Paper Reviewed
Salimun, E., Tangang, F., Juneng, L., Zwiers, F.W. and Merryfield, W.J. 2016. Skill evaluation of the CanCM4 and its MOS for seasonal rainfall forecast in Malaysia during the early and late winter monsoon periods. International Journal of Climatology 36: 439-454.

Working with the fourth generation of the Canadian coupled ocean-atmosphere general circulation model (CanCM4), which they describe as "a multi-seasonal climate prediction system developed particularly for Canada but applicable globally," Salimun et al. (2016) evaluated its ability to forecast real-world seasonal rainfall in Malaysia, particularly during early (October, November, December) and late (December, January, February) winter monsoon periods. And what, specifically, did this effort reveal in terms of unresolved shortcomings?

The five scientists report that "the CanCM4 forecasts reproduced the annual rainfall climatology of the region" but with (1) "large biases, particularly during the winter monsoon," that (2,3) the model also "fails to forecast the observed amplitudes and distribution of rainfall," during (4,5) "both early and late winter monsoon periods," while noting that "the model's poor performance can be attributed to [6] its failure to forecast the regional circulation features associated with cold surges and [7] the Borneo vortex," both of which phenomena are acknowledged by them to "play important roles in rainfall distribution in Peninsular Malaysia and Borneo," citing Chang et al. (2005).

And so it is that the scientific effort to correctly model this particular aspect of the earth's ever-active and extremely complex climate system continues apace.

Reference
Chang, C.P., Harr, P.A. and Chen, H.J. 2005. Synoptic disturbances over the equatorial South China Sea and western Maritime Continent during boreal winter. Monthly Weather Review 133: 489-503.