A big flood resulting from the eruption in Grimsvotn is not expected in the near future. There was a flood from Grimsvotn in the Skafta river last year, so little water has accumulated there, and the icecap over the caldera was thin. Therefore, less ice has melted and less water has been added to the subglacial lake.
The water that accumulates will advance the next flood. If the eruption shifts to a place where the icecap is thicker it makes a flood more likely.
There were floods from the glacier shortly after the last two eruptions started in Grimsvotn, in 1998 and 2004.
