A wireless mesh network includes a group of nodes configured to predict cloud movements based on voltage time series data. A node residing in the wireless mesh network records voltage fluctuations at a site where solar power is generated. The voltage fluctuations occur when an advancing cloud reduces solar irradiance at the site, thereby reducing solar power generation. The node correlates these voltage fluctuations with other voltage fluctuations recorded by other nodes at other sites where solar power is generated. The node computes a time offset between these voltage fluctuations that corresponds to the time needed for the cloud to advance between the different sites. Based on this time offset and the locations of the various nodes, the node estimates a wind vector. The wind vector can be used to perform near-term solar forecasting by predicting when the cloud will advance to other sites and reduce solar power generation.