Floods are one of the most deadly weather related hazards and frequently have devastating impact economically and on the loss of human lives. For the mitigation of consequences of such events, communication plays an important role. This is an era of information abundance and communication evolution; the information to which we have access is growing exponentially, and in the ways it is received and shared is evolving. All conventional communication methods such as telephone, radio, and TV could be down during a disaster. However, with the growing use of internet, social media platforms like Facebook, Twitter and WhatsApp have emerged as an important source to disseminate warning information before the event, and also for helping the affected people during it. National and local institutions are updated for this reality and are making important enforcements in developing mobile apps and websites that contain updated and accurate information, which could also be used to send automatic alerts of live updates. For example, in UK, the FloodAlerts app and flood warning maps are used for flood warning notifications by Facebook or e-mails to registered users; and in the USA, the public access online platform called Ready keep the population informed. Timely warning information about coming floods is essential for the effectiveness of the flood warning systems and also for mitigating its impact. The methods of warning about floods have to follow different approaches in function of the level of risk that the receptors are exposed; if the risk is not immediate, flood educational activities, flood maps or awareness talks could be effective techniques of information. When it is the case of urgent flood, fast and more intrusive measures need to be realized. Nowadays, the children and youngsters have the vital importance as communication agents among all the family members and relatives, with the goal of building an educated society of their essential role related to this issue. The future of flood warning needs a heterogeneous approach of complementary tools considering the characteristics of each community. This paper provides an overview of communication systems which are being used for transmission of early warning and other information before and during the flood, also analyzes the impact of these systems on flood risk reduction.