Ian McNeilly in Hamburg: It's been slinging it down for hours here in Hamburg.
The ring is covered with a canopy but an increase in wind could obviously result in a problem.
However, whispers at the moment are that the organisers are confident that the fight will go ahead as planned and on time.
Obviously the situation necessitates officials having to consider alternative options if the weather deteriorates further but at the moment, 'alles gut' is the phrase being used.
Surreal scenes in the city centre where there is some local festival which appears to involve the whole of Hamburg coming out on to the streets dressed in weird colourful garb to dance and get well oiled. The vast majority seem to be simply ignoring the torrential downpours and continuing to enjoy the festivities.