I have seen this phenomenon quite often and have mostly thought that it was due to technical issues with the satellite data, but I have just witnessed something else that puts paid to this.
Often I watch how the clouds are going over Australia from the Weather Satellite feed from the Bureau of Meteorology. The images are taken every hour, and the feed I look at has a loop of four images showing the movement of the clouds.
So there I was, 20 minutes ago, looking at the clouds move across Australia when suddenly every single cloud, including those to the north over Papua New Guinea and Indonesia, "jink" southward for one cycle. In other words, there I am watching clouds heading east when suddenly their trajectory heads south-east. I have seen this before, and every time this has happened, once the southward "jink" has happened, the clouds continue along their previous trajectory.
I have had two theories about this. The first is that somewhere in the atmosphere there has been such a disturbance that the entire atmosphere "moves" to compensate. The burning up of a large meteorite or comet would cause a change in the barometric pressure all over the place, but since the burning up happens in the upper atmosphere, the lower atmosphere would only be affected in a small way.
Of course this possibility is exciting, but I have always maintained that the reason is probably due to the electronics in the weather satellite. The satellite may have moved slightly in its orbit, causing the clouds to look as if they have "jinked", or maybe it was some recurrent malfunction in the data or the processing. Of course this is not terribly exciting, but it was my preferred explanation up until tonight.
As I write this, the Williamtown Radar is detecting a large cloud mass heading towards me from the west. Like the satellite, the radar images can be put into a loop to show the speed of the clouds as they head east. And so there I was watching it when, suddenly, the rainclouds made a slight but noticeable "jink" towards the southeast.
So, in other words, a completely different and separate detection device was able to verify that the cloud masses "jinked" south-eastwards. I have saved the images on my hdd just in case.
Any ideas? Dr Stephen Yeo would be helpful at this point...