Measurements of daytime temperature near the mesopause are accomplished using an upgraded Potassium (K) lidar at the Arecibo Observatory. The diurnal mean temperature structure at and just below the mesopause is determined by full twenty-four measurements, and the dominant tidal modes present at Arecibo are also determined. Gravity wave spectra in mesospheric metal layers are determined in the three variables of temperature, wind, and density. These parameters are extracted from simultaneous ISR measurements of winds and ISR spectral shape, while the K-lidar provides measurements of temperature and the resonant K emission strength. The chemistry of metallic layers in the mesosphere is investigated in the context of the full diurnal layering morphology.