Spring 2022 NH / Fall 2022 SH Discussion Thread

Wet Winter Looms As Negative IOD Pattern Emerges
( source: Weatherzone )


What is a negative Indian Ocean Dipole and how does it affect Australia?

The Indian Ocean Dipole (IOD) simply refers to an index that measures the difference in sea surface temperatures in two regions on either side of the Indian Ocean.
When the IOD is in a negative phase:
Warmer-than-average water sits on the eastern side of the equatorial Indian Ocean, near Indonesia.
Cooler-than-average water sits on the western side of the equatorial Indian Ocean, near the Horn of Africa. This sea surface temperature contrast causes more moisture-laden air to flow towards Australia.

This airborne moisture typically increases rain and cloud cover over Australia, which decreases daytime temperatures across large areas in winter and spring.


Image: Typical sea surface temperature anomalies and associated weather impacts during a negative IOD.
Negative IOD emerging
The Bureau of Meteorology will declare a negative IOD event when the IOD index is consistently lower than -0.4 for a prolonged period of time, typically at least eight weeks.
While the IOD is currently officially neutral (average conditions for Australia), the latest weekly IOD value for the week ending on May 22 was minus -0.55. This is the first value below the -0.4 threshold so far this year.


All seasonal climate models predict that negative IOD values will continue throughout winter and possibly spring, with most models suggesting that this will be a strong negative IOD event.

*A negative IOD typically causes the following weather impacts in Australia during winter and spring:

*Above average winter and spring rainfall across parts of southern Australia.

*Increased cloud cover and reduced solar output. Stronger and more frequent northwest cloudbands.

*Below average maximum temperatures across south-eastern mainland Australia during winter and spring.

*Above average minimum temperatures across much of Australia, due to cloud trapping warmth in overnight.

*Extreme cold days are more likely across southeastern Australia, while extreme cold nights are less likely.

*Above average seasonal snowfall is more likely.

An interesting winter scenario unfolding ( perhaps ) for Australia with a possible Negative IOD ( Indian Ocean Dipole ) following on from 2 consecutive La Nina years. there is plenty of conjecture out there in the AU meterological world of the implications of such an event.
i've copied some thoughts of the weather nerds ( pros and amateurs ) what it might mean.




This bloke is a conspiritard whack job geoengineering goose who is actually quite knowledgeable meteorologically, and likes to infuse his otherwise sensible precis with genuine b/s political shit.
"Good evening all, things are starting to get interesting, with enormous volumes of much warmer than normal water surrounding Northern Australia. What makes it interesting is this set up has never been seen ever in recent history. Below we can see the current SSTs, as opposed to the 2016 set up, where we had a Super El Nino event just ending.
When that happened, the strong Easterly trades push all of that warm water into the Indian Ocean, where a Negative Indian Ocean Dipole usually sets up. That is why we have only had 11 events since 1960. On this occasion, we are meant to believe that a 3rd La Nina year preceded what is going to be the biggest humanitarian disaster this country has ever faced. We have never seen a negative IOD after a La Nina, because it cannot happen, except perhaps, and only perhaps, under exceptional circumstances.
Furthermore, the Madden Julian Oscillation is currently parked in Phase 7, over water that is some 5 degrees colder than we currently see over the Maritime Continent. That makes as much sense as the election results on Saturday night. However, those controlling all of this know that most people are distracted by Tik Toks and really have no idea about what is real and what isn't.
The latest guidance is forecasting a negative IOD figure of -1.7c for the peak in September, which indicates that this is the cover story for what can only be described as making 2016 look like a drought. What we saw in Lismore is just the entree, this next 6 months will be truly horrific, and I hope everyone makes it through safely".

Some more sensible ideas fom local weather gurus...
"G'day again and now for the IOD outlook.
Well there is Good news for those waiting for the negetive IOD. The sea surface temperatures close to the Horn of Africa are below Negetive IOD thresholds currently sitting at -0.55°C (neg IOD threshold is -0.4°C), however the IOD is still in Neutral officially, as to be declared a Neg IOD event it needs to remain below -0.4°C for 8 consecutive weeks. Effects of the Negetive event are already being felt with some very decent North West cloud band events giving some very welcome rain over the Western coastal Pilbara region in WA. This theme is likely to continue in the coming months with NW Cloud Bands likely to give some further rain across the western coast and all the way to the SE coast of the eastern seaboard. Here is the recent rainfall figures around the Pilbara region lately (May to date) and may Ave in brackets:
Onslow: 219.6mm (May Ave 47.8mm)
Karratha: 82.6mm (28.5mm)
So as you can see some decent falls already. With any luck these cloud bands will reach further north and give a drink to areas around Broome and even extending further west to the Darwin region which happens under strong Neg IOD Events. Again I'll update this outlook around once a month.
DECLARATION
This outlook is based on Data available as of May 24 on the BoM website and is subject to change in future outlooks based on newer data. All information provided is a guide only".

www.skyweather.com.au/video/6306640983112?fbclid=IwAR04d9bChQPEQvN9cp4UCjRhyPD51eRP8CY8naO3PizUQJzVhh3XOxjM5LE

I just want a god damn wet winter with the odd extreme cold day, winters have mostly sucked ass for the last 10 years save a couple of Augusts.

LETS GOOOOO

I'd kill maself in the most brutal manner imaginable if I had to fly somewhere just to get some summery temps

PHWOOOOAAAAARRRRR!!!!!!!!!!!!

In our case it will be a frigid NE'ly wind with cyclonic influence so the worst weather possible in Gay basically!