Volatility, as a metric for price uncertainty, is an important quantity for suitable trade strategy and risk control. This work develops a phenomenological volatility model based on a heterogeneous microstructure framework in which the market agents of speculative activity respond to information arrivals. The dynamic features of volatility, modeled as a stochastic process, is governed by asymmetries in the informational flow across different time resolutions. Among these features, we highlight the stylized facts of long memory, clustering and leverage effect. These proposals are contrasted with our empirical analysis of a ten-year time series of one-minute Brazilian market Index.