NSW - WARMING UP TUESDAY AHEAD OF RAIN DEVELOPING OF SOUTHERN AREAS WEDNESDAY

A mild to warm and sunny day is on the way for Tuesday statewide as a ridge moves further east, clearing the showers and cloud off the coast as winds veer into the northwest to west.


A front moving through the southeast will bring a warm Tuesday and Wednesday to the east and southeast. This will be the warmest day of the period ahead.

A front approaching from the west is set to bring a burst of showers and storms during Wednesday afternoon over southern areas before extending through central and northern inland areas overnight into Thursday. Moisture spreading through the northeast winds today and tomorrow over the eastern third will then be picked up by the front allowing the rainfall coverage to increase mid week.


Satellite Imagery

You can see the moisture already starting to build in the easterly winds via satellite and that should begin to move west and then southwest over the coming 24hrs and surge into the front in 48hrs.

The weather clears inland areas from Thursday and Friday we are back to fine through most of the state.


By the weekend we see the weather turn showery along the east coast with another burst of onshore winds, the wettest weather expected north of Sydney at this stage. The heaviest of the showers likely staying north of the border in QLD. Some indications there may be a trough develop over the eastern inland, and if that can deepen and become slow moving along the stalled boundary, then more widespread rainfall may develop during the weekend.


Keep an eye on the trough Saturday and Sunday.

Next week, we have multiple solutions as outlined in the medium term forecast that is pinned to front of the blog page, the weather will begin to become much clearer as the data coming in also becomes clearer.


00Z GFS Surface Pressure Pattern for the coming 16 days

The pattern again largely unchanged, the most active area of weather is forecast for the west of the nation for the next 2 days. The east of the nation likely to be warmer than average with that northwest flow. The systems to watch for SA, VIC and NSW is the frontal weather coming through the westerly wind belt during mid this week. Light rainfall and showers for SA and VIC for the most part, not much creeping through the inland. The weather trending back to dry as we go through the latter part of this week. For NSW and QLD keep an eye on the weekend trough as that could see showers become more widespread not only for the coast but for inland areas. Then as you can see some major weather developing for the medium term still likely. That is thanks to multiple inland troughs and that deeper moisture profile.

00z GFS Rainfall for the coming 16 days

The wettest weather is anticipated for mid week still, across SA, VIC and southeast NSW. The weather largely over and done with during later this week. The weather turning dry by the weekend. For eastern coastal areas of NSW and QLD, that trough over the inland could increase shower activity, but those same easterly winds, will bring mild sunny weather for inland and southern/southeast areas. The moisture likely to be pumped well inland via those easterly winds thanks to a strong high over the east this weekend into early next week. We have to keep an eye on the trough coming out of WA next week which may interact with this moisture building over the nation, to produce a more widespread rainfall event, which has been shown multiple times in recent days.

00z GFS Precipitable Water Anomalies next 16 days

The PW values are expected to increase over the eastern states with a plume coming in from the west and another coming through the easterly winds today and tomorrow and drawn south into a front that you can see, lifts that into areas of rainfall. Then another surge of drier air expected to surge through the southern states, but as the modelling suggests, the frontal weather is further south this week, so the dry air stops somewhere over NSW leaving a plume of moisture stuck over the border with QLD. That moisture may deepen further during next week as the trough retrogrades west. High pressure pumping deeper moisture over the north of the nation as well. Another surge coming into WA next week as a trough moves eastwards and that may spread further east during the medium term. By around the 20th there could be a lot of moisture waiting to be lifted by the frontal weather and or troughs.

00z Euro Surface Pressure Pattern for the coming 10 days

The Euro in good agreement with the GFS tonight and other models for the coming 5 days with the frontal weather moving from west to east and linking up with moisture over the southeast while the moisture out of the west thins out over SA. The weekend, watching the upper trough and lingering moisture over the eastern inland of NSW and QLD with onshore winds feeding the trough. Then next week the Euro now starting to come into line with the other models, with showers for the east coast in onshore winds but a trough sharpening over SA and linking up with the longer fetch easterly winds over SA, VIC and NSW to produce more widespread rainfall from mid month. Humid and unsettled over the north from mid month as well.

00z Euro Rainfall for the coming 10 days

Rainfall fairly similar to this morning with the spread settled for the west with the fronts coming through over the coming 24 hours. The rainfall for the east coast also relatively unchanged from this morning with the focus shifting north of Sydney and along the QLD coast as easterly winds increase. The weather then shifts over SA and the eastern inland with that upper trough coming through this time next week with rainfall breaking out. This will continue to chop and change but the model now coming into line with the majority of the global agencies this evening.

00z Euro Precipitable Water Values next 10 days

PW values in line with GFS for the coming 5 days which is good in terms of forecasting the short term, not much shift in the guidance for the system sweeping from west to east and the moisture along the east coast. Where it gets tricky is the upper trough and moisture involvement over QLD during the weekend and whether that seeps south and west and then weather coming in from the west next week, how does that evolve with the moisture, at this time, there is deep moisture available.

Rainfall for the next 10 days

The wettest period for the state during this outlook is with the front passing through the southern and central inland during Wednesday into Thursday. The east coast will see showers develop during the weekend, mainly over the northern coast. Some chance remains of moisture spilling over the divide into the northern inland of NSW this weekend with a trough nearby possibly triggering showers. The next major rainfall opportunity for the state still exists next week as expected from the second half of August, but pinning that down is near impossible.

Tomorrow is climate update Tuesday where we look at September 2021. I will also have part 2 in the storm series this week, looking at the flood risk for the nation for the spring and summer ahead.







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