SA - SHOWERS CLEAR AND DRY AND SETTLED SPELL COMMENCES AHEAD OF FRONTAL WEATHER MID NEXT WEEK.

OVERVIEW

We sit in sinking air now, the upper low that brought the mainly light rainfall to the state is into NSW and we begin the long journey under high pressure. Rainfall looks minimal for the weekend, into early next week before we see frontal weather developing over WA, trying to get across into the southern Ag Areas by mid next week.


A blocking pattern in the east will determine how strong these fronts will be and whether we see better rainfall coverage through mid week or the following weekend.


The frontal weather is stacking up over in WA and these will eventually come across, but in what state, it is determined by the blocking pattern via the easterly winds over QLD and NSW.


SHORT TERM

So not a lot of rainfall is expected over the course of the next 5-7 days, which is not uncommon for June or July, but with the warmer than normal waters over northern and northwestern Australia, it may feel like a waste of all that moisture. However it is early in the season and so sadly, patience, which crops do not have, will continue to be the only advice for now. The rainfall will come back.


Rainfall is expected to increase with frontal weather during next weekend and into the second week of July at this time, we the chance of some moderate rainfall coming through Ag Areas so it is a ways off.


LONG TERM

The east coast block is expected to move out by later next week and frontal weather which should be glancing through the southwest of the nation. That frontal weather will begin to track eastwards through the end of next week with stronger systems launching through WA then these look more likely to come across Southern Australia with more intensity as we track into the second week of July.


So once we lose the extensive rainfall over the north and east of the country, the weather is expected to return to more traditional conditions. Whether it can overcome the rainfall deficits over southern and Western Australia will be the question but right now it is unlikely.


AREAS TO WATCH

The SAM phase is important to watch over the coming week, if we see it head back into a negative phase then the frontal weather coming through in the second week of July could be very productive given the location of the wave action over the Southern Ocean.


The Indian Ocean is forecast to remain warmer than normal and this will feed moisture into the jet stream, whether it does it with the next wave of active frontal periods in the first part of July will be the issue, but most climate models support above average rainfall for July.


WEATHER VIDEO PM - THURSDAY 30TH JUNE 2022

FORECAST

Rainfall Next 10 Days

Not a whole lot, as you can see the wet weather is forecast to be further east where that rainfall and moisture will stall for a number of days. Fine and dry weather over the state and points back west through WA. This will be the pattern until about mid next week when we start to see the pattern breaking down and more mobility in the frontal weather from west to east. How strong they will be will be determined by the blocking pattern. Mainly light rainfall with the fronts for now, but we could see some heavier falls over the state by the end of the period here, but more likely into the medium term.

Not a great deal of soaking widespread rainfall forecast through the Ag Areas across the coming week though frontal weather will return, with patchy showery coverage, heaviest about coastal areas and limited falls making it inland at this time.

Placement of high pressure and the dry air, blocked through the region thanks to the major weather events over in the east is seeing the dry air stick around for another week or two. The region back towards inland WA quiet with the ridging close by so we will be relying on cold fronts to bring back wet weather. Not uncommon, just hard to stomach when there is so much rainfall falling over areas that are normally dry.

MEDIUM TERM

July 8th - July 15th, 2022

Rainfall Anomalies

Relatively seasonal conditions forecast across most of the nation, though there are some increasing signals on the modelling, some quite aggressive, for rainfall being above average over the southeast and south of the country and possibly about the southwest. I would like to see more modelling on board for the higher rainfall chances to be extended into SA and NSW but right now I am not convinced of it.

Temperature Anomalies

There has been a shift towards a cooler bias across the nation in recent days and while I am seeing that colder bias, I am not confident on it being as cold as models suggest so keeping things milder over the east and southeast, cooler over the north and northwest and across western parts of the nation.

DATA - Refer to the video for further information.


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

As mentioned, there is so much going on in this active pattern and to cut down reading time, refer to the video at the top of the page.

00Z GFS - Precipitable Water Values - Next 2 Weeks

Moisture levels remain excessive along the east coast with some very heavy rainfall totals to develop for this time of year in response to that. The deeper moisture moving out of the NT, through QLD and into NSW and then remaining along the east coast, which is representative of the positive SAM phase. Overall, the pattern will breakdown mid next week, meaning that conditions along the west coast and through southern Australia will remain dry and settled under high pressure. Moisture will overcome the drier airmass over in the west by the end of next week, that moisture then spreading along the southern coastal areas bringing up the chances of rainfall for southern Australia once again and drier air moving back over the eastern and northern parts of the nation.

00Z GFS - Rainfall Accumulation - Next 10 Days

Refer to the video for more context and analysis

00Z CMC - 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 - rainfall totals start to pick up again for SA as we move through later next week and I would be watching the moisture content coming through WA in the days ahead as there are better signs in recent runs. Once we lose the events over eastern Australia, we will get a better handle on the weather coming out of the west into July.

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

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