Title: Bayesian Hierarchical Models for Extreme Values Observed over Space and Time Abstract: We propose a hierarchical Bayesian approach for modeling a collection of spatially-referenced time series of extreme values. We assume that the observations follow Generalized Extreme Value(GEV) distributions whose locations and scales are spatially dependent. Indeed, the GEV response surface can also be smoothed through a transformed spatial Gaussian Process. The models are fitted using a Markov Chain Monte Carlo (MCMC) algorithm to enable inference for parameters and to provide spatio-temporal predictions. Metropolis- adjusted Langevin (MALA) algorithm is introduced to generate samples from the complex multivariate posterior distributions. Computations in large sample size spatial model will also be discussed.