The number two reason on Cliff's list is "The U.S. has used inferior data assimilation", but that will be changing next week! The Ensemble Kalman Filter goes live next week: http://www.nws.noaa.gov/os/notification/tin15-43gefs.htm
It's unlikely this will cause an upset (the US is far behind), but it should at least close the gap.
The number two reason on Cliff's list is "The U.S. has used inferior data assimilation", but that will be changing next week! The Ensemble Kalman Filter goes live next week: http://www.nws.noaa.gov/os/notification/tin15-43gefs.htm
It's unlikely this will cause an upset (the US is far behind), but it should at least close the gap.