The home team have had the better of the play but are behind thanks to a Ludovic Sylvestre strike midway through the half.
Forest started the brighter of the two teams, immediately putting the away side under pressure with a series of crosses into the box.
A counter-attack allowed Blackpool to finally have an attempt on goal after nine minutes, but Nathan Delfouneso's shot cannoned back off the crossbar.
A comfortable period for the home team ensued before Blackpool took the lead. Chris Basham played the ball to Sylvestre, who opened up his body and curled the ball into the corner from outside the box.
Forest responded well but despite a couple of chances for Darius Henderson, they could not find the back of the net and remain behind at half time.