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Objective analyses on vertical cross sections are presented as examples of the type of real-time product available on the Penn State, Department of Meteorology, on-line minicom-puter. The analyses are not new, but their real-time availability is. Our experience has been that such products improve forecaster diagnosis and understanding and suggest that the "man-machine mix" concept, extended to other types of analyses and diagnoses, may be as appropriate to small machines as to large ones.

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Regression equations have been derived for albedo in the United States, summer and winter, as a function of conventional meteorological variables of the type that might be available from a . numerical model. For monthly mean patterns, the variance reduction was from 60% in summer to 84% in winter on test samples. On a day to day basis, the reduction of variance was from 45% in summer to 55% in winter. Still, errors of estimate are smaller in summer than in winter.The principal predictors were the mean relative humidity below 500 mb, and the pole-ward meridional wind component aloft. In addition, a snow-cover variable was needed in winter. Dynamic predictors, such as vorticity advection or vertical velocity, had relatively little skill and did not enter the equations consistently. Also, stability parameters played an unimportant part.