Does anyone know under what circumstances they shut the roof? The forecast is mild but wet. Is it closed for fans' comfort or only sporting considerations?
More of an awning than a proper roof, covers the spectators but not the turf. So it's for the punter's benefit only.
And I think the roof design was for the grass as much as anything else, it retracts enough to allow direct sunlight onto the pitch when the stadium isn't in use.