Integrating cloud-WSN to analyze weather data and notify SaaS user alerts during weather disasters This paper presents an enhanced architecture for integrating cloud with wireless sensor networks to analyze weather data and notify SaaS users alert during weather disasters at low cost. The occurrence of natural disasters affects lives, damages property and changes our lives completely. Existing system does not support node and network level virtualization for weather sensors. The proposed system overcomes the above limitation by deployment of WSN infrastructure for multiple weather applications using virtual sensor and overlay concept. Monitoring weather data and providing SaaS and social network disaster alerts based on decision ID3 technique and provide cloud authentication using secure shell. These factors improve and provide high quality disaster alters to users and weather analysts at low cost.