The "Southern Oscillation Index" is now in negative territory, which means that El Nino conditions are developing, as evidenced by the recent prevalence of winds from the westerly quarter.

The theory is that westerly winds bring rain into the catchments of the large southern lakes. In practice, of course, it's not quite that simple, but various forecasts do suggest El Nino will persist for some time, and our impression is that futures prices moved lower when the westerlies appeared to confirm the theory.