerly flow. Coastal areas should also see some lovely weather with a sunny sky and temperatures also above average.


Now as we get to Easter Monday, a front is forecast to whip through the southeast of VIC and this will carry in some moisture in the upper levels of the atmosphere, helping to promote a cloud band. There will be a cooler airmass trying to move northwards into the hot Autumn airmass and the moisture and the jet stream is the clash zone between these airmasses. That leads to widespread cloud development and possibly a rain band developing.


It should rain fairly well out of this event over Victoria but it could also clip the southern inland of NSW and the ACT with some moderate rainfall possible. The moisture will linger through next week after Easter but it is looking out of phase with frontal weather to the south.


Overall, the weather pattern is complex but we are seeing a little more agreement that the drier weather that was being forecast may not be as long lived for southern areas of the state but northern and coastal areas could remain dry through much of next week.


Lets take a look

FORECAST

Rainfall Next 10 Days

Rainfall is strictly coastal with the coverage decreasing during Thursday and by Good Friday the weather looking much more settled and drier for many areas along the coast. Inland, cold nights are forecast but sunny days to follow with no rainfall forecast at this time. The next change will approach as mentioned from Monday with the better rainfall coverage moving through Victoria at this time, but this could shift into southern areas so be aware your forecasts may change. The dry weather should continue through 10 days over the north and pockets of the coast as well, could see a dry 7 day stretch next week.

MEDIUM TERM - April 20th-27th 2022

Moisture Watch Next Week

You can track the moisture from after Easter from northwest to southeast across the south of the nation, that is advance of a trough of low pressure with a jet stream cloud band attached moving through the southern states. Higher moisture content over the northeast tropics will lead to more widespread above average rainfall coverage but the tropical airmass will begin to move east and the moisture should begin to return to seasonal values at the end of the period. Dry air along the east coast at this time.

Rainfall Anomalies

The rainfall is likely to be winding down over the northeast tropics with a return to more seasonal distribution of rainfall likely by the end of the period. Over the southwest, persistent cloud lingering with a jet stream aloft and a moisture plume from the Indian Ocean will lead to rain featuring on most days through the period, but not a strong signal for a severe weather event. The moisture and rainfall signals increase as you head through southern SA and into western VIC and NSW as we get towards ANZAC Day and thereafter with a wave of low pressure moving into the Bight and a series of fronts, possibly the first for the season, bringing rain periods. Seasonal weather elsewhere.

Temperature Anomalies

The above average temperatures will continue for the east and southeast extending back through southern and central Australia but the warm airmass will begin to be shoved east and north as we see a trough and front approach from the west leading to a cooler westerly spreading through Southern Australia by the end of the period. Over northern areas, it will be very warm and humid but seasonal temperatures overall. Some cooler bias is possible for the northeast tropics.

DATA - Refer to video for more information and the model comparison and context about all the forecast products you see from me.


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

The latest GFS is certainly going off in the second week of the outlook, but do not be fooled by that major system in the second half of the outlook. That is just expressing the changeable nature of the weather in this period, and yes there could be some more rainfall opportunities, but like the bogus cyclone off the QLD through the early part of the period, do not believe everything you see in model land over the coming days. Interesting signals none the less.

00Z GFS - Precipitable Water Anomalies - Next 2 Weeks

The moisture content is interesting, and it could easily be a more productive system emerging next week in terms of rainfall across the nation from northwest to southeast so watch this space. Discount the cyclone off QLD for now. Medium term showing much more rainfall opportunities if this moisture prognostic verifies.


00Z GFS - Rainfall Accumulation - Next 10 Days - VERY LOW CHANCE

Refer to the video for more context and analysis

00Z CMC - Rainfall Accumulation - Next 10 Days - LOW CHANCE

Splitting the difference with the Euro and GFS tonight, it sees the impact of the positive SAM phase and amplifies rainfall over the east coast. Has a weak convergence zone, not a tropical system, over the northern Cape York and another rainfall event mid next week from WA into SA. Lots to watch.

00Z Euro - Rainfall Accumulation - Next 10 Days - MODERATE CHANCE

Doesn't amplify the rainfall in the east as much with the positive SAM but what the Euro is doing is focussing more energy into the trough and rainfall potential over the south and southeast with a stalled out cloud band which could bring multiple days of rainfall through Monday to about Thursday next week if the ridge allows. As mentioned in the video, no cyclone over the northern tropics but heavy rainfall still possible this Easter.

00Z GFS - Rainfall Accumulation - Next 2 Weeks

Refer to the video for more context and analysis

A closer look in - this will likely change... I just want to make that very clear. We are seeing rainfall chances increasing for southern and eastern Australia through the coming 2 weeks, but it could be a lot more or a lot less than what is being shown here. So watch this space with the updates through the coming long weekend.

I will have more from 8am EST on Thursday and tomorrow I am travelling and it will be a holiday schedule. I can see not many people are around at the moment as well which is good so no update tonight either. Gives me a chance to take a breath. More tomorrow.



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