The study examined if the flood risk messages in broadcast media in select states in Southeast and South-south Nigeria effectively amplified risk perception that influenced community response during the 2022 flood in Southern Nigeria. Consistent with the assumptions of the social amplification and attenuation of risk framework, this study looked at the frequency of the flood risk communications, gauged whether the flood risk messages were considered credible and trusted by the communities, and ascertained the extent to which the messages increased public worries and provoked a sense of threat and response to the flood hazards. The data were gathered from 380 flood victims in 4 communities in Anambra (Southeast) and Delta (South-south) States using a descriptive survey method. The study found that the broadcast media information and warnings were credible and increased public concerns but the amplification of flood risk perception in the broadcast media were not effectual as the risk communication did not start in time and the impact of the messages was moderated by institutional, social, economic and psychological variables that affected how the communities perceived, managed and responded to the flood risk messages. The study recommended that the flood risk messages should be timely, emphasise the severity of the threat of an impending flood, and sufficiently dramatize the message and the threat..