From this link:
The World Meteorological Organisation confirmed in a statement that a "very clear" disruptive La Nina current was underway across the equatorial Pacific Ocean, in line with its forecast in July.
It signalled that the event was associated with "climate-related risks" which needed to be assessed locally in different regions around the world.
However, this year's La Nina differed by producing cooler than normal sea temperatures off northern Australia and Indonesian islands -- the opposite of what was expected -- and was unusually combined with separate sea surface temperature shifts in the Indian Ocean.
"The drought that's going on in Australia right now is a very serious drought and it is one of the atypical situations associated with this particular La Nina event," said WMO climate specialist Leslie Malone.
"The textbooks would have said that Australia would have had a problem with more precipitation than they could handle rather than less," she told journalists, underlining that the current La Nina was "untypical"
La Nina usually combines tropical wind patterns over the Pacific basin with cooler than normal sea temperatures off the west coast of Latin America -- where the ocean is currently 1.5 degrees celsius below normal -- and warmer sea temperatures in the western Pacific.
Well, it looks like the textbooks are wrong now! I guess a little more research is actually needed. Apparently the science isn't "settled" on some basic local climatological phenomena.