def longest_run(da, dim='time'):
    """Return the length of the longest consecutive run of True values.

        Parameters
        ----------
        arr : N-dimensional array (boolean)
          Input array
        dim : Xarray dimension (default = 'time')
          Dimension along which to calculate consecutive run

        Returns
        -------
        N-dimensional array (int)
          Length of longest run of True values along dimension
        """

    d = rle(da, dim=dim)
    rl_long = d.max(dim=dim)

    return rl_long