Introduction to the ACIS GridData call. GridData allows access a number of gridded datasets. Available datasets include real time and historical gridded station observations as well as climate projections from General Circulation Models (GCM) It incorporates software that allows both temporal and spatial summarization of the data. Summarization options include average, extremes, counts of days over a threshold, runs of days, and first/last occurrence of a specific condition. Data can be summarized by state, county, river basin etc. The call also includes png as an output option allowing users to map desired output.