The diurnal, latitude, solar flux, and geomagnetic activity variations in thermospheric NO density measured at latitudes as high as 70¿ have been parameterized with a simple, empirical model. Consistent trends are found in both rocket and satellite measurements, although there are some differences that suggest the presence of systematic errors that add factor of 2 uncertainties to the model predictions. While NO measurements taken with IR emission and &ggr; band fluorescence techniques are in reasonable agreement, evidence suggests that the ion composition and continuum chemiluminescence methods may be less accurate. The current model provides a convenient means for estimating daytime and nighttime NO densities for use in atmospheric chemistry and radiation studies. ¿ American Geophysical Union 1993