Radiative transfer models which have been used to compute Jupiter's millimeter wave emission do not agree well with the existing ratio astronomical observations (e.g., de Pater and Massie, 1985). This apparent discrepancy has gone large unexplained due to lack of laboratory absorption data at these wavelengths coupled with uncertainties in the calibration of millimeter wave observations. Gaseous ammonia (NH3) is the largest source of millimeter wave opacity on Jupiter. Previous laboratory measurements at 7.5- to 9.38-mm were inconclusive as to which theoretical line shape most accurately describes the millimeter absorptivity of NH3 (Jointer et al., 1989). We have made additional laboratory absorption measurements of gaseous ammonia at a shorter wavelength (3.2 mm) where the theoretical line shapes can be better evaluated. We have conducted measurements at a temperature of 210 K, at pressures ranging from 1 to 2 atm., and in a mixture consisting of 85.56% hydrogen (H2), 9.37% helium (He), and 5.07% ammonia (NH3). We give a revised formalism for computing NH3 absorption in an H2/He atmosphere using the Ben-Reuven line shape. We investigate several other potential millimeter wavelength absorbers and give revised formalisms for computing their absorption. We have compiled a list of Jupiter's reliable millimeter wavelength observations. We compare our list of observations with synthetic emission spectra utilizing our revised expressions for computing absorption. ¿ American Geophysical Union 1991