Tropical cyclone Winston is now a Category 4 storm and is probably going to make a direct hit on Fiji, tomorrow, Saturday. It will likely be a record storm for Fiji.
The storm is fueled by high sea surface temperatures, which extend to a significant depth, which probably caused the storm to intensify rapidly and to such a high state.
Jeff Masters and Bob Henson have written up the important information on this storm, here.
Fiji has been hit with a number of bad tropical storms, mainly concentrated in recent decades.
UPDATE (Friday PM Central)
Jeff Masters and Bob Henson are now reporting that Tropical Cyclone Winston is expected to grow in strength to become the strongest tropical cyclone ever recorded in the South Pacific waters east of Australia, with winds reaching 185mph.
Simon Donner of the University of British Columbia mentioned to me that the sea surface temperatures around Fiji are not so high because of the current El Nino. Normally during an El Nino this area is relatively cooler, and instead, tends to get warm during La Nina events, because of changes in the regional part of the Intertropical Convergence Zone. So, these high temperatures can pretty much be attributed to anthropogenic global warming.
Meanwhile, on his Facebook page, Simon refers to "The unusual history-defying path of Cyclone Winston. Models predict the storm may actually do a full loop." Here is what that looks like: