The dry node flagging file (everdried.63) file was created to support harmonic analysis by flagging all nodes that had ever become dry during the course of a simulation. These data are useful to harmonic analysis because a node that goes dry for a single time step has a -99999 recorded for its water surface elevation, which contaminates the harmonic analysis solution.
The file contains two data sets. The first dataset provides information about the wet/dry state, where a node is given a value of -99999.0 if it ever went dry during the simulation, and a value of 1.0 if it was wet for the entire simulation. The second data set lists the total time in seconds that a node was dry during the simulation (0.0 if it was always wet).
See everdried.63 file format for details.